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Conservation and Biological Senescence in Polar Bears: Telomeres and Inuit Traditional Knowledge
by
Pamela B.Y. Wong
A thesis submitted in conformity with the requirements for the degree of Doctor of Philosophy
Ecology and Evolutionary Biology University of Toronto
© Copyright by Pamela B.Y. Wong 2017
ii
Conservation and Biological Senescence in Polar Bears:
Telomeres and Inuit Traditional Knowledge
Pamela B.Y. Wong
Doctor of Philosophy
Ecology and Evolutionary Biology University of Toronto
2017
Abstract Although noninvasive genetic surveys play an increasing role in monitoring polar bear
population dynamics, genetic methods of identifying age await development. Telomeres–
–repetitive DNA sequences at chromosome ends––may indicate biological senescence
and chronological aging. In some taxa, telomere length has been shown to decline with
chronological age, but may vary with tissue, sex, and environmental variation and even
within and among individuals of the same age. This thesis evaluates patterns of variation
in telomeres as a function of chronological age by i) developing a telomere restriction
fragment (TRF) assay in grizzly bears to examine how telomere length varies with age
sex, and stress in this taxa and ii) using a quantitative polymerase chain reaction (qPCR)
to determine how telomere length varies with tissue, age, sex, and population in harvested
polar bears. I also examine iii) Inuit methods of identifying polar bear characteristics to
enrich interpretations of these patterns and iv) Inuit perspectives of research and
management for insight into long-term community-level monitoring. TRF assays in
grizzly bears are able to detect age and sex effects on telomere length, yet these findings
are inconclusive. Future work using a larger sample can confirm these relationships. For
heart, muscle, and skin salvaged from polar bears, significant differences in telomere
length occur among populations and these involve differences in age and sex in muscle
and potentially skin. Telomeres will likely serve as a better indicator of biological versus
chronological aging. Inuit across Nunavut continue to share methods in identifying sex,
age, body size and health of encountered polar bears and their knowledge could inform
iii
polar bear surveys. Unfortunately, not all Inuit support current research and management
practices, suggesting there is a need to improve collaborative relationships. Including
Inuit in monitoring programs can highlight unique, novel methods of monitoring a high
profile at-risk species.
iv
Acknowledgments
This thesis would not have been possible without the support of my supervisors,
collaborators, friends, and family. This work was funded by the International Bear
Association Research and Conservation, Royal Ontario Museum Schad Conservation,
and Northern Scientific Training Program grants.
First and foremost, I would like to thank my supervisors, Dr. Robert Murphy and Dr.
Deborah McGregor for their immense encouragement and support for this work. Dr. Don
Jackson provided valuable insight and guidance in completing this work. I would like to
thank Dr. Peter van Coeverden de Groot for his innovative ideas and enthusiasm that
helped shaped this project, and the years of often-challenging camping trips on the arctic
tundra that inspired me on this path. I would also like to thank Markus Dyck for his
incredible advice and support both in the field and in my research endeavours in the
north.
This research would not have been possible without samples and biological data provided
by my collaborators: Dr. Marc Cattet and Gordon Stenhouse from the fRI Research
Grizzly Bear Program; Markus Dyck from the Department of Environment, Government
of Nunavut; and Toronto Metro, Albuquerque Biopark, Cleveland Metroparks,
Brookfield, Buffalo, North Carolina, SeaWorld (San Diego), and San Diego zoos. I
would also like to thank the University of Guelph Agriculture and Food Laboratory for
processing samples for this work. I would additionally like to thank Dr. Marc Cattet for
his advice on analyses for this work. I would also like to thank Natalie Erdmann for her
tremendous patience, guidance, and expertise in helping me establish my laboratory
experience. I would also like to thank Kathy Shire, Guido Stadler, Amy Lathrop, Kristen
Choffe, Lori Frappier, Jennifer Mitchell, Hitoshi Okada, Woodring Wright, John
Stinchcombe, Ina Anreiter, Brandon Campitelli, Lisa Martin, and Shu Chen for their
expertise, insight and support in developing laboratory procedures.
I would also like to thank Ikajutit (Arctic Bay), Arviat, Mayukalik (Kimmirut), and Gjoa
Haven Hunters and Trappers for their insight, experience, and recommendations that
v
developed this project, without which this work would not have been possible. I would
also like to offer a tremendous thanks to all interview participants and George Aklah,
Susie Issuqangituq, Kolola Pitsiulak, Akeego Akkidluak, Angie Akammak, Rosie
Ivunirjuk, Leah Muckpah, Rosie Porter, Hilda Panigoniak, Teddy Carter, and Louie
Kamookak. I would also like to thank Mosha Kotierk, Sheila Oolayu, and Jamal Shirley
for their helpful advice and experience.
To my Mom, Dad, Madelene, and Isaac, thank you so much for your tremendous love
and encouragement, for believing in everything that I do. I am so grateful to have a
supportive family. Thanks to my sisters and brothers who have supported me, who never
failed to remind me of the value and importance in following my dharma.
Finally, my heart is overwhelmed with the wisdom, generosity, and teachings that the
people of the north have shown me. I cannot thank you enough. This is for you.
vi
Chapter Acknowledgments
This thesis contains four co-authored manuscripts that are in preparation, in review, or
have been published in peer-reviewed journals. I obtained permission to publish these
articles from their publishers. I designed all research and analysis procedures and wrote
all resulting manuscripts. Co-authors were involved through providing samples and their
associated biological data, guidance and review, and editing.
• Chapter 2: Wong PBY, Cattet MC, Stenhouse G, Erdmann N, Murphy RW.
Telomeres as an indicator of aging and oxidative stress in grizzly bears. In
preparation.
• Chapter 3: Wong PBY, Murphy RW. Telomere variation in polar bears: the effect
of age, sex, and population in tissues harvested by Inuit hunters. In preparation.
• Chapter 4: Wong PBY, Murphy RW. 2016. Inuit methods of identifying polar
bear characteristics: potential for Inuit inclusion in polar bear surveys. Arctic. In
press.
• Chapter 5: Wong PBY, Arviat Hunters and Trappers, Ikajutit Hunters and
Trappers, Mayukalik Hunters and Trappers, Dyck MG, Murphy RW. Inuit
perspectives of polar bear research: lessons for community-based collaborations.
2016. Polar Record. Submitted.
The following independent articles were also published over the course of this research
program:
• Wong PBY. 2016. Traditional ecological knowledge and practice and Red List
assessments: guidelines and considerations for integration. Social Science for
Conservation Fellowship Programme Working Paper 2. The International Union
for Conservation of Nature. In press.
vii
• Tondu JME, Balasubramaniam AM, Chavarie L, Gantner N, Knopp JA,
Provencher JF, Wong PBY, Simmons D. 2014. Working with northern
communities to build collaborative research partnerships: perspectives from early
career researchers. Arctic 67: 419–429.
• Xia Y, Zheng Y, Miura I, Wong PBY, Murphy RW, Zeng X. 2014. The evolution
of mitochondrial genomes in modern frogs (Neobatrachia): nonadaptive evolution
of mitochondrial genome reorganization. BMC Genomics 15: 691–675.
• van Coeverden de Groot P, Wong PBY, Harris C, Dyck MG, Kamookak L, Pagès
M, Michaux J, Boag PT. 2013. Toward a noninvasive Inuit polar bear survey:
genetic data from polar bear hair snags. Wildlife Society Bulletin 37: 394–401.
• Wong PBY, Wiley EO, Johnson WE, Ryder OA, O’Brien SJ, Haussler D,
Koepfli KP, Houck M, Perelman P, Mastromonaco G, Bentley AC, Venkatesh B,
Zhang YP, Murphy RW. 2012. Tissue sampling and standards for vertebrate
genomics. GigaScience 1: 8–20.
• Wong PBY, van Coeverden de Groot P, Fekken C, Boag PT. 2011. Polar bear
(Ursus maritimus) tracking techniques of Inuit hunters: interrater reliability and
inferences on accuracy. Canadian Field Naturalist 125: 140–153.
viii
Table of Contents
Acknowledgments ........................................................................................................................... iv
Chapter Acknowledgments ............................................................................................................. vi
Table of Contents .......................................................................................................................... viii
List of Figures ................................................................................................................................. xi
List of Tables .................................................................................................................................. xii
List of Appendices ........................................................................................................................ xiii
List of Abbreviations ...................................................................................................................... xv
Introduction and context ............................................................................................................ 1 1
1.1 Telomeres as an indicator of biological and/or chronological aging .................................. 2
1.2 Methods of telomere measurement ..................................................................................... 5
1.3 Thesis objectives ................................................................................................................. 6
1.4 Synthesis of chapters .......................................................................................................... 8
Development of a telomere restriction fragment assay in grizzly bears: telomeres as an 2indicator of aging, sex, and oxidative stress .................................................................................. 10
2.1 Summary ........................................................................................................................... 10
2.2 Introduction ...................................................................................................................... 10
2.3 Development of a TRF assay ............................................................................................ 13
2.4 Results .............................................................................................................................. 16
2.5 Discussion ......................................................................................................................... 22
2.6 Appendix .......................................................................................................................... 28
A qPCR assay of telomeres comparing tissue-type, age, sex, and population in polar bears . 31 3
3.1 Summary ........................................................................................................................... 31
3.2 Background ....................................................................................................................... 32
3.3 Methods ............................................................................................................................ 35
3.3.1 QPCR in samples of wild polar bears ........................................................................ 35
ix
3.3.2 Comparisons between TRF and qPCR assays ........................................................... 40
3.4 Results .............................................................................................................................. 41
3.4.1 Telomeres in harvested polar bears based on qPCR ................................................. 41
3.4.2 Comparisons between TRFs and T/S ........................................................................ 55
3.5 Discussion ......................................................................................................................... 56
3.6 Appendix .......................................................................................................................... 62
3.6.1 Development of a TRF assay of captive (zoo) polar bear samples ........................... 62
3.6.2 Supplementary analyses ............................................................................................ 65
3.6.3 Age, sex, and stress effects on grizzly bear telomere length using qPCR ................. 67
3.6.4 QPCR data and standard curves for six telomere and reference primer plates ......... 71
3.6.5 Model selection for telomere length .......................................................................... 97
Inuit methods of identifying polar bear characteristics: potential for Inuit inclusion in polar 4bear surveys .................................................................................................................................... 99
4.1 Summary ........................................................................................................................... 99
4.2 Polar bear conservation and harvest management in Nunavut ......................................... 99
4.3 Methods .......................................................................................................................... 103
4.4 Results ............................................................................................................................ 108
4.4.1 Hunter preference for bear characteristics ............................................................... 110
4.4.2 Methods of identifying polar bear characteristics ................................................... 114
4.5 Discussion ....................................................................................................................... 127
4.5.1 The role of Inuit methods of identifying polar bear characteristics in monitoring programs ............................................................................................................................... 127
4.5.2 Comparisons between Inuit methods of identifying characteristics and science .... 129
4.5.3 The role and persistence of Inuit knowledge in polar bear management ................ 131
4.5.4 Barriers to Inuit inclusion in polar bear research .................................................... 133
4.6 Appendix ........................................................................................................................ 135
4.6.1 Participant responses to interview questions ........................................................... 135
x
Inuit perspectives of polar bear research: lessons for community-based collaborations ...... 141 5
5.1 Summary ......................................................................................................................... 141
5.2 Background ..................................................................................................................... 141
5.3 Methods .......................................................................................................................... 145
5.4 Results ............................................................................................................................ 146
5.4.1 Cultural factors affecting participant responses to research questions .................... 147
5.4.2 Inuit observations of polar bear ecology ................................................................. 149
5.4.3 Management perspectives and recommendations for polar bear research .............. 152
5.5 Discussion ....................................................................................................................... 158
5.5.1 Lessons learned from community-based interactions ............................................. 158
5.5.2 Overlaps between polar bear TEK with science and other TEK studies ................. 160
5.5.3 Challenges and considerations for polar bear monitoring and research methods ... 162
5.5.4 Concluding remarks for northern community-based research ................................ 165
Synthesis of chapters and concluding discussion .................................................................. 168 6
6.1 Summary of chapters ...................................................................................................... 168
6.2 Telomeres as an indicator of biological senescence ....................................................... 169
6.3 Inuit methods of estimating polar bear health as potential indicators of biological senescence ................................................................................................................................ 172
6.4 Conclusions .................................................................................................................... 173
References .................................................................................................................................... 175
xi
List of Figures
Figure 1. A sample TRF gel of 18 grizzly bear samples showing a sample analysis window ....... 19
Figure 2. Non-significant and significant linear regressions of age on mean TRF length (in kilobase pairs) in 14 males and seven females, respectively ............................................................ 20
Figure 3. A sample gel showing little to no signal in samples with compared to samples without BAL-31 exonuclease digestion ................................................................................................................... 21
Figure 4. A graph showing a significant model II regression between mean TRF length with and without BAL-31 exonuclease digestion in nine grizzly bear samples ........................................... 22
Figure 5. A map showing distributions of Nunavut communities among 16 of 19 global polar bear populations (Laptev, Kara, and Barents Sea populations not shown) ........................................... 35
Figure 6. A graph of a significant model II regression between heart and muscle T/S in 39 polar bears .................................................................................................................................................................... 44
Figure 7. A graph of a significant model II regression between heart and skin T/S in 40 polar bears. ................................................................................................................................................................... 45
Figure 8. A graph of a significant model II regression between muscle and skin T/S in 39 polar bears .................................................................................................................................................................... 46
Figure 9. A graph showing significant differences in heart T/S across polar bear populations ..... 48
Figure 10. A box plot comparing muscle T/S among age groups in 10 females (F) and 30 males (M). ...................................................................................................................................................................... 50
Figure 11. A graph showing significant differences in muscle T/S across polar bear populations. ............................................................................................................................................................................... 53
Figure 12. A qualitative comparison of heart, muscle, and skin T/S across communities ............... 54
Figure 13. A graph of a non-significant model II regression between mean TRF length and blood T/S measured in 14 grizzly bears .............................................................................................................. 56
Figure 14. A map displaying Gjoa Haven (1), Kugaaruk (2), Arctic Bay (3), Kimmirut (4), and Arviat (5) communities where participants were interviewed for this study ............................ 106
xii
List of Tables
Table 1. A general linear model for the effect of age, sex, HCC, GGT, and the interaction between age and sex on mean TRF length in 21 grizzly bears ........................................................ 18
Table 2. Linear regressions for the effect of age on mean TRF length in 14 male and seven female grizzly bears. .................................................................................................................................................... 18
Table 3. A one-way analysis of variance using type III sums of squares showing significant differences in heart T/S among Baffin Bay (N=10), Davis Strait (N=6), Foxe Basin (N=5), Lancaster Sound (N=9), and Western Hudson Bay (N=10) polar bear populations. ............... 47
Table 4. A multi-factor analysis of variance using type III sums of squares showing significant effects of age, sex, population, and the interaction between age and sex on muscle T/S in 39 polar bears. ........................................................................................................................................................ 49
Table 5. One-way analyses of variance using type III sums of squares showing non-significant differences in muscle T/S among age groups in 29 male and 10 female polar bears. ............. 49
Table 6. A multi-factor analysis of variance using type III sums of squares showing non-significant effects of age, sex, and the interaction between age and sex and a significant effect of population on skin T/S in 40 polar bears. .............................................................................. 52
Table 7. Interview guideline. .............................................................................................................................. 107
Table 8. Number of interview participants from Gjoa Haven, Arctic Bay, Kimmirut, and Arviat corresponding to participant type, hunting experience, and having mentioned experience guiding sport hunts during interviews .................................................................................................... 110
xiii
List of Appendices
Appendix 1. Mean TRF length in 21 grizzly bears corresponding to mean TRF length, age, sex, and measurements of stress hormones (hair cortisol concentration [HCC] and serum gamma-glutamyltransferase [GGT]). ....................................................................................................................... 28
Appendix 2. Akaike Information Criterion (AIC) and difference in AIC compared to the most parsimonious model for models of mean TRF length in 21 grizzly bears ................................... 29
Appendix 3. Mean TRF length in 9 grizzly bears corresponding to mean TRF length with BAL-31 exonuclease treatment, digesting terminal telomere sequences. ..................................................... 30
Appendix 4. A TRF gel of polar bears samples provided by zoos. Samples are labeled at the top of each lane, as well as a negative control .............................................................................................. 64
Appendix 5. Results from non-significant paired t-tests comparing T/S among polar bear heart, muscle, and skin tissues (N=40, 39, and 40 individuals, respectively). ........................................ 65
Appendix 6. A one-way analysis of variance using type III sums of squares showing the significant effect of population on heart T/S in 39 polar bears (one outlier was excluded from the original sample of 40). ........................................................................................................................... 65
Appendix 7. A multi-factor analysis of variance using type III sums of squares showing significant effects of age, sex, population, and the interaction between age and sex on muscle T/S in 38 polar bears (one outlier was excluded from the original sample of 39). ................... 66
Appendix 8. Blood T/S measured from qPCR and mean TRF length (in kilobase pairs) measured from TRF assays in 17 grizzly bear samples (nine males and eight females) ............................ 68
Appendix 9. A general linear model for the effect of age, sex, HCC, GGT, and the interaction between age and sex on blood T/S in 17 grizzly bears. Effects were not significant. ............. 69
Appendix 10. A graph showing non-significant linear regressions between blood T/S and age in 17 grizzly bears ................................................................................................................................................ 70
Appendix 11. Polar bear samples collected by Inuit hunters for qPCR corresponding to community that provided the sample, population where the sample was harvested, age, and sex diagnoses .................................................................................................................................................... 71
Appendix 12. Cycle threshold values (Ct) for Plate 1 of 6 telomere (telc/telg) and reference (RPLP0-F1/RPLP0-R1) qPCR assays ..................................................................................................... 73
Appendix 13. Cycle threshold values (Ct) for Plate 2 of 6 telomere (telc/telg) and reference (RPLP0-F1/RPLP0-R1) qPCR assays ..................................................................................................... 77
Appendix 14. Cycle threshold values (Ct) for Plate 3 of 6 telomere (telc/telg) and reference (RPLP0-F1/RPLP0-R1) qPCR assays ..................................................................................................... 81
xiv
Appendix 15. Cycle threshold values (Ct) for Plate 4 of 6 telomere (telc/telg) and reference (RPLP0-F1/RPLP0-R1) qPCR assays ..................................................................................................... 85
Appendix 16. Cycle threshold values (Ct) for Plate 5 of 6 telomere (telc/telg) and reference (RPLP0-F1/RPLP0-R1) qPCR assays ..................................................................................................... 89
Appendix 17. Cycle threshold values (Ct) for Plate 6 of 6 telomere (telc/telg) and reference (RPLP0-F1/RPLP0-R1) qPCR assays. .................................................................................................... 91
Appendix 18. Melt curves for seven dilutions ranging from 0.0064 to 10ng per reaction in duplicate (14 reactions) showing a single peak, confirming specificity of telomere (telc/telg) primers. ............................................................................................................................................................... 94
Appendix 19. Melt curves for seven dilutions ranging from 0.0064 to 10ng per reaction in duplicate (14 reactions) generally showing a single peak, confirming specificity of reference (RPLP0-F1/RPLP0-R1) primers. ............................................................................................................... 96
Appendix 20. Characteristics of standard curves six telomere (telc/g) and reference (RPLP0 [F1/R1]) qPCR plates .................................................................................................................................... 97
Appendix 21. Akaike Information Criterion (AIC) and difference in AIC compared to the most parsimonious model (ΔAIC) for models of heart T/S in 40 polar bears ...................................... 97
Appendix 22. Akaike Information Criterion (AIC) and difference in AIC compared to the most parsimonious model (ΔAIC) for models of muscle T/S in 39 polar bears .................................. 98
Appendix 23. Akaike Information Criterion (AIC) and difference in AIC compared to the most parsimonious model (ΔAIC) for models of skin T/S in 40 polar bears ........................................ 98
xv
List of Abbreviations
AB Arctic Bay
AIC Akaike Information Criterion
ANOVA analysis of variance
AR Arviat
BB Baffin Bay
Ct cycle threshold
CV coefficient of variation
DS Davis Strait
EDTA ethylenediaminetetraacetic acid
FB Foxe Basin
GH Gjoa Haven
HCC hair cortisol concentration
HSD Honest Significant Difference
HTO Hunters and Trappers Organization
INAC Indian and Northern Affairs Canada
IQ Inuit qaujimajatuqangit
K Kimmirut
KU Kugaaruk
GGT serum gamma glutamyltransferase
LS Lancaster Sound
PCR polymerase chain reaction
qPCR quantitative polymerase chain reaction
T/S telomere repeat to single copy gene ratio
TEK traditional ecological knowledge
TRF telomere restriction fragment assay
WHB Western Hudson Bay
1
Chapter 1
Introduction and context 1
Polar bear responses to climate-induced habitat changes have been uncertain and subject
to debate among scientific (Dyck et al. 2007, Stirling et al. 2008) and Inuit (Dowsley
2009a) communities. The absence of range-wide data on population size and sustainable
harvest rates may explain these uncertainties (Peacock et al. 2011, Vongraven and
Peacock 2011). Conservation and management of polar bears are based on aerial mark-
recapture surveys of 19 populations defined by a combination of landscape patterns
(Ferguson et al. 1998), genetic differences (Paetkau et al. 1999), and movements of
individuals (Taylor et al. 2001). While useful for projecting sex and age distributions,
mark-recapture surveys are invasive, expensive (Dowsley 2009a), and infrequently
implemented (Peacock et al. 2011). Polar bears from these studies are aged from tooth
growth patterns that vary in accuracy and precision (Christensen-Dalsgaard et al. 2010).
Less-invasive, remote biopsy dart surveys facilitate genetic sexing and genotyping of
individual bears (Wong et al. 2011, Van Coeverden de Groot et al. 2012, Pagano et al.
2014). However, molecular-based methods of age estimation await development.
Age distributions are necessary to predict survival and recruitment (reproductive)
rates (Taylor et al. 2006, Regehr et al. 2007, Hunter et al. 2010) and impacts of
harvesting (McLoughlin et al. 2005, Taylor et al. 2005, Taylor et al. 2008) that together
inform conservation and management policies. The ability to detect rapid changes in age
structure is also critical to monitor long-term impacts of hunting selection on population
dynamics, ensure sustainable yields, and avoid reductions in desirable phenotypes
(Allendorf et al. 2008, Allendorf and Hard 2009). For most long-lived, polygynous
species, harvesting more males than females can presumably evade decreases in
fecundity and protecting young animals can ensure chances of survival to reproduction
(Caughley and Sinclair 1994). In Nunavut, polar bears are harvested at a 2:1 male to
female ratio to protect females and cubs (Taylor et al. 2008, Peacock et al. 2011). While
hunter-selected phenotypes (e.g., large body sizes, fur quality) may correspond to age and
2
sex, it is critical to understand the drivers of hunter selection and the means of accurately
identifying these population parameters, especially for harvested animals.
1.1 Telomeres as an indicator of biological and/or
chronological aging
Over 300 theories of why aging occurs have been proposed yet no theory alone is
sufficient (Medvedev 1990, Kirkwood et al. 2005). A holistic understanding of the
multiple intra- and inter-individual aging phenotypes in nature is inherently complex and
requires an integration of evolutionary and physiological perspectives (Medvedev 1990,
Kirkwood et al. 2005). From an evolutionary standpoint, a question of interest is how and
why forces of selection have not eliminated aging (Medvedev 1990). An explicit theory
was put forth by Medawar (1952) who synthesized ideas from Fisher (1930) and Haldane
(1941), which posits that aging occurs as a result of mutation accumulation; forces of
selection for long life-span weaken with age due to accumulating deleterious mutations
expressed at older ages. Williams (1957) suggested aging might be explained by
antagonistically pleiotropic genes that, while incurring deleterious effects in older
individuals, are maintained due to their contributions to the survival and fecundity of
younger individuals. Kirkwood (1977) proposed an integrative, evolutionary-
physiological theory that posits that organisms must optimize a balance between
maintaining the soma (e.g., against wear-and-tear associated with life itself) and other
activities that maximize Darwinian fitness (e.g., reproduction). In other words, organisms
must allocate limited resources toward activities that minimize versus contribute to aging.
The associated age-related trade-offs should also reflect extrinsic mortality risks (e.g.,
nutrient availability, predation, competition, etc.), which together underlie determinants
of longevity (Ricklefs 1998, Kirkwood 2005, Eisenberg 2010). For example, an
individual would benefit from investing any available energy beyond what is required to
physiologically maintain a reasonable chance of survival in the wild into reproduction,
rather than somatic maintenance, in an environment with high extrinsic risks of mortality.
The free radical theory of aging explains this trade-off. It posits that cellular damage from
reactive oxygen species over time or in response to stress contributes to cellular
3
dysfunction and death (Harman 1956, Kirkwood and Kowald 2012). As a stress response,
reactive oxygen species allow organisms to mobilize energy toward efforts that
encourage immediate survival (e.g., increasing foraging effort and food access in stressful
environments [Romero 2004]), at the expense of biological integrity (Shigenaga et al.
1994, Monaghan et al. 2009). These theories of aging refer to biological senescence,
defined here as progressive physiological deterioration (wear-and-tear) and, hence,
increase in mortality risk (Kirkwood 2005), whereas chronological aging refers to an
external measure of time (since birth).
Telomere attrition may serve as one proximate mechanism that mediates the
trade-off between self-maintenance, or prolonging lifespan, and aging. Telomeres are
repetitive guanine-rich DNA sequences (5’-[TTAGGG]n-3) associated with structural and
regulatory proteins with a 3’ single-stranded overhang at the ends of chromosomes
(Blasco 2005, de Lange et al. 2010, Dunshea et al. 2011, Gomes et al. 2011). Telomeres
shorten with cell division due to the inability of DNA replication machinery (DNA
polymerase) to replicate terminal ends of linear chromosomes (Monaghan and
Haussmann 2006, de Lange et al. 2010, Eisenberg 2010). This progressive shortening
eventually leads to cellular senescence––impairing cell and/or tissue function through the
alteration of gene expression and accumulation of senescent cells, respectively––and
hence aging phenotypes and individual death (Harley et al. 1990; Monaghan and
Haussmann 2006, Dunshea et al. 2011). Telomeres serve as functionally important
“caps” at the ends of chromosomes to protect genome integrity against DNA replication.
Telomeres also protect DNA from oxidative degradation and recognition of chromosomal
ends as double-stranded breaks, which initiates detrimental DNA repair responses
(Harley et al. 1990, Monaghan and Haussmann 2006, Dunshea et al. 2011). Telomeres
are particularly prone to oxidative damage as oxidative intermediates (reactive oxygen
species) preferentially target guanine triplets (GGG) and DNA damage repair is less
efficient along telomeres than along interstitial regions of DNA (Shay and Wright 2007).
Telomere maintenance and elongation occurs by activating the enzyme
telomerase (a reverse-transcriptase enzyme with an RNA template component) or
4
alternative lengthening mechanisms, such as homologous recombination between
telomeres (de Lange et al. 2006, Blasco 2007). Long telomeres are advantageous because
they maximize cell proliferation potential, particularly in tissues where cell regeneration
is needed, for example, in blood cells (lymphocytes) that are required for immune
function (Kaszubowska 2008). However, long telomeres are costly—requiring energy
and resources—to maintain through cell division (de Lange et al. 2006, Kaszubowska
2008, Eisenberg 2010). Continuous cell division associated with long telomere lengths
may also incur damaging (e.g., cancerous) effects (Aviv 2006, Monaghan and
Haussmann 2006, Eisenberg 2010, Gomes et al. 2011). Telomerase activity and
alternative lengthening pathways are activated only in embryonic and germ-line cells—
tissues vital to survival and fecundity—and are generally rare or inactive in most somatic
cells (de Lange et al. 2006, Dunshea et al. 2011).
While evidence for a relationship between telomere length and chronological age
exist, several factors caution against the use of telomere length to predict chronological
age (Horn et al. 2010, Dunshea et al. 2011, Nussey et al. 2014). Evidence for telomere
shortening leading to cellular senescence in humans has been reported extensively
(Harley et al. 1990, de Lange et al. 2006, Eisenberg 2010). Research across taxa––for
example, primates (Herbig 2006), birds (Haussmann et al. 2003, Bize et al. 2009), fish
(Horn et al. 2008), reptiles (Scott et al. 2006, Hatase et al. 2008, Olsson et al. 2011, Plot
et al. 2012), sea lions (Izzo 2011), and whales (Olsen et al. 2014), as well as domestic
sheep, cattle, mice, and dogs (Haussman et al. 2002)––reveal an effect of chronological
age on telomere length. Telomere length has also been linked to survival (by re-sampling
individuals across time; e.g., Foote et al. 2010), lifespan (e.g., Heidinger et al. 2012)
and/or fecundity (e.g., clutch size; Scott et al. 2006, Voillemot et al. 2012, Bauch et al.
2013). However, variation in telomere length among (e.g., Vleck et al. 2003, Juola et al.
2006, Hewakapuge et al. 2008) and within (e.g., Prowse and Greider 1995, Betts et al.
2001, Lin et al. 2010) individuals of the same age across some taxa suggest telomere
patterns may serve as a more appropriate indicator of biological versus chronological
aging. For example, short telomeres have been linked to diseases that increase mortality
such as heart (Oh et al. 2003) and liver (Wiemann et al. 2002) failure and obesity (Valdes
5
et al. 2005), as well as psychological health disorders (e.g., Epel et al. 2004). Telomere
lengths may also vary with tissue-type (Mather et al. 2010), sex (Blasco 2007, Barrett
and Richardson 2011), environment (Monaghan 2010), and/or maternal/paternal
inheritance (Eisenberg 2010, Olsson et al. 2011). Attempts to quantify these patterns in
vivo in ursids—and large carnivores in general––are lacking (but see Lewin et al. 2015,
Beirne et al. 2016).
1.2 Methods of telomere measurement
The “gold standard” of measuring telomeres is the telomere restriction fragment (TRF)
method (Horn et al. 2010, Monaghan 2010, O’Callaghan et al. 2011). TRF assays involve
digesting DNA with restriction enzymes that do not cut within the telomere sequence
(Dunshea et al. 2011, Gomes et al. 2011) and separating the DNA fragments through gel
electrophoresis (Kimura et al. 2010). As restriction enzymes cleave DNA at various
distances from the telomere and telomere lengths vary across all chromosomes, a smear is
produced versus a sharp band to calculate mean telomere length (Juola et al. 2006, Horn
et al. 2010). Telomeres are then detected by hybridizing denaturing probes to telomeric
sequences that have been separated into single strands (Kimura et al. 2010) or non-
denaturing probes to the 3’ single-stranded overhang of telomeres (Herbert et al. 2003);
the latter protocol is applicable for species with interstitial telomeric repeats in non-
telomeric regions of DNA (Herbert et al. 2003). On the one hand, TRF assays are
attractive as they allow for analyses of telomere length distributions across all
chromosomes (Haussmann and Mauck 2008), where mean telomere length measurements
can provide inferences on general phenotypes (e.g., somatic fitness; Aviv 2006). On the
other hand, TRF assays are time-consuming and require large amounts of DNA (from
2µg for denaturing to 10µg for nondenaturing protocols; Monaghan 2010, Dunshea et al.
2011). TRF assays can also vary in choice of restriction enzymes, probes and
hybridization targets, quantification methods, and the analysis window selected (Horn et
al. 2010). Alternative methods based on fluorescent in situ hybridization (FISH) and
polymerase chain reaction (PCR) have been developed, yet FISH (e.g., quantitative or
flow FISH) and some PCR-based (e.g., single telomere length analysis) methods are
6
expensive and require expert knowledge of the associated equipment and protocols
(Nakagawa et al. 2004, Kimura et al. 2010, Dunshea et al. 2011, Montpetit et al. 2014).
Real time quantitative PCR (qPCR; Cawthon 2002, Cawthon 2009) is attractive
because it requires small initial DNA quantities to generate high-throughput data (Kimura
et al. 2010, Dunshea et al. 2011). Using estimates of telomere repeat quantities (T) in
relation to a single copy reference gene (S) across chromosomes and cells, this technique
determines a relative telomere length estimate expressed as a ratio (T/S; Cawthon 2002,
Cawthon 2009, Monaghan 2010). Telomere and reference quantities are determined using
a standard linear curve, which is derived from serial dilutions of a standard (high quality)
sample of known quantity, in relation to the threshold number of cycles that is required to
detect a fluorescent signal released by the amplified products (Ct; Bustin et al. 2009,
Bustin et al. 2013). Larger quantities of a target sequence (longer telomeres) require
fewer cycles for fluorescence detection. For singleplex methods (Cawthon 2002),
variation in telomere and/or single copy gene PCR efficiency influences reliability in the
resulting measurements (Horn et al. 2010, Dunshea et al. 2011) and T/S calculations
must incorporate efficiency (for each reaction plate and primer; Pffafl 2001). While
recent advances allow for multiplex (Cawthon 2009) and absolute quantification
(O’Callaghan et al. 2011) techniques, multiple methods of baseline corrections for qPCR
outputs (Ruitjer et al. 2009) and quantification (Pffafl 2009, Olsen et al. 2012) result in
several possible combinations of telomere measurement procedures (Horn et al. 2010,
Nussey et al. 2014). Any telomere measurement technique must be selected and
optimized according to the resources that are available and the life-history of the species
(Montpetit et al. 2014, Nussey et al. 2014).
1.3 Thesis objectives
At a proximate level, genetic and environmental components shape individual
physiological functioning that may ultimately determine an organism’s life span. In
conservation contexts, understanding the factors that contribute to biological senescence
can provide insight into external mortality risk and population persistence. Using
7
telomeres as an indicator of biological senescence, this thesis examines telomere length
variation as a function of tissue type, chronological age, sex, stress, and environmental
differences using a combination of TRF and qPCR assays. Specifically, I address the
following questions:
• How does telomere length vary with age, sex, and indicators of stress, using a
TRF assay in grizzly bears (Chapter 2)?
• How does telomere length vary with tissue-type, age, sex, and population in
harvested polar bears, using a qPCR assay (Chapter 3)?
Polar bear samples were provided through a community-level, harvest-monitoring
program in Nunavut. To enrich my scientific findings, determine conservation relevance
for management applications, and explore capacity for long-term community-level
collaborative research programs, my thesis includes a qualitative, multidisciplinary
approach to also examine the following topics:
• Inuit methods of identifying polar bear age, sex, body size, and health and the role
of Inuit knowledge in polar bear surveys (Chapter 4).
• Inuit perspectives of and recommendations for polar bear research and
management (Chapter 5).
By addressing these questions, my research not only evaluates telomeres as a marker of
biological aging, but also includes Inuit traditional ecological knowledge (TEK) of polar
bears as a complementary approach to monitoring and conserving threatened species.
While including Inuit experience and perspectives highlights considerations for polar
bear research, monitoring, and management that would not be available through science
alone, TEK offers different and unique interpretations of ecological information than
those based on standard Western scientific methods. In these contexts, my research uses
novel, multidisciplinary methods to link scientific and Inuit knowledge of polar bear
ecology to examine the multiple factors that are involved in biological aging.
8
1.4 Synthesis of chapters
In Chapter 2, I report on efforts to develop a TRF assay using wild grizzly bear samples
that were collected by collaborators from the University of Saskatchewan (M. Cattet) and
Foothills Research Institute (G. Stenhouse) during independent, routine mark-recapture
surveys in 2012 and 2013. Due to relative ease in collecting and storing high quality
grizzly bear samples required for genetic analysis (e.g., fresh blood frozen at -80°C;
Wong et al. 2012) and TRF assays (Kimura et al. 2010), this work serves to initially
characterize telomeres as a marker of aging in ursids. I also explore potential effects of
oxidative stress on telomeres. I test the null hypothesis that age, sex, and indicators of
acute and chronic stress on grizzly bears do not affect telomere length.
In Chapter 3, I describe a qPCR assay of salvaged polar bear heart, muscle, and
skin samples from the same wild individuals provided by Government of Nunavut
Department of Environment collaborators (M. Dyck). These samples do not yield
sufficient DNA quality for TRF assays and, thus, I use qPCR to explore the feasibility of
conducting telomere assays using harvest samples. I test the null hypotheses that telomere
lengths do not differ with tissue-type and across age, sex, and population groups in
different tissues for polar bears.
The inclusion of Inuit TEK of polar bears can enrich scientific findings, ensure
social and policy relevance, and, more importantly, reveal novel ecological perspectives
and monitoring techniques that are not available through conventional scientific methods.
In Chapter 4, I summarize and report Inuit methods of identifying polar bear sex, age,
body size, and health across four Nunavut communities. While Inuit experiences provide
insight into hunter selection and polar bear ecology and behaviour, Inuit methods of
identifying individual characteristics can provide rapid, inexpensive population
information.
As relationships with Inuit communities are necessary to sustain long-term
research collaborations and monitoring programs, as well as encourage support for
9
research outputs (e.g., management decisions), in Chapter 5 I report Inuit experiences
with polar bears and management perspectives. These interviews provide Inuit with the
opportunity to voice their perspectives and concerns, independently from science.
In chapter 6, I summarize major findings and their implications, and discuss
opportunities to build on this research. I discuss scientific and Inuit methods of tracking
biological senescence in polar bears. I also highlight alternative scientific approaches and
potential applications of this work within the context of polar bear monitoring and
management.
10
Chapter 2
Development of a telomere restriction fragment 2
assay in grizzly bears: telomeres as an indicator
of aging, sex, and oxidative stress
2.1 Summary
Accurate and reliable life-history information in addition to data on population dynamics
is critical for grizzly bear management and conservation. As in polar bears (and other
large carnivores of conservation concern), genetic-based methods of collecting these data
are particularly attractive because they are based on noninvasive sampling techniques.
Currently, methods of determining age are still not developed for noninvasive tissues;
telomeres could serve as a biomarker of aging. I report on efforts to develop the first
telomere restriction fragment measurement assay in wild grizzly bears—and ursids in
general—to determine the effect of age, sex, and indicators of stress (hair cortisol [HCC]
and serum gamma-glutamyltransferase [GGT] concentration) on mean telomere length in
21 (14 male and seven female) individuals ranging from 1.4 to 15.7yr old. Sex, HCC and
GGT effects were not significant, though age effects were significant overall. Age effects
were not significant in males but significant in females, who showed a slight increase in
telomere length with age (0.21kb per year). These results are inconclusive due to small
sample sizes and high inter-assay variation (17.80%). Further investigation is warranted
in a larger sample size with the inclusion of additional life-history data, where telomeres
might be more appropriately used to implicate biological senescence versus chronological
age.
2.2 Introduction
Understanding population dynamics as they relate to human activities, ecological and
environmental changes, and management programs is critical for grizzly bear (Ursus
11
arctos) conservation and management (Coleman et al. 2013, Boulanger and Stenhouse,
2014). Grizzly bears are vulnerable to population declines due to their late maturation,
low density of occurrence, large geographic range sizes and low reproductive rates
(Woodruffe 2000, Garshelis et al. 2005, Whittington and Sawaya 2015). Grizzly bear
populations have declined substantially across their range in North America (Mattson and
Merrill 2002, Laliberte and Ripple 2004). In Alberta, where grizzly bears are currently
listed as a threatened species (Alberta Sustainable Resource Development and Alberta
Conservation Association 2010), human-induced mortalities are believed to be the
highest contributing factor to population decline and vulnerability (Nielsen et al. 2004,
Proctor et al. 2012, Apps et al. 2015). At a broad scale, anthropogenic development (e.g.,
resource extraction activities, including oil and gas exploration, timber harvesting, and
mining [Nielsen et al. 2004]) has fragmented habitats (Proctor et al. 2012). At smaller
scales, human-induced mortalities near development sites are frequent due to human-bear
interactions (e.g., human-bear conflicts, legal and illegal harvesting, and bear-vehicle
collisions [Apps et al. 2015]). Human development and exploitation within the broad
range of this species are expected to persist if not increase in the future (Nielsen et al.
2004; Stelfox et al. 2005, Roever et al. 2008, Apps et al. 2015), which will likely
contribute to sink populations (high death and emigration rates; Donovan and Thompson
2001, Naves et al. 2003) and further reduce survival (Garshelis et al. 2005). Indeed, there
is a need for wildlife managers to monitor bear populations in a frequent and cost-
effective way.
For grizzly bears, monitoring life-history traits (e.g., survival and recruitment) in
addition to population growth and occurrence is necessary to identify core habitats of
conservation value and sites of high mortality risk (Naves et al. 2003), as descriptions of
species-occurrence alone do not imply habitat relationships (Nielsen et al. 2003, Nielsen
et al. 2006, Doak and Cutler 2014). Data that can predict population parameters (e.g., sex
and age structure, and morphometry) have been collected through mark-recapture surveys
(e.g., Nielsen et al. 2013, Stenhouse and Graham 2013), telemetry studies (e.g., Mace et
al. 2012, Bourbonnais et al. 2014), and published occupancy records (e.g., government
management databases) as they relate to habitat occurrence (Nielsen et al. 2002, Naves et
al. 2003, Nielsen et al. 2003, Posillico et al. 2004, Nielsen et al. 2006). However, capture
12
and handling of bears is not always favourable due to their potential long-term effects on
physiology and behaviour (Cattet et al. 2003, Arnemo et al. 2006, Cattet et al. 2008a,
Cattet et al. 2008b). Noninvasive alternatives have been developed to estimate population
size and growth (Woods et al. 1999, Mowat and Strobeck 2000, Boulanger et al. 2004,
Macbeth et al. 2010, Sawaya et al. 2012, Rovang et al. 2015, Apps et al. 2015) using
genetic methods of identifying individual (e.g., Paetkau 2003) and sex (e.g., Woods et al.
1999) of bears, as well as parent-offspring relationships (Apps et al. 2015), and by using
endocrine indicators of stress and reproduction (Macbeth et al. 2010, Bryan et al. 2014).
These methods are attractive because they do not require capturing bears, yet can also be
used to link spatial distribution to habitat (e.g., anthropogenic and topographic) features
(Apps et al. 2004, Apps et al. 2015, Rovang et al. 2015). Despite the above, genetic-
based methods of identifying age and stress of individuals have not been developed for
grizzly bears. Current methods of age estimation are based on cementum analysis of pre-
molar teeth extracted during physical capture (Stoneberg and Jonkel 1966, Stenhouse and
Graham 2013). Methods of quantifying stress are based on measuring hormone
concentrations in biological samples, for example, hair snags and blood (Möstl and Palme
2002, Cattet et al. 2003, Macbeth et al. 2010, Beaulieu and Constantini 2014).
Telomeres could serve as a marker of chronological age (Harley et al. 1990,
Haussmann et al. 2002, de Lange et al. 2006, Herbig 2006, Scott et al. 2006, Hatase et al.
2008, Horn et al. 2008, Bize et al. 2009, Eisenberg 2010, Izzo et al. 2011, Olsson et al.
2011, Olsen et al. 2014) and also stress exposure. One response to stress is to stimulate
the hypothalamic-pituitary-adrenal axis to release stress hormones (e.g., glucocorticoids),
which in turn stimulate metabolic responses toward immediate survival (Macbeth 2010,
Beaulieu and Constantini 2014). This results in an increase in the production of reactive
oxygen species as a by-product of mitochondrial metabolism (Mabeth 2010, Beaulieu and
Constantini 2014). Telomeres are particularly prone to oxidative damage by reactive
oxygen species (von Zglinicki 2002, Epel et al. 2004) and indicators of acute (e.g., serum
gamma-glutamyl transferase [Cattet et al. 2003]) and chronic (e.g., hair cortisol [Macbeth
et al. 2010, Beschøft et al. 2011]) oxidative stress could contribute to telomere shortening
(Shalev et al. 2013, Gotlib et al. 2015).
13
To evaluate telomeres as a potential marker of aging and stress in ursids, I report
on efforts to develop a telomere restriction fragment (TRF) assay in grizzly bears of
known age and sex. Tissues of high quality and replicative potential (e.g., fresh, whole
blood) are critical for this initial work (Nussey et al. 2014) prior to applications in other
(e.g., noninvasively) collected tissues. This method has potential to provide inferences on
biological senescence in polar bears, as well as other ursids of conservation concern.
2.3 Development of a TRF assay
The fRI Research Grizzly Bear Program collected whole blood samples from grizzly
bears during independent mark-recapture surveys in 2012 and 2013 (Stenhouse and
Graham 2013). Samples were collected from wild individuals between Grand Prairie and
Grande Cache, Alberta, in an area known as the Grande Cache Bear Management Area
(Stenhouse and Graham 2013). Individuals were captured via remote drug delivery from
ground or helicopter or by culvert traps fitted with satellite trap alarm systems. Cattet et
al. (2008) detailed capture and handling procedures. Animals were sexed visually and
aged by extracting a premolar tooth and counting cementum annuli (Stoneberg and
Jonkel 1996, Stenhouse and Graham 2013). Age was calculated based on the assumption
that all animals were born on January 1st, and converted to a continuous variable (ordinal
day of capture divided by 365 days). Recaptured individuals were identified by detection
of a transponder (microchip), with a unique alphanumeric code that was inserted by
subcutaneous injection at first capture. Each blood sample was also associated with
serum gamma-glutamyltransferase (GGT; Cattet et al. 2003) and hair cortisol (HCC)
concentration measurements as indicators of acute and chronic oxidative stress,
respectively (Macbeth et al. 2010, Bechøft et al. 2011, Cattet et al. 2014). Cattet et al.
(2003) and Cattet et al. (2014) detailed methods for GGT and HCC quantification. For
TRF assays, from 3 to 6ml of blood was collected from the medial saphenous or jugular
vein by venipuncture, transferred to a vacutainer (BD Vacutainer®, BD Diagnostics,
Preanalytical Systems, Franklin Lakes, NJ, USA) containing ethylenediaminetetraacetic
acid (EDTA) as a preservative, and then stored at -80°C until processing.
14
I isolated genomic DNA from blood samples using a Gentra Puregene Blood
extraction kit (QIAGEN 158389) following manufacturer’s instructions at the University
of Toronto (J. Stinchcombe Lab). I ran the DNA samples out on 1% (w/v) agarose gels to
ensure they were of sufficient quality (no evidence for degradation; Kimura et al. 2010)
at the Royal Ontario Museum Laboratory of Molecular Systematics and quantified them
using a Nanodrop spectrophotometer (University of Toronto M. Sokolowski Lab). To
avoid degradation due to repeated freeze-thaw, I divided samples into 2µg aliquots before
storage at -20°C for TRF assays.
I set up TRF assays at the Royal Ontario Museum Laboratory of Systematics;
subsequent labeling, hybridization, and visualization occurred at Princess Margaret
Hospital Ontario Cancer Institute (H. Okada Lab) or University of Toronto (L. Frappier
Lab). TRF assays followed a modification of Kimura et al. (2010)’s Southern blot
analysis technique. Briefly, I digested 2µg samples overnight with HinfI (New England
BioLabs Inc. R0155L) and RsaI (New England Biolabs Inc. R0167L) and ran them on
0.5% agarose gels alongside a high molecular weight ladder (7 to 49kb in range; Sigma-
Aldrich 11721615001) flanking the samples. I ran gels overnight (approximately 20hr) at
40 to 45V to produce a smear of the range of telomere lengths across cells and
chromosomes (Kimura et al. 2010). I transferred the digested DNA to positively charged
Hybond N+ membranes (GE Healthcare Lifesciences RPN119B) through capillary action
(versus suction). I prepared radioactively labeled (P-32 gamma ATP) ladder and telomere
([CCATTT]3) probes and hybridized them to the membranes for 24hr at 37°C. I then
washed the membranes, exposed them to phosphor imager screens for 24hr, and scanned
the imager screens on a Typhoon 9400 Variable Mode Imager (Amersham Biosciences)
to produce images of TRF smears in ImageQuant TL 8.1 (GE Healthcare Lifesciences
29000605). I ran a control human blood sample alongside each TRF assay to determine
inter-assay, coefficient of variation (CV) among replicate TRF assays.
I quantified TRF lengths by densitometry in ImageJ v 1.49 using the equation
telomere length = Σ(ODi)/ Σ (ODi/MWi) for denaturing gels, where ODi and MWi refer to
15
optical density and molecular weight, respectively, at position i (Horn et al. 2010,
Kimura et al. 2010). For each blot, I used the same analysis window for all samples and
ladders, which contained the whole lane excluding regions near the top of the loading
area (undigested DNA). I calculated mean TRF length for each sample twice (one for
each of the two ladders that were run alongside the samples) and calculated weighted
means by horizontal position from each ladder for each sample. I quantified each blood
sample through this full procedure at least three times and included a mean TRF length
across these replicates in subsequent analyses. For samples with more than three
replicates, I selected three replicates at random for inclusion.
To determine the effect of aging and stress, as well as sex, on telomere length, I
determined the most parsimonious model for mean TRF length, using age, sex, HCC, and
GGT as predictors and evaluated their effects. I conducted model selection and all
statistical analyses in R. I began with a saturated model: age, sex, HCC, or GGT and all
two-way interactions, excluding higher-order interactions due to small sample sizes. I
eliminated non-significant predictors using backward selection and maximum likelihood
ratio tests (drop1 in R). I selected the model structure with the lowest Akaike Information
Criterion (AIC; Hurvich and Tsai 1989, Burnham and Anderson 2004). Using plots, I
examined resulting regressions for outliers, normality (e.g., fitting quantile-quantile plots
with normal lines and 95% confidence intervals), and homoscedasticity (e.g., examining
residual plots for random spread of residuals) to determine if data transformations would
be necessary. I used plots instead of statistical tests due to small sample size and, thus,
low power for detecting significance. I tested significant effects of predictors in the final
model using an ordinary least squares linear regression. I also determined the effect of
age on mean TRF length separately in males and females through linear regression.
Significant levels were set at an alpha (P) of 0.05.
To confirm if interstitial telomeric sequences were present in grizzly bears and
would thus affect telomere measurements, I compared TRF lengths with and without
BAL-31 exonuclease digestion—an enzyme that digests terminal (telomeric) ends of
DNA (Bassham et al. 1998, Sykorová et al. 2013)—in a small subgroup of samples that
16
provided sufficient DNA for this analysis. These TRF assays followed the above protocol
except for digestion with BAL-31 following HinfI and RsaI digestion, following
manufacturer instructions (New England Biolabs Inc. M0213S). I conducted a paired t-
test to test for significant differences in mean TRF length with and without BAL-31
treatment. I also conducted a model II regression to examine the relationship between
mean TRF length with and without BAL-31 treatment and tested for significant
differences from a slope of 1 and intercept of 0 using linear regression t-tests.
2.4 Results
A total of 30 grizzly bear blood samples comprising 24 individuals were collected. I
excluded nine samples because three replicate measurements (asssays) were not possible
(insufficient DNA quantity or quality). Twenty-one samples corresponding to unique
individuals (14 males and seven females) ranging from 1.4 to 15.7yr of age were included
in the TRF assay (Appendix 1). Data on HCC and GGT were not available for one and
two of these individuals, respectively. For 11 samples where more than three replicate
TRF measurements were made, I selected three replicates at random for inclusion in
statistical analyses.
I ran a total of eight TRF assays. Two blots were missing a human blood sample
control and I did not discard TRF measurements from these blots because it would
compromise my sample size. Inter-assay variation based on CV in mean TRF of the
human blood control (six blots) was 17.80%. Qualitatively, grizzly bear telomere smears
had wider distributions of lengths, which appeared to be bimodal, in comparison to the
human control (Figure 1). Mean TRF length ranged from 11.75kb to 14.13kb. Based on
AIC, the most parsimonious model for mean TRF length comprised age, sex, HCC, and
GGT, and the interaction between age and sex, age and HCC, and HCC and GGT as
predictors (Appendix 2). There was no evidence for outliers, non-normality or
heteroscedasticity. There was evidence for collinearity between age and HCC and
between HCC and GGT (variance inflation factor >10; O’Brien 2007) and these terms
were removed from the model. In the final model (age, sex, HCC, GGT and the
17
interaction between age and sex), the effect of age on mean TRF was significant (Table
1). The effect of the interaction between age and sex was marginally significant. The
effect of age on mean TRF was not significant in males (r2=0.0046, F1,12=0.056, P=0.82),
but significant in females (r2=0.89, F1,5=41.51, P=0.0013; Table 2), who showed an
increase in mean TRF with age (0.21kb per year; Figure 2).
Due to small DNA quantities, I conducted two TRF assays on a small subset of
nine samples with and without BAL-31 treatment. DNA quantities were not sufficient to
allow for replicates. CV in mean TRF of the human blood control in these two assays was
0.048%. Qualitatively, southern blots of TRFs with and without BAL-31 treatment
revealed little to no visible signal for TRFs treated with BAL-31 (Figure 3; Appendix 3).
For four samples, BAL-31 treatment unexpectedly resulted in mean TRFs that were
longer than controls after averaging the two individual TRF measurements (one for each
ladder). These samples were run on the same blot and CV between the measurements was
high (mean CV across four samples=12.69%). For each ladder, mean TRF lengths of
controls were always comparably longer than BAL-31 treated samples and this
comparison was reversed when TRFs were averaged. Even with the high CV, I did not
discard this blot so that the effect of BAL-31 could be explored. Differences between
mean TRFs with and without BAL-31 treatment were marginally non-significant (paired
t-test, t=2.22, df=8, P=0.057). The relationship between mean TRF with and without
BAL-31 was significant (r2=0.94, P=1.84x10-5), with a slope (1.71±0.21) and intercept (-
9.48±3.39) that was significantly different from 1 (t=3.39, P=0.012) and 0 (t=-3.30,
P=0.013), respectively (Figure 4). DNA quantities were insufficient to increase sample
size and, without replicates, these findings are inconclusive.
18
Table 1. A general linear model for the effect of age, sex, HCC, GGT, and the interaction
between age and sex on mean TRF length in 21 grizzly bears. The effect of age was
significant and the effect of the interaction between age and sex was marginally
significant.
Term Estimate Standard error t value Probability
Intercept 12.05 0.69 17.36 7.23x10-6
Age 0.19 0.070 2.75 0.018
Sex 1.00 0.68 1.47 0.17
HCC -0.12 0.063 -1.90 0.082
GGT -0.0068 0.017 -0.40 0.70
Age*sex -0.20 0.094 -2.12 0.056
Table 2. Linear regressions for the effect of age on mean TRF length in 14 male and
seven female grizzly bears. The relationship between age and mean TRF length was not
significant in males but was significant in females.
Term Estimate Standard error t value Probability
M F M F M F M F
Intercept 12.52 11.45 0.39 0.26 32.28 44.55 4.94x10-13 1.08x10-7
Age -0.015 0.21 0.064 0.033 -0.24 6.44 0.82 0.0013
19
Figure 1. A sample TRF gel of 18 grizzly bear samples showing a sample analysis
window (red rectangle). Labels on the top of each lane correspond to sample
identification. A high molecular weight ladder is shown on the first lane from the right
(MW) with fragment lengths labeled in kilobase pairs (kb). A human blood control was
loaded on the second lane (HB). Mean TRFs across all grizzly bear samples in this work
(N=21) ranged from 11.75kb to 14.13kb.
20
Figure 2. Non-significant and significant linear regressions of age on mean TRF length
(in kilobase pairs) in 14 males and seven females, respectively. A dashed line represents
the linear regression of age on mean TRF length in males (open circles) while a solid line
represents the linear regression of age on mean TRF length in females (filled circles).
5 10 15
24
68
1012
14
Age (years)
Mea
n TR
F (k
b)
21
Figure 3. A sample gel showing little to no signal in samples with (1, 2) compared to
samples without (1a, 2a) BAL-31 exonuclease digestion. A high molecular weight ladder
is shown on the right lane alongside the samples (MW), with fragments labelled in
kilobase pairs (kb).
1 1a 2 2a MW kb
– 48.5 – 38.4 – 24.9 – 15.3
– 16.7!
– 14.1!
– 13.3!
– 7.6!– 8.1!
– 9.7!
– 10.8!
– 11.2!
– 11.8!– 12.3!
– 22.0!
– 29.0!
– 26.7!
22
Figure 4. A graph showing a significant model II regression between mean TRF length
with and without BAL-31 exonuclease digestion in nine grizzly bear samples. The slope
and intercept were significantly different from 1 and 0, respectively. A major axis
regression line (red) and 95% confidence intervals (grey lines) are shown. A dashed line
with a slope of 1 and intercept of 0 is also shown.
2.5 Discussion
Based on a small sample of 21 grizzly bears, this preliminary work suggests significant
13.0 13.2 13.4 13.6 13.8 14.0 14.2
13.0
13.5
14.0
14.5
Mean TRF with BAL-31 treatment (kb)
Mea
n TR
F of
con
trol (
kb)
MA regression
23
effects of age and marginally significant effects of the interaction between age and sex on
grizzly bear telomere length. More specifically, the effect of age on telomere length is
significant in females, but not significant in males. Indicators of acute (GGT) and chronic
(HCC) stress are not significant predictors of telomere length. Telomere lengths also
appear to be bimodal in distribution within individuals. Telomere length measurements
with and without terminal telomere digestion (isolating interstitial sequences) are not
significantly different. It is unlikely that the indices reported here could be used to
reliably estimate age or stress hormones in unknown grizzly bear samples. However, a
more comprehensive study in a larger set of samples is necessary to test this conclusion.
Any significant relationships obtained in a larger data set could be assessed for
predictability against an independent set of samples associated with known age, sex, and
concentrations of GGT and HCC (Dunshea et al. 2011, Pauli et al. 2011). This
exploratory work indicates TRF assays of wild grizzly bear blood samples are feasible
and facilitated through research collaborations with ongoing monitoring initiatives that
provide samples associated with age, sex, and stress data.
This study reveals an unexpected increase in telomere length with age in females
versus no change in males, which suggests telomere lengthening (e.g., telomerase
activity) or preservation might be occurring (de Lange et al. 2006). Longer telomeres are
expected in females versus males of the same age due to better ability to metabolize
reactive oxygen species because of the antioxidant properties of estrogen (Nawrot et al.
2004). In grizzly bears, this might occur after 5yr (Figure 2), when females are
reproductively mature (at approximately 6yr old [Ferguson and McLoughlin 2000]).
Estrogen could also mediate different telomere rates of change, which differ among sexes
in humans (Nordfjäll et al. 2005), mice (Ilmonen et al. 2008), and rats (Cherif et al.
2003). While blood telomere lengthening with age has been observed in American
redstarts (Bize et al. 2009), Leach’s storm petrels (Haussmann et al. 2003), water pythons
(Ujvari and Madsen 2009), and Pacific martens (Pauli et al. 2011), it is unknown whether
the observations reported here reflect a true pattern in grizzly bears due to small sample
size (N=7) and variation across blots; a larger study is necessary to confirm these
findings. A longitudinal study where multiple TRF measurements in recaptured
24
individuals are made could also determine if telomere attrition varies across age and sex,
and within individuals (e.g., nonlinear change over time). These models could have
important implications for individual life spans (Haussmann et al. 2003, Gomes et al.
2011, Dantzer and Fletcher 2015) as well as survivorship (Haussmann et al. 2005, Foote
et al. 2010, Heidinger et al. 2012, Barrett et al. 2013).
For grizzly bears, it is possible that telomeres will serve as a more suitable indicator
of biological (e.g., wear and tear; Plot et al. 2012, Pauliny et al. 2006) versus
chronological aging and stress. Sampling methods (e.g., darting versus culvert traps) and
frequency could also contribute to stress (Cattet et al. 2014) and, thus, impact telomeres.
Previous studies have shown that grizzly bears captured on multiple occasions were in
poorer age-specific body condition due to sampling in comparison to bears that were only
captured once (Cattet et al. 2008a). A larger set of samples could allow mixed effects
models for telomere length incorporating these random effects to be explored. Analyses
can also determine if muscle damage due to stress (Cattet et al. 2008b) can serve as an
indicator of biological senescence. The effects of oxidative stress on telomeres might also
be mediated by dietary (Jennings et al. 2000, Paul 2011), psychological (Epel et al. 2004)
and reproductive (Heidinger et al. 2012) stress, as well as social contact (Kotrschal et al.
2007). Relevant to grizzly bear conservation, telomere patterns could be linked to habitat
characteristics (Angelier et al. 2013, Mizutani et al. 2013) to predict or characterize
anthropogenic interactions leading to stress as effects on biological senescence. For
grizzly bears, pedigree data from genotyping samples (Craighead et al. 1995) could allow
for the exploration of potential effects of reproduction and heritability on telomere length
(Bakaysa et al. 2007, Njajou et al. 2007, Broer et al. 2013). Heritability might also
explain bimodal distributions of telomere length within individual grizzly bears, which
might result from hybridization between parents with disparate telomere lengths. Such
has been observed in zebrafish (Henriques et al. 2013), mice (Zhu et al. 1998, Dejager et
al. 2009) and dasyurid marsupials (Bender et al. 2012). Bimodal telomere lengths could
also be maintained through differential telomere processing in germ line cells among
sexes as a response to differences in stress exposure (Bender et al. 2012, Ingles and
Deakin 2016). Fluorescence in situ hybridization assays for telomere length can more
25
closely quantify and examine these characteristics (Bender et al. 2012, Ingles and Deakin
2016). However, these assays will require high-quality tissues that allow for cell culturing
(Wong et al. 2012).
Limited DNA quantities did not allow for multiple replicates on reliable blots for
all samples. Large samples are necessary to develop and optimize TRF assays. For
example, it is necessary to determine the species-specific range in telomere lengths
(11.75 to 14.13kb; Gomes et al. 2011) to choose appropriate ladders that span this range,
agarose gel concentrations (Kimura et al. 2010) and gel run times. My high inter-assay
variation (17.80%) suggests a substantial increase in sample size or number of replicates
for each individual will be necessary to increase precision (repeatability) across assays
(Eisenberg et al. 2015, Verhulst et al. 2015). However, my inter-assay variation uses a
subset of all blots (six of eight). Thus, it is unknown if the remaining blots would have
increased or decreased this estimate. My coefficient of variation between assays (that
occurred in different laboratories) is low relative to across-lab variation reported
elsewhere (from 10% to 69%; Martin-Ruiz et al. 2015). Within a lab, inter-assay
variation is also as high as 15.30% (Martin-Ruiz et al. 2015). Conducting TRF assays in
the same lab will likely decrease inter-assay variation. It is also possible that inadequate
digestion (e.g., presence of dark bands in the gel close to loading areas) could have
contributed to this variation. Additional optimization of TRF assays while ensuring
adequate enzymatic digestion could increase precision in TRF measurements and confirm
the relationships reported here. The use of additional enzymes can also ensure that
noncanonical telomeric sequences—that might vary in length across individuals—are
fully digested (Kimura et al. 2010). Unfortunately, logistical constraints (e.g.,
decommissioning radioactive materials permits, limited time and space available in
collaborating labs to develop nonradioactive protocols) precluded conducting multiple
assays in the same lab.
Taking into account variation across blots, my mean grizzly bear telomere length is
12.68±0.16kb and telomere length measured from a single polar bear cell culture falls
within this range (12kb; Gomes et al. 2011). This suggests my reported values and
26
technique are potentially relevant for polar bears. While differences in telomere length
measurements with and without telomere digestion are not significant, blots with
telomere digestion (targeting interstitial sequences only) reveal little to no signal,
qualitatively. These results are inconclusive due to small sample size and lack of
replicates. A posterior power analysis suggests a sample size of 300 paired comparisons
will be necessary to confirm my effect sizes (at a significant and power level of 0.05 and
0.80, respectively); including replicates will likely increase precision in TRF
measurements and reduce this number. Larger quantities of DNA collected in grizzly
bears will increase precision in telomere length estimates and confirm any effect of
interstitial sequences on telomere measurements. Alternative methods, such as
fluorescence in situ hybridization or single telomere length analysis, could more
accurately visualize and quantify interstitial telomeres in vitro (Meyne et al. 1990, Aubert
et al. 2012a, Montpetit et al. 2014), as well as examine telomere distributions among
cells or chromosomes within tissues and individuals. Previous in vitro assays in panda
bears have revealed no interstitial telomeres, but they were present in some carnivores
(e.g., leopards, ocelots, and ferret badgers [Meyne et al. 1990]). In vitro assays could also
determine differences in telomere lengths across blood cell types, which could vary in
composition throughout age (Aviv et al. 2006).
TRF assays are low throughput, time and labour intensive, and expensive for
frequent runs of large datasets (requiring seven to 10 days per assay; Kimura et al. 2010,
Nussey et al. 2014). TRF assays also require high-quality tissues that are not always easy
or logistically feasible to collect in all wild animals (Horn et al. 2010, Nussey et al.
2014). For applications in noninvasive sampling, a quantitative polymerase chain reaction
(qPCR)-based method for telomere quantification (Cawthon 2002, Cawthon 2009) will
be necessary as this method requires smaller DNA quantities and has higher throughput,
is less intensive, and is likely more practical (Cawthon 2002, Cawthon 2009, Kimura et
al. 2010; Chapter 3). This technique could also allow for comparisons across tissue types,
which could implicate which samples will be most informative for telomere assays.
As a first step to evaluating telomeres as a marker of aging and oxidative stress in
27
ursids, this work reveals validity of TRF assays for wild, frequently monitored animals.
Age, sex, and indicators of acute and chronic stress could explain variation in telomere
length in wild animals. While further development of telomere measurement assays to
minimize inter-assay variation in a larger set of samples will be required to confirm these
findings, the inclusion of additional physiological factors affecting telomere length could
provide further insight into telomere ecology.
28
2.6 Appendix
Appendix 1. Mean TRF length in 21 grizzly bears corresponding to mean TRF length,
age, sex, and measurements of stress hormones (hair cortisol concentration [HCC] and
serum gamma-glutamyltransferase [GGT]).
Sample
Mean TRF
length (kb) Sex Age (years)
HCC
(pg/mg) GGT (U/L)
G275 12.4 F 4.34 0.53 24
G278 12.55 M 6.39 1.21 30
G279 12.72 M 5.4 0.81 13
G283 12.80 M 15.71 4.67 42
G284 12.55 M 3.72 3.01 23
G285 12.56 M 2.73 2.03 19
G126 12.03 F 2.76 3.06 15
G119 12.46 F 5.78 4.11 NA
AB5299X 11.61 M 2.41 NA 10
ABNW4678 11.75 F 1.36 4.05 29
G111 14.14 F 9.44 1.19 26
G127 13.21 M 3.38 1.34 10
G128 12.45 M 2.76 0.89 27
G129 12.76 M 4.77 0.65 16
G150 12.56 M 2.45 0.33 NA
G151 11.35 M 6.46 3.53 42
G152 11.06 M 4.51 12.54 13
G260 13.66 F 11.38 0.94 46
G270 11.91 M 7.37 1.61 10
G287 14.13 M 2.4 3.48 19
G288 13.77 F 11.66 1.48 13
29
Appendix 2. Akaike Information Criterion (AIC) and difference in AIC compared to the
most parsimonious model for models of mean TRF length in 21 grizzly bears. Backwards
model selection began with age (A), sex (S), HCC, GGT, and all two-way interactions as
predictors and ended with a null (intercept-only) model. The most parsimonious model is
indicated in bold.
Model df AIC ΔAIC
A+S+HCC+GGT+A*S+A*HCC+A*GGT+S*HCC+S*GGT+
HCC*GGT
12 46.24 5.91
A+S+HCC+GGT+A*S+A*HCC+A*GGT+S*GGT+HCC*GGT 11 44.24 3.91
A+S+HCC+GGT+A*S+A*GGT+S*GGT+HCC*GGT 10 42.25 1.92
A+S+HCC+GGT+A*S+A*GGT+HCC*GGT 9 40.33 0.00
A+S+HCC+GGT+A*S+A*GGT 8 42.06 1.73
A+S+HCC+GGT+A*S 7 44.46 4.12
A+S+HCC+A*S 6 44.28 3.94
A+S+HCC 5 49.09 8.76
A+HCC 4 48.12 7.79
HCC 3 48.66 8.33
Null 2 55.36 15.03
30
Appendix 3. Mean TRF length in 9 grizzly bears corresponding to mean TRF length with
BAL-31 exonuclease treatment, digesting terminal telomere sequences.
Sample Mean TRF length of control
(kb)
Mean TRF length with
BAL-31 treatment (kb)
ABNW4678 13.12 13.23
AB5299 12.85 12.95
G129 13.39 13.45
G150 13.73 13.83
G260 14.67 14.01
G270 14.49 14.08
G280 14.66 14.08
G287 14.86 14.24
G288 14.41 14.05
31
Chapter 3
A qPCR assay of telomeres comparing tissue-3
type, age, sex, and population in polar bears
3.1 Summary
Telomeres potentially serve as a genetic marker of biological aging in response to age
and sex, as well as environmental stress. For sampling polar bears, quantitative
polymerase chain reaction (qPCR) assays of telomere length are likely more useful and
appropriate in comparison to other conventional methods, such as Southern blotting of
telomere restriction fragments. The latter methods require fresh, high-quality tissue
samples that are difficult to acquire from wild animals. Using the first telomere qPCR
assay in polar bears, I characterize differences in relative telomere length (ratio between
sample telomere and single copy gene quantities; T/S) attributable to age (cub, subadult,
and adult categories) and sex, and between populations (Baffin Bay, Davis Strait, Foxe
Basin, Lancaster Sound, and Western Hudson Bay). Analyses use 40 (10 females and 30
males) samples of heart, muscle, and skin collected from the same bears by Inuit hunters
across Nunavut during harvests in 2014. T/S ranges from 0.58 to 2.39, 0.48 to 3.19, and
0.58 to 2.37 for heart, muscle, and skin, respectively. No significant differences in T/S
occur across tissue types within individuals. Age, sex, and the interaction between age
and sex are significant predictors of telomere length in muscle, and potentially skin
samples. Significant differences occur among populations for all tissue-types; T/S in
Baffin Bay polar bears are significantly larger than T/S from Western Hudson Bay polar
bears. These results warrant further investigations involving larger sample sizes within
groups. Traditional knowledge and interpretations of biological senescence reported by
Inuit hunters could inform these results. Telomeric indices of age, sex, and population
may serve as novel, molecular tools for harvest monitoring and population management.
32
3.2 Background
Genetic-based methods of monitoring polar bear populations and their harvests continue
to hold promise for immediate conservation and management, especially in the face of
rapid climate-induced habitat changes. Across their range, polar bear populations have
been delineated and individually monitored using a combination of genetic (Paetkau et al.
1999, Peacock et al. 2015), aerial (e.g., Stapleton et al. 2014, Stapleton et al. 2016),
mark-recapture (e.g., Taylor et al. 2005, Taylor et al. 2006) and satellite telemetry (e.g.,
Taylor et al. 2001, Mauritzen et al. 2002) methods. These methods collect information on
population abundance, sex and age structure, survival, and indicators of health, which
serve to predict probabilities of decline and sustainable harvest rates (e.g., Taylor et al.
2006). In spite of these efforts, these surveys occur infrequently (Peacock et al. 2011),
and are expensive (Dowsley 2009a) and often dangerous to conduct. Comprehensive
surveys of each of Canada’s polar bear populations (Figure 5) occur once every 10 to 15
years (Peacock et al. 2011) and require three to four years to conduct, plus additional
time for data analysis and reporting (M. Dyck, Government of Nunavut, personal
communication). In addition, local communities do not always support these methods,
which has led to unique conflicts in co-management (Clark et al. 2008, Tyrell and Clark
2014). Thus, less invasive biopsy-based darting methods have been developed because
they do not require physical capture of individuals (Pagano et al. 2014) to which Inuit
object (Tyrell 2006). However, these methods still require expensive aerial support to
complete and must be coupled with genetic methods to identify (Van Coeverden de Groot
et al. 2013) and sex (Pagès et al. 2009) individuals to estimate demographic parameters.
Unpredictable field weather conditions also increase difficulty in collecting these data for
timely management applications (Government of Nunavut 2015). Molecular-based
methods of estimating age and/or inferring population health would certainly improve, if
not complement, the utility of using less invasive survey methods.
Inuit communities that harvest polar bears participate in surveys and collect data
from harvests throughout and between survey years (Dowsley 2009b, Peacock et al.
2011, Vongraven and Peacock 2011). Community Hunters and Trappers Organizations
33
and the Government of Nunavut Department of Environment gather information on the
date, location, and sex of killed bears by collecting the baculum from hunters (Brower et
al. 2002) and reporting ear tags and tattoo markings for bears that were previously
captured. The lower jaw or first premolar tooth from each harvested bear is also collected
for age determination (Calvert and Ramsay 1998). Polar bears are harvested from
populations following quotas for each population and these records are necessary to
monitor and confirm numbers, sex, and spatial distributions of bears that are harvested
(Brower et al. 2002).
Population and harvest monitoring of polar bears could benefit from telomere-based
information on biological senescence (wear-and-tear), as well as chronological aging.
Telomeres could also serve to determine environmental effects on senescence.
Environmental perturbations have been found to contribute directly to telomere
shortening (Mitzutani et al. 2013), or through effects on body fat accumulation (Hall et
al. 2004) and early growth (Watson et al. 2015). Estimations of telomere length usually
involve Southern blotting of telomere restriction fragments (TRF; Kimura et al. 2010).
However, this approach has low-throughput, is time-intensive, and for repeatability
requires high-quality samples, such as fresh and/or frozen blood samples stored at -80°C
or below (Horn et al. 2010, Kimura et al. 2010, Aubert et al. 2012b, Nussey et al. 2012).
For species where TRF assays have not been developed, such samples are critical to
ensure resulting measurements and telomere characteristics, such as distribution of
lengths, are reliable and accurately represent the species. This constraint creates logistic
challenges for the collection of tissue samples from polar bears. Such initiatives require
governmental wildlife sampling, research, and transport permits (Wong et al. 2012) and
knowledge and experience in tracking and locating individual animals across remote sea
ice environments. Further, veterinary experience in anaesthetizing is necessary, as are
handling and monitoring individual polar bears. Add to this the general lack of -80°C
and/or below storage freezers and transport materials (e.g., dry ice and/or liquid nitrogen)
in arctic communities. Even when these are available, it takes at least two days to ship
samples to laboratories (outside of Nunavut) where adequate storage conditions exist.
Such challenges are more often insurmountable than not.
34
For polar bears, an alternative method is necessary. Quantitative polymerase chain
reaction (qPCR) can quantify telomeres (Cawthon 2002, Cawthon 2009) and this method
is preferable to TRF assays because it is less sensitive to tissue degradation (Aviv et al.
2011) and requires small DNA quantities (Cawthon 2002, Cawthon 2009, Kimura et al.
2010). These attributes permit the use of noninvasively collected samples. This chapter
describes my efforts to characterize telomeres as potential monitoring tools in wild polar
bears. Using captive zoo samples, I initially developed a TRF assay to examine telomere
lengths in fresh, high-quality polar bear samples collected opportunistically during
routine veterinarian exams. Small sample sizes and time limit the approach (Appendix
3.6.1). Using a larger dataset consisting of heart, muscle, and skin samples collected from
wild, harvested polar bears across Nunavut, I used a qPCR assay to examine the effects of
age, sex, and population on telomere length. I also compared telomere lengths derived
from qPCR and TRF assays using a small number of grizzly bears.
35
Figure 5. A map showing distributions of Nunavut communities among 16 of 19 global
polar bear populations (Laptev, Kara, and Barents Sea populations not shown). EG=East
Greenland, AB=Arctic Basin, CS=Chukchi Sea, SB=Southern Beaufort, NB=Northern
Beaufort Sea, VM=Viscount Melville, NW=Norwegian Bay, KB=Kane Basin,
LS=Lancaster Sound, BB=Baffin Bay, MC=M’Clintock Channel, GB=Gulf of Boothia,
FB=Foxe Basin, WH=Western Hudson Bay, SH=Southern Hudson Bay, and DS=Davis
Strait. Map reproduced by the Department of Environment, Government of Nunavut.
3.3 Methods
3.3.1 QPCR in samples of wild polar bears
Through research agreements with the Government of Nunavut Department of
Environment, I assembled a database of 368 (166 muscle, 86 heart, and 116 hair attached
to skin) polar bear samples from 192 harvested bears (132 males and 60 females) in 2014.
36
For each sample, the local hunter and/or conservation officer visually sexed and aged the
bear according to “adult”, “subadult”, “2 year old cub”, “one year old cub”, and “cub of
year” categories based on body size and teeth eruption. I combined the latter three age
categories into a single “cub” category to allow for multiple young bears to be included in
subsequent comparisons. Samples were stored in local community freezers until transport
to the Department of Environment, Government of Nunavut in Igloolik. Upon receipt,
samples were stored at -20°C and subsequently shipped to Ottawa in coolers with ice
packs. I picked the samples up and transported them to the Royal Ontario Museum for
storage at -80°C in the Laboratory of Molecular Systematics. As samples were fairly
large in size (ranging from 5cm3 to 10cm3), I subsampled 1cm3 from the center of each
tissue to facilitate archiving, identification, and retrieval of samples and to avoid tissue
damage owing to repeated freeze-thaw.
I isolated genomic DNA from the tissue samples using a standard salt extraction
method (Bruford et al. 1992) and ran DNA samples out on 1% (w/v) agarose gels to
examine DNA quality. I quantified all samples using a Nanodrop spectrophotometer
(University of Toronto, M. Sokolowski Lab). TRF assays could not be completed on
these samples due to insufficient DNA quality; some evidence for degradation appeared
on agarose gels and this would have impacted measurements of telomere length (Kimura
et al. 2010). Because qPCR targets short fragments, it was presumed to be less sensitive
to degradation (Aviv et al. 2011). Though qPCR might be unable to discount interstitial
telomeric repeats (Haussman and Mauck 2008, Monaghan 2010), I assumed interstitial
sequences in all individuals would be of the same length and, thus, would have had
negligible effects on telomere length estimation.
Because this study was exploratory, I selected a subset of 120 samples (40
muscle, heart, and skin from the same individuals) for telomere qPCR instead of the
entire database. Samples were chosen on the basis of highest quality and quantity and
allowing for intra-individual tissue comparisons (heart, muscle, and skin from the same
individual). The University of Guelph Agriculture and Food Laboratory Service (S.
Chen) analyzed these tissues, using primers and protocols that I recommended to them
37
(Cawthon 2002, Cawthon 2009). Telomere primers were previously published: telg (5’-
ACACTAAGGTTTGGGTTTGGGTTTGGGTTTGGGTTAGTGT-3’) and telc (5’-
TGTTAGGTATCCCTATCCCTATCCCTATCCCTATCCCTAACA-3’), producing an
amplicon size of 79bp (Cawthon 2009). I chose RPLP0 in polar bears (accession
XM_008707681) as a single copy reference gene following previous telomere qPCR
assays in mice (Callicott and Womack 2006), humans (Hewakapuge et al. 2008,
O’Callaghan et al. 2011), cetaceans (Olsen et al. 2012) and carnivores (Pacific marten;
Pauli et al. 2011). Reference primers were designed using Primer Express® Software
(Applied Biosystems) synthesized using an ABI 3900 HT DNA synthesizer (Applied
Biosystems): RPLP0-F1 (5’-AATGCTTCATTGTGGGAGCA-3’) and RPLP0-R1 (5-
TCATGGTGTTCTTGCCCATC-5’), producing an amplicon of 105bp.
I initially tested telomere primers (telc/telg [Cawthon 2009]) and developed a
combination of RPLP0 primers using conventional polymerase chain reaction (PCR). I
designed RPLP0 primers using AmplifX 1.5.4 and optimized them by varying annealing
temperatures in PCR and sequencing amplicons using ABI BigDyeTM Terminator v3.1
(Heiner et al. 1998) on an ABI 3130 (Applied Biosystems) to confirm primer specificity.
I performed all PCRs on an Eppendorf AG 5345 thermal cycler and ran reaction products
out on 1.5% agarose gels to confirm amplicon sizes. Each 25µL PCR reaction contained
10mM dNTP, 10µM of each primer, 1xPCR buffer (1.5mM MgCl2; Fisherbrand), 0.75U
of Taq DNA polymerase (New England Bioilabs Inc.), and 15–20ng of DNA. Cycling
conditions were as follows: 94°C for 2min, followed by 40 cycles of 94°C for 30s,
annealing for 45s, and 72°C for 45s, with a final extension at 72°C for 7min. Annealing
temperatures were 62°C and 54–62°C for telomere and reference primers, respectively. I
conducted initial qPCR trials (University of Toronto, J. Mitchell and M. Sokolowski
Labs) using telomere and resulting RPLP0 primers to examine melt curves for primer
specificity (Ririe et al. 1997). However, to increase objectivity and minimize time and
financial costs required to develop and optimize qPCR, I commissioned the University of
Guelph Agriculture and Food Laboratory Service (S. Chen) for their technical expertise
in primer design and general qPCR optimization to analyze my data set.
38
Singleplex qPCR amplifications were carried out on a PCR MicroAmpTM Fast 96-
well Reaction plate sealed with MicroAmpTM Optical Adhesive Film (Applied
Biosystems). Samples were run in triplicate along with a serial dilution of a standard
(100.00, 20.00, 4.00, 0.80, and 0.16ng per reaction) run in duplicate on each plate. This
standard comprised DNA isolated from liver sampled from a deceased captive neonate
polar bear at the Toronto Zoo. Each 25µL reaction contained: 1xSYBR Green PCR
master mix (Invitrogen), 0.7mM MgCl2, 400nM of each primer, 0.6U AmpliTaq Gold
DNA polymerase (Applied Biosystems), 1x Q-solution (Qiagen; for telg and telc
reactions only), and 20–30ng of genomic DNA. Amplifications were conducted using
7500 Fast Real-Time PCR (Applied Biosystems). For each reaction, singleplex
amplifications were carried out at the same time (e.g., two plates, one for telc/g and one
for RPLP0) on two qPCR machines using the same well position. Cycling conditions for
telg/telc were 15min at 95°, 2 cycles of 15s at 94°C, 15s at 49°C, 32 cycles of 15s at
94°C, and 30s at 62°C with signal acquisition. Cycling conditions for RPLP0 primers
were 10min at 95°C, 32 cycles of 20s at 95°C, and 30s at 60°C with signal acquisition.
Upon completion, amplification signals were acquired using the 7500 software v.2.01
(Applied Biosystems) and reported as baseline corrected Ct values (versus correction
using LinRegPCR [Ruitjer et al. 2009], which could result in variation in efficiencies
across dilutions [Olsen et al. 2012]). Two non-template controls were run on each plate to
detect contamination and melt curves for the first 30 samples were examined to confirm
primer specificity (Ririe et al. 1997).
Mean Ct values for each sample and standard dilution (three and two technical
replicates, respectively) were used to calculate telomere to single copy gene quantities
(T/S). I calculated qPCR efficiency for each plate by running a linear regression to
generate a standard curve (the effect of log concentration on Ct) and using the equation
10-1/slope –1, where a value of 1 indicates 100% efficiency (Pffafl 2001). Because
efficiency differed between plates for each singleplex reaction, I determined T/S using
the equation 10(b-Ct)/a for telomere and reference quantities, where b and a referred to
intercept and slope, respectively, of the corresponding standard curve (Pffafl 2001, Olsen
et al. 2012).
39
To determine assay repeatability, I calculated mean standard deviation of Ct
values (versus coefficients of variation [CV] in Ct values, which are inherently lower
[Bustin et al. 2009]) for telomere and reference primers across technical replicates (Olsen
et al. 2012) for each heart, muscle, and skin data set. To determine assay reproducibility,
I calculated mean standard deviations in Ct for each standard dilution sample across
plates. Heart, muscle, and skin samples could not be used because technical replicates for
these samples were made on the same plate. To calculate overall telomere and reference
qPCR efficiency, I calculated mean r2 and mean efficiency across plates. To standardize
and calculate means of standard deviations and efficiencies, I z-transformed values,
calculated the mean of z-transformed values, and then back-transformed the calculated
mean. Similarly, to calculate mean r2, I transformed r2 to Fisher’s z’ (normal
distribution), calculated the mean of z’-transformed values, and back-transformed the
calculated mean (Clayton and William 1987).
All statistical procedures were performed in R. To determine biological variability
in T/S across individuals, I determined CV for heart, muscle, and skin data sets. To
determine differences in T/S across tissues, I compared T/S in heart versus muscle, heart
versus skin, and muscle versus skin using major axis model II regressions (lmodel2
package in R; Sokal and Rohlf 1969, Legendre and Legendre 1998). I tested for
significant differences from slopes and intercepts of 1 and 0, respectively, using linear
regression t-tests. I also conducted paired t-tests (Appendix 5). Using plots, I examined
the data set for outliers and model assumptions (normality, constant error variance
[homoscedasticity], and collinearity) to determine if transformations were necessary.
Slopes and intercepts were reported as values ± standard error.
For each set of heart, muscle, and skin samples, the effect of age, sex, population,
and interactions between age and sex on T/S was determined using type III sums of
squares in a multi-factor ANOVA (car package in R; Hector et al. 2010). To find the
most parsimonious model (model that best explained variation in T/S), I began with a full
model (age, sex, population, and the interactions between age and sex) and eliminated
non-significant variables using backward selection and F tests (drop1 function in R),
40
finishing with the null (intercept only) model. I selected the model structure with the
lowest Akaike Information Criterion as the most parsimonious model (Hurvich and Tsai
1989, Burnham and Anderson 2004). The resulting model was examined for outliers,
normality, and homoscedasticity (constant error variance), as well as collinearity.
Significant effects were further examined using post-hoc Tukey’s Honest Significant
Difference (HSD) tests (agricolae package in R, for unbalanced sample sizes). Due to
small sample sizes within groups that limit the ability to detect violations of model
assumptions, nonparametric Kruskal-Wallis rank sum tests were also used to detect
significant differences among groups.
I did not test for the effect of sex and population interactions because there were
no females from one population (Davis Strait) sampled for my data set. For the same
reason, I did not test the effect of age and population interactions, as there were no
samples for some age and population combinations. Due to small degrees of freedom
(N≤7 provided by most communities), I examined differences in T/S among communities
qualitatively using boxplots.
3.3.2 Comparisons between TRF and qPCR assays
In the absence of polar bear samples that allowed for TRF assays to be conducted (e.g.,
high-quality samples from captive polar bears at zoos), TRF and qPCR assays were
compared in the same set of grizzly bear blood samples with sufficient DNA quantities
for these analyses. Methods for grizzly bear blood sampling and DNA isolation were
described in Chapter 2. Quantitative PCR of grizzly bear samples followed the same
primers and procedures as above and were run on a single plate (for each telomere and
reference primer set) with polar bear samples. The relationship between mean TRF length
and T/S was tested using a standard major axis model II regression (Sokal and Rohlf
1969, Legendre and Legendre 1998) and t-tests for significant differences in slope and
intercept from 1 and 0, respectively. Values were reported as means ± standard error. As
in Chapter 2, I also determined if the effect of age, sex, and indicators of acute (serum
gamma-glutamyltransferase) and chronic (hair cortisol concentration) stress on grizzly
41
bear telomere length was significant, using blood T/S (Appendix 3.6.3).
3.4 Results
3.4.1 Telomeres in harvested polar bears based on qPCR
From the full database of salvaged samples, a subset of the highest quality DNA from
120 (40 each of muscle, heart, and skin) tissues from 40 individuals (10 females and 30
males) was selected for qPCR analysis (Appendix 11). These samples comprised 29
adults, six sub-adults, and four cubs across Baffin Bay (N=10), Davis Strait (N=6), Foxe
Basin (N=5), Lancaster Sound (N=8), and Western Hudson Bay (N=10) populations.
Samples were collected during harvests by Arctic Bay (N=7), Arviat (N=7), Clyde River
(N=3), Hall Beach (N=1), Iqaluit (N=6), Igloolik (N=4), Grise Ford (N=2), Pond Inlet
(N=7), and Rank Inlet (N=3) communities (Figure 5). Age was not available for tissues
collected from a single male in Lancaster Sound by Arctic Bay.
Twelve qPCR plates (six plates for each primer) were run for the 120 samples
(Appendix 12 to 17). Melt curves for seven sample dilutions ranging from 0.0064 to 10ng
per reaction in duplicate (14 reactions) confirmed specificity of telomere and reference
primers; a single peak for melting temperatures occurred for each primer set (Ririe et al.
1997; Appendix 18 and 19). Two samples produced Ct values that fell outside the
standard range and, thus, were re-run; one sample was diluted 10X before the second run
and the other was increased in concentration (by making a smaller dilution from the
original sample). There was no evidence of contamination, as Ct values for non-template
controls were either not detected or exceeded the highest Ct value for the other samples
by at least five cycles. For the 40 individuals, mean standard deviations of telomere Ct
across technical replicates were 0.24, 0.27, and 0.13 for heart, muscle, and skin data sets,
respectively. Mean standard deviations of reference Ct were 0.16, 0.27, and 0.11 for
heart, muscle, and skin, respectively. Using the five sample-dilutions replicated on each
plate, mean standard deviation of Ct across the six plates was 0.51 and 0.27 for telomere
and reference primers, respectively. Mean r2 across plates was 1.00 and 1.00 for telomere
42
and reference primers, respectively (Appendix 20). Mean efficiency across plates was
0.85 and 1.02 for telomere and reference primers, respectively.
Across individuals, T/S ranged from 0.58 to 2.39, 0.48 to 3.19, and 0.58 to 2.37 in
heart, muscle, and skin, respectively. CV in T/S was 0.33, 0.41, and 0.36 in heart, muscle,
and skin, respectively. One outlier in the muscle data set was removed (T/S of 23.20
standard deviations from the mean of the other values) resulting in 40 T/S observations
for heart and skin and 39 T/S observations for muscle in the analyzed data set. The
relationship between heart and muscle T/S was significant (r2=0.27, P=6.53x10-4); the
slope (0.67±0.20) and intercept (0.39±0.25) were not significantly different from 1 (t=-
1.69, P=0.099) and 0 (t=1.52, P=0.14), respectively (Figure 6). The relationship between
heart and skin T/S was significant (r2=0.21, P=0.0032); the slope (0.95±0.37) and
intercept (0.13±0.44) were not significantly different from 1 (t=-0.13, P=0.90) and 0
(t=0.29, P=0.77), respectively (Figure 7). The relationship between muscle and skin T/S
was significant (r2=0.13, P=0.026); the slope (1.67±1.57) and intercept (-0.68±1.85) were
not significantly different from 1 (t=0.43, P=0.67) and 0 (t=-0.37, P=0.72), respectively
(Figure 8). For all three models, there was no evidence for outliers, non-normality, or
heteroscedasticity.
For heart T/S, population was the only predictor in the most parsimonious model
(Appendix 21). One outlier was detected falling outside 95% confidence intervals in the
quantile-quantile plot fitted for normality. This outlier did not affect subsequent analyses
(Appendix 6). There was no evidence for non-normality, heteroscedasticity, or
collinearity. The effect of population on heart T/S was significant (Table 3). A Kruskal-
Wallis test also confirmed significant differences in heart T/S across populations
(χ2=18.62, df=4, P=9.33x10-4). A post-hoc Tukey’s HSD test indicated heart T/S in
Western Hudson Bay was significantly shorter than Baffin Bay and Foxe Basin
populations (Figure 9).
For muscle T/S, the full model (age, sex, population, and the interaction between
age and sex) was the most parsimonious model (Appendix 22). Two outliers fell outside
43
the 95% confidence interval on the quantile-quantile plot; one outlier was clearly evident
through a plot for Cook’s distance. This outlier did not affect subsequent analyses
(Appendix 7). There was no evidence for non-normality or heteroscedasticity. The effect
of all predictors (age, sex, population and the interaction between age and sex) on muscle
T/S were significant (Table 4). ANOVAs examining differences among age groups in
males and females did not detect any significant differences (Table 5; Figure 10), likely
due to lack of statistical power (small N within groups). A post-hoc Tukey’s HSD test
indicated muscle T/S in Western Hudson Bay was significantly shorter than Baffin Bay
and Lancaster Sound (Figure 11). Kruskal-Wallis tests did not detect significant
differences in muscle T/S across age groups in males (N=30; χ2=2.98, df=2, P=0.23) and
females (N=10, χ2=3.33, df=2, P=0.19), as well as across populations (χ2=8.93, df=4,
P=0.063), likely due to lower statistical power in this test and testing for these terms
alone.
For skin T/S, the full model was also the most parsimonious model (Appendix
23). One outlier fell within the 95% confidence interval in the quantile-quantile plot and
was, thus, not removed. There was no evidence for non-normality, homoscedasticity, or
collinearity. The effect of population on skin T/S was significant; all other terms in the
model were not significant (Table 6). A Kruskal-Wallis test confirmed significant
differences among populations (χ2=16.57, df=4, P=0.0023). A post-hoc Tukey’s HSD test
indicated skin T/S in Western Hudson Bay was significantly shorter than Baffin Bay and
Davis Strait populations (Figure 12).
Based on boxplots and qualitative interpretations, heart, muscle, skin T/S, varied
across communities in a relatively consistent manner (Figure 13). Longer T/S were
associated Clyde River and Pond Inlet communities, while shorter T/S were associated
with Arviat and Rankin Inlet.
44
Figure 6. A graph of a significant model II regression between heart and muscle T/S in 39
polar bears. The slope and intercept were not significantly different from 1 and 0,
respectively. A major axis regression line (red) and 95% confidence intervals (grey lines)
are shown. A dashed line with a slope of 1 and intercept of 0 is also shown.
0.5 1.0 1.5 2.0 2.5 3.0
0.5
1.0
1.5
2.0
2.5
3.0
Muscle T/S
Hea
rt T/
S
MA regression
45
Figure 7. A graph of a significant model II regression between heart and skin T/S in 40
polar bears. The slope and intercept were not significantly different from 1 and 0,
respectively. A major axis regression line (red) and 95% confidence intervals (grey lines)
are shown. A dashed line with a slope of 1 and intercept of 0 is also shown.
1.0 1.5 2.0
1.0
1.5
2.0
Skin T/S
Hea
rt T/
S
MA regression
46
Figure 8. A graph of a significant model II regression between muscle and skin T/S in 39
polar bears. The slope and intercept were not significantly different from 1 and 0,
respectively. A major axis regression line (red) and 95% confidence intervals (grey lines)
are shown. A dashed line with a slope of 1 and intercept of 0 is also shown.
0.5 1.0 1.5 2.0 2.5 3.0
0.5
1.0
1.5
2.0
2.5
3.0
Skin T/S
Mus
cle
T/S
MA regression
47
Table 3. A one-way analysis of variance using type III sums of squares showing
significant differences in heart T/S among Baffin Bay (N=10), Davis Strait (N=6), Foxe
Basin (N=5), Lancaster Sound (N=9), and Western Hudson Bay (N=10) polar bear
populations.
Factor Type III sums of
squares
df F value Probability
Population 2.95 4 6.55 4.81x10-4
Residuals 3.94 35
48
Figure 9. A graph showing significant differences in heart T/S across polar bear
populations. BB=Baffin Bay, FB=Foxe Basin, DS=Davis Strait, LS=Lancaster Sound,
and WHB=Western Hudson Bay. Letters represent significant groupings based on post-
hoc multiple comparisons.
BB FB DS LS WH
0.0
0.5
1.0
1.5
2.0
2.5
Population
Hea
rt T/
S
a a a b a b b
49
Table 4. A multi-factor analysis of variance using type III sums of squares showing
significant effects of age, sex, population, and the interaction between age and sex on
muscle T/S in 39 polar bears.
Factor Type III sums of
squares
df F value Probability
Age 2.94 2 15.87 2.47x10-5
Sex 4.67 1 50.50 9.87x10-8
Population 3.94 4 10.63 2.28x10-5
Age*sex 3.90 2 21.051 2.63x10-6
Residuals 2.59 28
Table 5. One-way analyses of variance using type III sums of squares showing non-
significant differences in muscle T/S among age groups in 29 male and 10 female polar
bears.
Factor Type III sums of
squares
df F value Probability
M F M F M F M F
Age 0.37 2.59 2 2 1.68 2.38 0.21 0.16
Residuals 2.73 3.80 25 7 - - - -
50
Figure 10. A box plot comparing muscle T/S among age groups in 10 females (F) and 30
males (M).
0.5
1.0
1.5
2.0
2.5
3.0
Cub Subadult Adult Cub Subadult Adult
F M
Mus
cle
T/S
51
Figure 11. A graph showing significant differences in muscle T/S across polar bear
populations. BB=Baffin Bay, LS=Lancaster Sound, DS=Davis Strait, FB=Foxe Basin,
and WH=Western Hudson Bay. Letters represent significant groupings based on post-hoc
multiple comparisons.
BB LS DS FB WH
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
Population
Mus
cle
T/S
a a a b a b b
52
Table 6. A multi-factor analysis of variance using type III sums of squares showing non-
significant effects of age, sex, and the interaction between age and sex and a significant
effect of population on skin T/S in 40 polar bears.
Factor Type III sums of
squares
df F value Probability
Age 0.48 2 2.55 0.095
Sex 0.26 1 2.82 0.10
Population 2.41 4 6.42 7.93x10-4
Age x sex 0.48 2 2.55 0.096
Residuals 2.72 29
53
Figure 11. A graph showing significant differences in muscle T/S across polar bear
populations. BB=Baffin Bay, DS=Davis Strait, LS=Lancaster Sound, FB=Foxe Basin,
and WH=Western Hudson Bay. Letters represent significant groupings based on post-hoc
multiple comparisons.
BB DS LS FB WH
0.0
0.5
1.0
1.5
2.0
2.5
Population
Ski
n T/
Sa a b a b c b c c
54
Figure 12. A qualitative comparison of heart, muscle, and skin T/S across communities.
AB=Arctic Bay (N=7), AR=Arviat (N=7), CR=Clyde River (N=3), GF=Grise Ford
(N=2), HB=Hall Beach (N=1), IG=Igloolik (N=4), IQ=Iqaluit (N=6), PI=Pond Inlet (N=7
for heart and skin, N=6 for muscle) and RI=Rankin Inlet (N=3).
AB AR CR GF HB IG IQ PI RI
1.0
1.5
2.0
Community
Hea
rt T/
S
AB AR CR GF HB IG IQ PI RI
0.5
1.0
1.5
2.0
2.5
3.0
Community
Mus
cle
T/S
AB AR CR GF HB IG IQ PI RI
1.0
1.5
2.0
Community
Ski
n T/
S
55
3.4.2 Comparisons between TRFs and T/S
Fourteen grizzly bear blood samples allowed for mean TRF and blood T/S comparisons
to be made (Appendix 3.6.3). Mean standard deviation of Ct across three technical
replicates was 0.13 and 0.050 for telomere and reference primers, respectively.
Quantitative PCR efficiency was 0.78 and 0.97 for telomere and reference, primers,
respectively. Coefficients of determination (r2) for standard curves were 1.00 and 1.00 for
telomere and reference primers, respectively. Across grizzly bears, blood T/S ranged
from 0.69 to 1.01. CV of blood T/S across individuals was 0.094. The relationship
between blood T/S and mean TRF length was not significant (r2=2.23x10-6, P=1.00). The
slope (-0.099±0.032) and intercept (-5.65±0.40) differed significantly from 1 (t=-34.61,
P<1.0x10-4) and differed marginally non-significantly from 0 (t=5.28, P=2.0x10-4),
respectively (Figure 14).
56
Figure 13. A graph of a non-significant model II regression between mean TRF length
and blood T/S measured in 14 grizzly bears. The slope and intercept were significantly
different from 1 and marginally significantly different from 0, respectively. A standard
major axis regression line (red) and 95% confidence intervals (grey lines) are shown.
3.5 Discussion
In this study, telomere lengths do not differ across heart, muscle, and skin tissues within
40 individual polar bears. Analyses of muscle and skin samples reveal potential effects of
age, sex, and the interaction between age and sex on telomere length. These effects are
only significant in muscle samples. Analyses of all three tissues reveal significant
11.0 11.5 12.0 12.5 13.0 13.5 14.0
0.70
0.75
0.80
0.85
0.90
0.95
1.00
Mean TRF length (kb)
Blo
od T
/S
SMA regression
57
differences across Baffin Bay, Davis Strait, Foxe Basin, Lancaster Sound, and Western
Hudson Bay populations, with longer telomere lengths in Baffin Bay versus Western
Hudson Bay. Small sample sizes preclude the ability to further examine differences in
telomere length across age groups in males and females, and across communities. Using
grizzly bear samples, no relationship exists between telomere lengths reported in TRF
and qPCR assays. However, my results suggest qPCR can distinguish telomere lengths in
tissues salvaged from harvested polar bears that vary with age, sex, and population.
Despite differences in replicative potential (Friedrich et al. 2000, de Lange et al.
2006), range in telomere length is similar across heart, muscle, and skin. While age and
sex do not explain variation in telomere length in heart tissues, they do so in muscle and
potentially skin samples from harvested bears. It is possible that age is an important
predictor of telomere length in muscle and skin, due to higher proliferation rates of these
tissues in comparison to heart (Friedrich et al. 2000, de Lange et al. 2006). However,
only muscle samples show a significant effect of age and sex on telomere length.
Unfortunately, small sample sizes within age and sex groups (cub, subadult, and adult
N=2, 3, and 5, respectively for females and N=2, 3, and 25, respectively, for males) do
not allow for meaningful comparisons among female and male age groups. Based on
qualitative observations (Figure 10), adult females might have longer telomeres than
adult males due to estrogen levels that mediate shortening due to oxidative damage
(Nawrot et al. 2004), as I observed in grizzly bears (Chapter 2). Increasing sample sizes
within age and sex groups in the same population can further explore these findings.
Posterior power analyses suggests a minimum of 5 males and 4 females in each age group
will be necessary (for significant and power levels of 0.05 and 0.80, respectively, in
groups of equal sample size) to confirm my effect sizes. Indices describing relationships
between age and telomere length could be developed by including continuous age-
estimates derived from premolar tooth growth patterns in harvested bears (Calvert and
Ramsay 1998), which will be available for my dataset in 2017. Increasing sample sizes in
skin samples will also increase statistical power to confirm and/or determine age and sex
effects, which have important implications for the utility of biopsy-based population
surveys (Pagano et al. 2014). Obtaining larger samples of genomic material across age
58
and sex groups are also relatively easier to achieve through noninvasive tissue sampling
(for the M’Clintock Channel population; van Coeverden de Groot et al. 2013) and
telomere assays of such samples will have direct implications for noninvasive surveys. It
is also likely that DNA quality and quantity and, thus, estimates and resulting indices of
telomere length will be improved with the use of commercially available kits (e.g.,
QIAGEN DNeasy Blood and Tissue Kit; QIAGEN 69506), versus the salt extraction
protocol used here. If relationships are significant, telomeres can be used to potentially
predict age and/or sex groupings of harvested and/or noninvasively sampled polar bears.
This will require evaluating accuracy in classifying an independent sample of known
samples according to T/S characteristics (Dunshea et al. 2011, Pauli et al. 2011). For
noninvasive samples, known individuals can be identified by sampling and genotyping
previously captured and aged bears (van Coeverden de Groot et al. 2013).
Given small sample sizes and additional factors contributing to variation in
telomere length, telomere qPCR of tissue samples reported here will likely not serve to
accurately determine the chronological ages of polar bears. Notwithstanding, my results
provide insights into additional factors that affect telomere length as an indicator of
biological senescence. Even with small within-group sample sizes, significant differences
in telomere lengths exist among populations in three types of tissues. Significantly longer
telomere lengths occur in polar bears from Baffin Bay versus Western Hudson Bay. In
muscle, post-hoc comparisons among populations correspond to ecologically-defined
designated units for conservation, where Western Hudson Bay, Foxe Basin, and Davis
Strait form one cluster and Baffin Bay and Lancaster Sound form another (Thiemann et
al. 2008a). Western Hudson Bay is also associated with lower prey diversity than the
other four populations, though, interestingly, a lower hunting pressure index (Thiemann
et al. 2008a). Differences in muscle telomere length also correspond to differences in
heterozygosity, with lower rates in Western Hudson Bay versus Baffin Bay and Lancaster
Sound and intermediate rates in Davis Strait and Foxe Basin (Peacock et al. 2015). Lower
heterozygosity rates might limit telomere lengthening from homologous recombination
(de Lange et al. 2006, Blasco 2007). Higher reproductive and growth rates in Western
Hudson Bay compared to the other populations (Derocher and Stirling 1998) could also
59
be contributing to higher rates of cellular turnover and, thus, shorter telomere lengths.
Globally, Western Hudson Bay is the most extensively researched polar bear
population (e.g., Taylor and Lee 1995, Lunn et al. 1997, Regehr et al. 2007). Over 80%
of the population has been marked in the past (Peacock et al. 2011, Vongraven and
Peacock 2011). This population, as well as Davis Strait, faces an annual ice-free season,
where bears must fast ashore for at least four months and eight months for denning
females (Ramsay and Stirling 1988, Stirling and Parkinson 2006). With earlier sea-ice
break up due to climate change, significant relationships with declining body condition
have been reported (Stirling et al. 1999, Regehr et al. 2007), particularly in females
(Stirling and Parkinson 2006), who also show evidence for reproductive failure (Derocher
et al. 1992). Western Hudson Bay bears have also been reported entering communities as
rogue or problem bears (Stirling and Parkinson 2006, Dowsley 2009a; Chapters 4 and 5),
facing unique stressors in comparison to other populations. Conversely, for Baffin Bay,
Inuit communities have reported population increases due to immigration from Lancaster
Sound (Dowsley 2007).
If larger sample sizes distinguish populations, telomeres may serve to implicate
unique population-specific stressors that individuals might be facing; this has important
implications for managing quotas. At a minimum, qPCR of tissues from harvested
samples can provide useful information on age, sex, and population-level differences in
telomere length. Harvested samples can also be coupled with genetic indices of
relatedness or heterozygosity of larger population groups (Cronin et al. 2009, Zeyl et al.
2009) to quantify their effects on telomere length. It is also possible to include indices of
stress and/or health, such as hair cortisol (Beschøft et al. 2011), contaminants measured
from body fat (Verreault et al. 2005), body size, and condition (Rode et al. 2010).
Ecological observations of Inuit hunters collecting samples (e.g., traditional knowledge of
bear health and condition) can also enrich this information. Determining hunter
selectivity (Chapter 4) associated with harvest samples can provide inferences on whether
telomere patterns are generalizable to polar bear populations as a whole. Increasing
sample sizes among communities can also confirm differences in telomere length that
60
correspond geographically to populations, or potential differences in hunting selection
across communities. With more comprehensive studies, population differences in
telomere length can be evaluated for predictability in an independent sample of harvested
bears.
Despite the potential utility of qPCR in polar bears, telomere lengths determined
using qPCR and TRF in grizzly bears are not comparable. This is likely an artefact of
small sample size and high coefficient of variation in the TRF assays (17.80%; Chapter
2), as qualitative trends between telomere length and age are still comparable (e.g.,
unexpected increase in telomere length with age in females versus no change in males;
Appendix 3.6.3). While TRF assays have been referred to as the “gold standard” for
telomere length measurements, this technique will have little applicability or feasibility
for polar bear monitoring programs. It is unknown how sensitive qPCR is to varying
degrees of tissue degradation that might be expected from harvest sampling across
communities. The effect of tissue and/or DNA degradation and different storage methods
(Wong et al. 2012) could certainly be explored. Obtaining a range of high quality and
quantities of genomic material is difficult in polar bears because most invasive samples
are dependent on harvest-based sampling by hunters. Where freezing below conventional
deep freezer or ambient freezing temperatures are not available, quality of salvaged polar
bear tissues might be improved with alternative methods such as storing samples in
DNAgard (Wong et al. 2012). It is unknown how effective these chemicals are at high-
arctic temperatures (e.g., freezing during travel to sampling sites), and effects of freezing
on storage quality could be evaluated prior to field sampling. Isolating DNA from
samples immediately or as soon as possible after collection can also improve sample
quality (Wong et al. 2012), for example, at research centers in larger communities. DNA
extractions could be conducted with relative ease using non-toxic salt extraction methods
(Bruford et al. 1992). However, this would require substantial funding to operate
facilities, engage communities, and educate hunters to coordinate sampling and storage
according to standards (Wong et al. 2012). For polar bears, TRF assays could still be
developed in captive animals, but this would require long-term collaborations with zoos
to acquire adequate sample sizes that vary in age and sex, and population and/or origin, as
61
sampling usually occurs on an opportunistic basis. Assays in captive polar bears would
also likely be the most practical opportunity for longitudinal studies. Still, it is unknown
how applicable or useful telomere indices found in captive animals will be for wild
animals without comparisons.
In initiating efforts to characterize telomeres across different age, sex, and
population groups of polar bears, this work demonstrates the utility of qPCR in detecting
differences in telomere length using heart, muscle, and skin tissues salvaged from
harvested animals. While significant differences in telomere length across polar bear
populations could reflect local genetic and ecological stressors, differences among age
groups and sex require further investigations using larger sample sizes. With the inclusion
of additional scientific data on life-history and ecological observations provided by
hunters, a more comprehensive evaluation of telomeres as a marker of biological
senescence across polar bear populations will be enabled.
62
3.6 Appendix
3.6.1 Development of a TRF assay of captive (zoo) polar bear
samples
Samples for TRF assays were collected through individual research agreements with
Toronto Metro, Albuquerque Biopark, Cleveland Metroparks, Brookfield, Buffalo, North
Carolina, SeaWorld (San Diego), and San Diego zoos and the U.S. Fish and Wildlife
Service to transport samples. After research agreements were established, I distributed
instructions for sampling, storage, and transport (10mL of fresh blood collected into
vacutainers with EDTA, stored at -80°C, transported via FedEx Priority Overnight on dry
ice) to each zoo. Samples were previously or opportunistically collected during routine
exams by zoo veterinarians and shipped to the University of Texas Southwestern Medical
Center. For each sample, I distributed sample information sheets to each institution to
collect information on sex and age of the originating specimen, specimen numbers,
birthplace and/or length in captivity, any previous zoo (holding) locations, past health
conditions of concern, and purpose of anaesthesia or exam during which the sample was
collected. I processed and analyzed samples at the University of Texas Southwestern
Medical Center (Shay/Wright Lab) over three weeks in July 2013.
I isolated, visualized, quantified, and aliquoted DNA samples using methods
described in Chapter 2. TRF assays followed a modified protocol described by Herbert et
al. (2003). These procedures differed from TRF assays conducted in grizzly bears
(Chapter 2) due to differences in local laboratory TRF protocols and availability of
samples, materials, and/or equipment. Briefly, samples were digested with six enzymes
(HinfI, HaeIII, AluI, RsaI, MspI and HhaI) instead of two (RsaI and HinfI) and run out on
0.7% (w/v) agarose gels. I ran TRFs on a single gel that was denatured prior to in-gel
hybridization to a radioactive telomere repeat probe, which reduces background noise in
comparison to Southern blot hybridization (Herbert et al. 2003).
A total of 14 blood and eight DNA samples were collected opportunistically from
63
18 captive polar bears. Nineteen samples (14 individuals) provided sufficient DNA
quantities for TRFs (at least 2µg per assay), as several preliminary trials were required to
develop the technique. Due to limited time and funding available to process and complete
these optimizations abroad, only one gel (Appendix 4) was completed. TRF distributions
fell beyond the ladder range (10kb to 0.50kb; Bionexus Hi-LoTM DNA marker) and, thus,
could not be quantified (Horn et al. 2010). Without a control (sample of known TRF
range) or replicate assays, results from these trials are inconclusive.
64
Appendix 4. A TRF gel of polar bears samples provided by zoos. Samples are labeled at
the top of each lane, as well as a negative control (NEG). Two grizzly bear samples
(GB16274 and GB16273) were included for comparison. AK741 and AL063 produced
no signal. PB9769, PB5579, AK732, AK731, AK734, and M0211A produced weak
signals. A high molecular weight ladder is shown on the right lane alongside the samples
(MW), with fragments labelled in kilobase pairs (kb).
65
3.6.2 Supplementary analyses
Appendix 5. Results from non-significant paired t-tests comparing T/S among polar bear
heart, muscle, and skin tissues (N=40, 39, and 40 individuals, respectively).
Comparison t value df Probability
Heart and muscle -0.60 38 0.55
Heart and skin 1.02 39 0.31
Muscle and skin 1.29 38 0.21
Appendix 6. A one-way analysis of variance using type III sums of squares showing the
significant effect of population on heart T/S in 39 polar bears (one outlier was excluded
from the original sample of 40).
Predictor Type III sums of
squares
df F value Probability
Population 2.88 4 9.011 4.50x10-5
Residuals 2.71 34
66
Appendix 7. A multi-factor analysis of variance using type III sums of squares showing
significant effects of age, sex, population, and the interaction between age and sex on
muscle T/S in 38 polar bears (one outlier was excluded from the original sample of 39).
Predictor Type III sums of
squares
df F value Probability
Intercept 17.31 1 196.55 6.53x10-14
Age 3.13 2 17.76 1.20x10-5
Sex 4.49 1 51.018 1.11x10-7
Population 4.14 4 11.76 1.16x10-5
Age*sex 4.066 2 23.078 1.43x10-6
Residuals 2.38 27
67
3.6.3 Age, sex, and stress effects on grizzly bear telomere length
using qPCR
QPCR was conducted for 17 grizzly bear blood samples (from nine males and eight
females) that provided enough DNA for this analysis. Fourteen of these samples were
associated with TRF measurements (see text). Using the model for telomere length that I
developed with TRF assays (Chapter 2), I determined the effect of age, sex, HCC, and
GGT, and the interaction between age and sex on blood T/S using an ordinary least
squares linear regression. I examined the data set for outliers and model assumptions
(normality, constant error variance [homoscedasticity], and collinearity). I also
determined the effect of age on blood T/S separately in males and females through linear
regression. Significant levels were set at an alpha (P) of 0.05.
Blood T/S ranged from 0.69 to 1.015 (Appendix 8). Effects of age, sex, HCC,
GGT, and the interaction between age and sex on blood T/S were not significant
(Appendix 9). There was no evidence for outliers, departures from normality,
heteroscedasticity, or collinearity. The effect of age on blood T/S was not significant in
nine males (r2=2.35x10-7, F1,7=1.65x10-6, P=1.00) and eight females (r2=0.0056,
F1,6=0.034, P=0.86). Qualitatively, the relationship between age and telomere length
using qPCR (blood T/S) in males and females followed a similar trend to that using TRF
assays (mean TRF; Appendix 10, Figure 2).
68
Appendix 8. Blood T/S measured from qPCR and mean TRF length (in kilobase pairs)
measured from TRF assays in 17 grizzly bear samples (nine males and eight females).
“NA” refers to data that were not available.
Sample Blood T/S Mean TRF (kb)
AB5299X 1.01 11.61
ABNW4678 0.77 11.75
G016 0.78 NA
G119A 0.77 12.57
G120 0.81 NA
G126 0.95 12.03
G129 0.80 12.76
G150 0.69 12.56
G151 0.75 11.35
G152 0.92 11.06
G260 0.89 13.66
G270 0.87 11.91
G275 0.85 12.40
G278 0.92 12.55
G280 0.76 NA
G287 0.85 14.13
G288 0.94 13.77
69
Appendix 9. A general linear model for the effect of age, sex, HCC, GGT, and the
interaction between age and sex on blood T/S in 17 grizzly bears. Effects were not
significant.
Term Estimate Standard error t value Probability
Intercept 0.87 0.073 12.01 2.13x10-6
Age 5.99x10-4 0.0052 0.12 0.91
Sex -0.067 0.12 -0.56 0.59
HCC 0.0063 0.0080 0.79 0.46
GGT -0.0012 0.0011 -1.063 0.32
Age*sex 0.0070 0.020 0.36 0.73
70
Appendix 10. A graph showing non-significant linear regressions between blood T/S and
age in 17 grizzly bears. Trends are similar to relationships using TRF assays (Chapter 2,
Figure 2). A dashed line represents the linear regression between blood T/S and age in
nine males (open circles) while a solid line represents the linear regression between blood
T/S and age in eight females (filled circles).
0 5 10 15 20
0.70
0.75
0.80
0.85
0.90
0.95
1.00
Age (years)
Blo
od T
/S
71
3.6.4 QPCR data and standard curves for six telomere and
reference primer plates
Appendix 11. Polar bear samples collected by Inuit hunters for qPCR corresponding to
community that provided the sample, population where the sample was harvested, age,
and sex diagnoses. DS=Davis Strait, WHB=Western Hudson Bay, LS=Lancaster Sound,
FB=Foxe Basin, and BB=Baffin Bay. “NA” refers to a single case where age data was
not available. Heart, muscle, and skin samples were collected from each individual.
Sample Community Population Age Sex
L39002 Iqaluit DS Adult Male
L39014 Iqaluit DS Adult Male
L39019 Arviat WHB Adult Male
L39020 Rankin Inlet WHB Adult Male
L39021 Arviat WHB Subadult Female
L39022 Arviat WHB Subadult Female
L39023 Arviat WHB Adult Male
L39024 Arviat WHB Adult Male
L39025 Arviat WHB Adult Male
L39027 Arviat WHB Cub Female
L39044 Rankin Inlet WHB Subadult Male
L39046 Rankin Inlet WHB Adult Male
L39056 Iqaluit DS Subadult Male
L39058 Iqaluit DS Adult Male
L39206 Grise Ford LS Adult Male
L39211 Grise Ford LS Adult Male
L39212 Iqaluit DS Adult Male
L39214 Iqaluit DS Adult Male
L39220 Igloolik FB Cub Male
L39223 Igloolik FB Cub Male
L39224 Igloolik FB Cub Female
L39231 Hall Beach FB Adult Female
72
L39254 Igloolik FB Adult Female
L39258 Arctic Bay LS Adult Male
L39260 Arctic Bay LS Adult Female
L39262 Arctic Bay LS Adult Male
L39266 Arctic Bay LS NA Male
L39267 Arctic Bay LS Adult Female
L39271 Arctic Bay LS Subadult Male
L39278 Arctic Bay LS Adult Male
L39283 Clyde River BB Adult Male
L39291 Clyde River BB Subadult Female
L39294 Clyde River BB Adult Male
L39307 Pond Inlet BB Adult Male
L39310 Pond Inlet BB Adult Male
L39313 Pond Inlet BB Adult Male
L39314 Pond Inlet BB Adult Male
L39316 Pond Inlet BB Adult Male
L39325 Pond Inlet BB Adult Female
L39326 Pond Inlet BB Adult Male
73
Appendix 12. Cycle threshold values (Ct) for Plate 1 of 6 telomere (telc/telg) and
reference (RPLP0-F1/RPLP0-R1) qPCR assays. Telomere and reference primers were
run in singleplex; both plates were run at the same time on separate machines. Samples
were run in triplicate while five standard dilutions (Z19312D) were run in duplicate.
Sample identification ending in “HG”, “MG”, and “SG” denote heart, muscle, and skin
samples, respectively.
Sample Telomere Ct Reference Ct
L39002HG 15.41 22.71
15.23 22.66
15.13 22.62
L39002MG 15.14 22.71
15.08 22.68
15.15 22.60
L39002SG 16.31 23.77
16.31 23.79
16.29 23.67
L39014HG 14.55 22.67
14.62 22.56
14.62 22.56
L39014MG 15.18 21.64
15.11 22.47
15.27 23.02
L39014SG 14.12 22.35
14.03 22.26
14.08 22.30
L39019HG 15.22 22.94
15.33 23.16
15.29 23.22
L39019MG 14.93 24.13
16.00 23.94
74
15.90 24.07
L39019SG 14.42 22.77
14.62 22.69
14.64 22.78
L39020HG 13.69 22.21
13.88 22.23
13.92 22.21
L39020MG 16.27 23.46
16.29 24.00
16.47 24.20
L39020SG 14.13 22.34
14.19 22.43
14.23 22.43
L39021HG 13.84 20.70
14.05 22.18
14.14 22.17
L39021MG 12.97 22.72
14.45 22.75
14.73 22.90
L39021SG 14.04 22.52
14.12 22.57
14.24 22.50
L39022HG 15.04 22.93
15.20 23.04
15.24 22.97
L39022MG 16.56 24.28
16.50 24.19
16.53 24.06
L39022SG 13.78 22.04
13.95 21.99
13.89 22.05
75
L39023HG 15.54 23.04
15.44 23.10
15.37 23.10
L39023MG 14.81 23.32
15.33 23.39
15.46 23.39
L39023SG 14.19 22.28
14.16 22.29
14.09 22.26
L39024HG 14.93 23.58
15.61 23.50
15.71 23.38
L39024MG 16.34 23.95
16.17 23.96
16.31 23.31
L39024SG 14.22 22.50
14.55 22.53
14.51 22.51
L39025HG 15.39 23.29
14.57 23.40
15.39 23.38
L39025MG 15.60 23.38
15.38 23.52
15.14 23.46
L39025SG 14.79 22.12
14.74 22.98
14.91 23.11
L39027HG 14.45 21.64
14.32 22.32
14.49 22.42
Z19312D - 0.16ng/reaction 23.90 31.11
76
23.84 31.23
Z19312D - 0.80ng/reaction 21.25 28.84
21.21 28.68
Z19312D - 4.00ng/reaction 18.65 26.37
18.61 26.70
Z19312D - 20.00ng/reaction 15.84 23.85
15.91 23.95
Z19312D - 100.00ng/reaction 12.86 21.68
12.96 21.76
77
Appendix 13. Cycle threshold values (Ct) for Plate 2 of 6 telomere (telc/telg) and
reference (RPLP0-F1/RPLP0-R1) qPCR assays. Telomere and reference primers were
run in singleplex; both plates were run at the same time on separate machines. Samples
were run in triplicate while five standard dilutions (Z19312D) were run in duplicate.
Sample identification ending in “HG”, “MG”, and “SG” denote heart, muscle, and skin
samples, respectively.
Sample Telomere Ct Reference Ct
L39044HG 14.54 23.48
15.57 23.53
16.27 23.60
L39044MG 16.62 23.70
16.09 23.97
16.81 24.34
L39044SG 17.43 26.18
17.41 25.72
17.56 25.97
L39046HG 16.94 25.26
16.01 25.38
16.88 25.35
L39046MG 15.44 23.92
15.69 23.99
15.68 23.91
L39046SG 15.76 23.47
15.19 23.67
15.39 23.58
L39056HG 14.72 22.89
14.57 22.75
14.74 22.63
L39056MG 15.63 23.37
15.23 23.57
78
15.63 23.58
L39056SG 15.45 23.68
16.22 23.77
15.95 23.47
L39058HG 16.26 24.30
16.16 24.43
16.56 24.31
L39058MG 15.22 23.63
15.43 23.81
15.69 23.75
L39058SG 14.37 22.94
14.44 22.98
14.81 22.99
L39206HG 14.38 23.00
14.07 22.93
14.76 22.94
L39206MG 16.36 24.97
16.73 25.04
16.68 25.08
L39206SG 13.98 22.71
14.27 22.83
14.32 22.61
L39211HG* 13.80 20.34
14.60 21.23
13.93 20.90
L39211MG 16.53 24.39
16.43 24.03
16.42 23.99
L39211SG 14.68 22.88
14.40 22.80
14.33 22.85
79
L39212HG 14.82 22.64
14.48 22.57
14.35 22.57
L39212MG 14.03 23.35
15.33 23.42
15.21 23.33
L39212SG 15.14 23.28
14.96 23.47
14.90 23.12
L39214HG 15.23 23.48
15.25 23.37
15.67 23.42
L39214MG 16.46 25.10
17.43 24.98
17.31 24.94
L39214SG 15.19 22.73
15.05 22.58
14.78 22.61
L39220HG 14.92 22.76
14.54 22.83
14.68 22.65
L39220MG 15.09 23.14
14.82 22.58
15.02 23.23
L39220SG 14.65 23.23
14.27 23.27
14.54 23.28
L39223HG 13.96 23.10
14.22 23.13
14.20 23.06
Z19312D - 0.16ng/reaction 22.43 29.19
80
22.42 29.30
Z19312D - 0.80ng/reaction 20.33 28.39
20.11 28.50
Z19312D - 4.00ng/reaction 17.97 26.05
19.06 26.36
Z19312D - 20.00ng/reaction 15.17 23.79
15.53 23.79
Z19312D - 100.00ng/reaction 12.81 21.78
13.04 21.80 * Ct values for this sample fell outside the standard range; this sample was diluted 10X
and re-run on Plate 6.
81
Appendix 14. Cycle threshold values (Ct) for Plate 3 of 6 telomere (telc/telg) and
reference (RPLP0-F1/RPLP0-R1) qPCR assays. Telomere and reference primers were
run in singleplex; both plates were run at the same time on separate machines. Samples
were run in triplicate while five standard dilutions (Z19312D) were run in duplicate.
Sample identification ending in “HG”, “MG”, and “SG” denote heart, muscle, and skin
samples, respectively.
Sample Telomere Ct Reference Ct
L39223MG 15.37 23.61
15.19 23.74
15.34 23.66
L39223SG 14.55 22.71
14.40 22.74
14.62 22.89
L39224HG 15.09 23.36
14.63 23.26
14.95 23.27
L39224MG 15.17 23.61
14.98 23.67
15.09 23.71
L39224SG 13.63 22.65
13.49 22.64
13.45 22.71
L39231HG 14.97 23.13
14.59 23.10
14.79 23.05
L39231MG 15.80 23.94
15.81 23.92
15.80 23.96
L39231SG 16.75 25.04
16.43 25.05
82
16.48 25.05
L39254HG 15.03 22.95
15.63 22.04
15.37 22.71
L39254MG 14.63 23.27
15.43 23.72
15.58 23.51
L39254SG 13.86 22.46
13.95 22.42
14.21 22.37
L39258HG 13.65 23.06
14.82 22.95
14.98 22.94
L39258MG 14.90 23.58
15.45 23.54
15.17 23.48
L39258SG 13.98 22.90
13.91 22.95
14.13 22.96
L39260HG 14.65 22.95
14.84 22.96
14.88 22.83
L39260MG 16.14 23.94
16.25 22.83
16.34 24.02
L39260SG 14.42 22.27
14.47 22.27
14.28 22.26
L39262HG 15.36 23.06
15.67 23.04
15.60 23.13
83
L39262MG 15.77 24.32
16.38 23.94
16.08 24.15
L39262SG* 25.20 36.66
25.25 35.68
25.29 36.57
L39266HG 14.25 22.50
14.27 22.41
14.05 22.53
L39266MG 13.94 23.92
15.99 23.83
15.72 23.98
L39266SG 16.25 22.40
16.01 23.68
16.08 23.83
L39267HG 15.65 23.19
15.52 23.26
15.08 23.16
L39267MG 16.16 22.22
16.13 23.86
16.41 23.77
L39267SG 13.72 22.17
13.55 22.30
13.86 22.26
L39271HG 14.19 22.84
14.26 22.90
14.48 22.63
L39271MG 14.89 22.36
14.82 23.44
14.97 23.40
Z19312D - 0.16ng/reaction 22.63 30.58
84
22.54 30.68
Z19312D - 0.80ng/reaction 20.17 28.47
19.97 28.31
Z19312D - 4.00ng/reaction 18.21 26.13
18.70 27.66
Z19312D - 20.00ng/reaction 15.70 23.79
15.91 23.86
Z19312D - 100.00ng/reaction 12.66 21.77
13.29 21.65 * Ct values for this sample fell outside the standard range; this sample re-run on Plate 6
using a lower dilution (more concentrated sample).
85
Appendix 15. Cycle threshold values (Ct) for Plate 4 of 6 telomere (telc/telg) and
reference (RPLP0-F1/RPLP0-R1) qPCR assays. Telomere and reference primers were
run in singleplex; both plates were run at the same time on separate machines. Samples
were run in triplicate while five standard dilutions (Z19312D) were run in duplicate.
Sample identification ending in “HG”, “MG”, and “SG” denote heart, muscle, and skin
samples, respectively.
Sample Telomere Ct Reference Ct
L39271SG 14.99 22.59
13.95 22.47
13.92 22.53
L39278HG 18.79 26.92
18.31 26.78
18.79 26.70
L39278MG 16.38 23.80
16.32 24.01
16.40 24.09
L39278SG 14.88 23.02
14.90 22.95
14.90 23.04
L39283HG 15.68 23.09
15.70 23.36
15.75 23.49
L39283MG 16.94 24.65
16.93 24.59
16.96 24.47
L39283SG 14.34 22.74
14.35 22.70
14.42 22.67
L39291HG 14.92 22.96
14.91 23.08
86
14.94 22.93
L39291MG 14.98 23.06
15.23 23.12
15.03 23.22
L39291SG 14.39 22.91
14.38 22.92
14.38 22.89
L39294HG 14.39 22.92
15.07 22.96
15.05 22.57
L39294MG 15.29 23.29
14.41 23.39
14.91 23.48
L39294SG 15.47 23.60
15.55 23.56
15.57 23.58
L39307HG 14.92 22.88
15.04 23.06
15.14 22.99
L39307MG 16.25 23.48
15.93 24.17
15.25 22.99
L39307SG 13.85 22.06
13.99 21.92
13.97 21.81
L39310HG 17.44 24.08
16.50 24.98
16.98 25.06
L39310MG 17.84 25.24
17.75 25.29
17.70 25.23
87
L39310SG 15.38 23.18
15.21 23.26
15.33 23.26
L39313HG 16.06 23.84
15.97 24.00
15.70 24.01
L39313MG 14.81 22.94
15.98 23.77
14.93 23.38
L39313SG 15.98 24.07
15.85 24.04
15.86 24.06
L39314HG 16.43 24.09
16.06 23.95
16.03 23.92
L39314MG 15.94 20.95
15.47 19.28
15.24 21.50
L39314SG 15.51 23.58
15.56 23.79
15.56 23.59
L39316HG 16.75 24.42
16.60 24.47
16.61 24.52
L39316MG 18.25 25.53
17.77 26.09
17.19 26.04
L39316SG 16.34 24.21
16.35 24.33
16.45 24.28
Z19312D - 0.16ng/reaction 23.16 30.59
88
23.15 30.54
Z19312D - 0.80ng/reaction 20.57 28.44
20.58 28.37
Z19312D - 4.00ng/reaction 18.16 26.04
17.96 26.13
Z19312D - 20.00ng/reaction 14.92 23.68
15.42 23.91
Z19312D - 100.00ng/reaction 12.94 21.80
13.08 21.78
89
Appendix 16. Cycle threshold values (Ct) for Plate 5 of 6 telomere (telc/telg) and
reference (RPLP0-F1/RPLP0-R1) qPCR assays. Telomere and reference primers were
run in singleplex; both plates were run at the same time on separate machines. Samples
were run in triplicate while five standard dilutions (Z19312D) were run in duplicate.
Sample identification ending in “HG”, “MG”, and “SG” denote heart, muscle, and skin
samples, respectively.
Sample Telomere Ct Reference Ct
L39027MG 16.94 24.30
16.54 24.19
16.76 24.64
L39027SG 14.26 22.65
14.28 22.56
14.19 22.60
L39325HG 15.18 23.52
15.66 22.11
15.67 23.23
L39325MG 15.78 23.22
14.88 21.01
16.00 22.92
L39325SG 14.57 22.42
14.43 22.31
14.54 22.34
L39326HG 15.29 23.67
15.63 23.47
15.67 22.97
L39326MG 16.25 24.38
16.42 24.31
16.43 24.11
L39326SG 14.81 22.23
14.33 22.70
90
14.33 22.39
Z19312D - 0.16ng/reaction 24.43 30.91
24.41 30.96
Z19312D - 0.80ng/reaction 21.61 28.69
21.56 28.93
Z19312D - 4.00ng/reaction 18.73 26.25
18.60 26.39
Z19312D - 20.00ng/reaction 15.83 23.67
13.62 23.80
Z19312D - 100.00ng/reaction 12.92 21.65
12.55 21.80
91
Appendix 17. Cycle threshold values (Ct) for Plate 6 of 6 telomere (telc/telg) and
reference (RPLP0-F1/RPLP0-R1) qPCR assays. Telomere and reference primers were
run in singleplex; both plates were run at the same time on separate machines. Samples
were run in triplicate while five standard dilutions (Z19312D) were run in duplicate. This
plate included grizzly bear samples as well as two polar bear samples (L39211HG [heart]
and L39262SG [skin]).
Sample Telomere Ct Reference Ct
G275 16.29 24.52
16.51 24.53
16.27 24.50
G278 15.74 24.15
16.08 24.13
16.34 24.13
G126 16.21 24.39
16.30 24.29
16.44 24.25
G119A 15.95 24.33
15.98 24.26
15.93 24.33
G016 15.83 24.16
15.93 24.43
15.83 24.09
G120 16.47 24.52
16.14 24.56
16.00 24.26
ABNW4678 16.87 25.09
16.67 25.02
16.69 24.85
AB5299X 15.74 23.24
14.84 23.18
92
14.74 23.11
G288 15.78 24.06
16.09 23.96
15.92 23.97
G287 15.87 23.94
15.63 24.01
15.74 24.04
G280 15.71 24.19
15.83 24.20
15.88 24.20
G270 15.81 24.06
15.95 24.12
15.95 24.11
G260 15.68 24.07
15.86 24.03
16.12 24.03
G152 15.74 23.86
15.89 23.97
15.87 24.00
G151 15.28 23.87
15.54 23.94
15.55 23.95
G150 15.57 24.26
15.61 24.19
15.71 24.16
G129 15.90 24.21
15.93 24.22
15.98 24.28
L39211HG* 18.72 24.96
18.23 25.63
18.29 25.77
93
L39262SG* 14.35 21.17
14.12 22.17
14.29 22.56
Z19312D - 0.16ng/reaction 24.43 31.52
24.45 31.08
Z19312D - 0.80ng/reaction 21.74 28.92
21.55 28.44
Z19312D - 4.00ng/reaction 18.82 26.55
18.78 26.36
Z19312D - 20.00ng/reaction 16.13 23.92
16.21 23.91
Z19312D - 100.00ng/reaction 13.38 21.88
13.20 21.66
* Samples were run a second time after producing Ct values that fell outside the standard
range on the first attempt.
94
Appendix 18. Melt curves for seven dilutions ranging from 0.0064 to 10ng per reaction in
duplicate (14 reactions) showing a single peak, confirming specificity of telomere
(telc/telg) primers.
95
96
Appendix 19. Melt curves for seven dilutions ranging from 0.0064 to 10ng per reaction in
duplicate (14 reactions) generally showing a single peak, confirming specificity of
reference (RPLP0-F1/RPLP0-R1) primers.
97
Appendix 20. Characteristics of standard curves six telomere (telc/g) and reference
(RPLP0 [F1/R1]) qPCR plates. For each plate and primer, standard curves were
generated through a log-linear regression of five standard dilutions (0.16ng, 0.80ng,
4.00ng, 20.00ng, and 100.00ng per reaction) as predictors of mean threshold cycle
number for fluorescence detection (Ct).
Plate Slope Intercept r2 Efficiency
telc/g RPLP0 telc/g RPLP0 telc/g RPLP0 telc/g RPLP0
1 -3.90 -3.99 20.85 28.47 1.00 1.00 0.80 0.78
2 -3.42 -2.78 19.94 27.58 0.99 0.98 0.96 1.29
3 -3.36 -3.21 20.00 28.22 0.99 0.99 0.98 1.05
4 -3.67 -3.17 20.20 28.04 1.00 1.00 0.87 1.07
5 -4.33 -3.37 21.03 28.33 0.99 1.00 0.70 0.98
6 -3.97 -3.41 21.26 28.48 1.00 1.00 0.78 0.97
3.6.5 Model selection for telomere length
Appendix 21. Akaike Information Criterion (AIC) and difference in AIC compared to the
most parsimonious model (ΔAIC) for models of heart T/S in 40 polar bears. Backwards
model selection began with age, sex, population, and the interaction between age and sex
as predictors and ended with a null (intercept-only) model. The most parsimonious model
is indicated in bold.
Model df AIC ΔAIC
Age + sex + population + age*sex 13 37.81 4.97
Age + population + age*sex 12 36.01 3.17
Age + population 8 34.67 1.83
Population 6 32.84 0.00
Null 2 47.19 14.35
98
Appendix 22. Akaike Information Criterion (AIC) and difference in AIC compared to the
most parsimonious model (ΔAIC) for models of muscle T/S in 39 polar bears. Backwards
model selection began with age, sex, population, and the interaction between age and sex
as predictors and ended with a null (intercept-only) model. The most parsimonious model
is indicated in bold.
Model df AIC ΔAIC
Age + sex + population + age*sex 11 27.80 0.00
Age + sex + population 9 58.68 30.87
Sex + population 7 58.05 30.25
Sex 3 62.11 34.31
Null 2 63.56 35.76
Appendix 23. Akaike Information Criterion (AIC) and difference in AIC compared to the
most parsimonious model (ΔAIC) for models of skin T/S in 40 polar bears. Backwards
model selection began with age, sex, population, and the interaction between age and sex
as predictors and ended with a null (intercept-only) model. The most parsimonious model
is indicated in bold.
Model df AIC ΔAIC
Age + sex + population + age*sex 11 28.81 0.00
Age + sex + population 9 31.12 2.31
Age + population 8 29.23 0.43
Population 6 38.02 9.21
Null 2 48.96 20.15
99
Chapter 4
Inuit methods of identifying polar bear 4
characteristics: potential for Inuit inclusion in
polar bear surveys
4.1 Summary
Due to their close proximity to and frequent interactions with polar bears, Inuit hunters
are aware of changes in polar bear population ecology and characteristics. This valuable
information could contribute to any polar bear research and/or monitoring program.
Understanding how Inuit gather ecological information on polar bears and how individual
experiences shape this knowledge can also overcome any barriers to Inuit inclusion in
bear monitoring and management. Based on interviews in four Nunavut communities, I
report Inuit hunting experiences and methods of identifying polar bear sex, age, and body
size, as well as health. Across communities, Inuit share techniques in identifying and
distinguishing bear characteristics that overlap with scientific methods, suggesting Inuit
could provide immediate and inexpensive information toward polar bear research
programs. Hunting preferences are shaped by individual experiences with polar bears
(e.g., through hunting or bear encounters), as well as familiarity with polar bear research
and management. Identifying and incorporating community perspectives in management
could encourage local support for programs that impact Inuit knowledge formation and
persistence.
4.2 Polar bear conservation and harvest management in
Nunavut
The need for contemporary data on polar bear population trends parallels a growing need
for management actions, which undoubtedly impacts northern communities
economically, socially, and ecologically. Inuit legally harvest polar bears (Indian and
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Northern Affairs Canada [INAC] 1993) for traditional and personal uses, including meat
for consumption, hides for clothing, bedding, and/or auctions, and bones for carving
(Foote and Wenzel 2009). Guided by Inuit using non-motorized (Inuit-based) methods
(INAC 1993), trophy hunters also harvest polar bears. This activity reinvests economic
benefits into a subsistence economy for Inuit through employment, providing wages for
guides, assistants, outfitters, dog owners, and cooks (Foote and Wenzel 2009, Tyrrell
2009, Wenzel 2009). Due to frequent interactions with polar bears and the importance of
polar bears to them, Inuit continue to gather data on ecological effects of habitat change
(Dowsley 2009a) and human activities (Keith et al. 2005) on polar bears, as well as sex,
age, and body size of bears encountered (Wong et al. 2011). This activity is independent
from scientific monitoring and management. This knowledge comprises Inuit
qaujimajatuqangit (IQ), which is defined as a guiding principle for how Inuit
conceptualize human-wildlife relationships and how this affects their interactions with
and perceptions of animals (Wenzel 2004). In this manner, Inuit could offer a nuanced,
historical and contemporary understanding of polar bear population activity to
complement ongoing scientific surveys in conservation and management.
Inuit traditional ecological knowledge (TEK)—ecological observations that are
acquired through experience and passed on from one generation to the next (Berkes et al.
2000)—is a component of IQ that is already considered in wildlife co-management and
conservation decision-making at territorial (INAC 1993) and national levels (e.g.,
Government of Canada 2002). In Canada, polar bears are managed according to 13
populations using the best available local and scientific knowledge (Peacock et al. 2011,
Vongraven and Peacock 2011). In Nunavut, territorial (Nunavut Wildlife Management
Board) and regional wildlife boards and community Hunters and Trappers Organizations
(HTO) establish harvest quotas (Tyrrell and Clark 2014) for each population, sanctioned
by land claim agreements (INAC 1993), and allocate these quotas to HTOs within
communities harvesting the same population (Dowsley 2009a, Peacock et al. 2011).
These quotas are male-biased to protect females and cubs. HTOs subsequently distribute
tags to individual hunters, usually through a lottery. HTOs also gather and represent local
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community interests to higher levels of government through community consultations
and public meetings (Dowsley 2009b, Dowsley 2010).
Scientific community-based monitoring programs and data collection ultimately
inform management decisions affecting communities (e.g., allocation of harvest quotas).
Inuit hunters frequently receive employment as guides and research assistants in polar
bear surveys (e.g., Wong et al. 2011, Van Coeverden de Groot et al. 2013), which allow
them to apply and reinforce their experience and traditional skills in research contexts.
Harvest monitoring programs, where hunters actively collect biological samples and
morphometric data from harvested bears, also allow population data (e.g., minimum
abundance, sex and age distribution, health correlates, etc.) to be collected in the years
between population surveys. Independent from research participation, Inuit TEK and
experience have the potential to reveal critical population trends (e.g, Dowsley 2009a,
Kotierk 2012, Kotierk 2010) before scientific surveys are conducted.
Unfortunately, uncertainty and the dearth of data on range-wide polar bear
responses to climate change has contributed to political tension and conflict among
stakeholders, decision-makers, scientists and northern communities (Derocher et al.
2004, Tyrrell 2006, Clark et al. 2008, Tyrrell and Clark 2014). Sustainable harvest rates
rely largely on scientifically collected population data (e.g., sex, age, and body condition;
e.g., Bromaghin et al. 2015) associated with aerial mark-recapture methods (e.g., tattoos,
radio-collars, and ear tags) that are not supported by all communities (Tyrell 2006).
Though less-invasive alternatives to gathering the same data have recently been
developed (e.g., Van Coeverden de Groot et al. 2013, Stapleton et al. 2014), scientific
surveys remain expensive (Dowsley 2009a), time-intensive, and often logistically
challenging (Stapleton et al. 2014) to conduct. Not surprisingly, scientific surveys occur
infrequently and research intensity, time scales, and techniques vary among populations
(Vongraven and Peacock 2011).
Beyond the lack of information on most polar bear populations (Peacock et al.
2011, Vongraven and Peacock 2011), criticisms against both TEK and scientific types of
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information that inform decision-making have also created challenges in and barriers to
co-management. Other nations have criticized Canada for considering TEK in decision-
making (Tyrrell and Clark 2014), perhaps due to the context-specific nature of TEK that
is actively shaped by the knowledge holder and/or gatherer (Houde 2007) and differs
from objective, conventional natural sciences. Communities across the north also criticize
decisions based on scientific practices (Tyrrell 2009), which might be due, in part, to past
misconceptions of research and management practices by local communities and failure
to address northern interests by research and management practitioners leading to
mistrust (Moller et al. 2004, Clark et al. 2008). TEK comprises only a small component
of IQ that, while containing information on the biophysical environment that could be
integrated into conventional management and policy with relative ease, lacks the breadth
of cultural, ethical and ontological approaches to managing and interacting with wildlife
that IQ encompasses as a whole (Wenzel 2004). Incorporating these elements of IQ into
any research program could overcome some of these barriers.
At local scales, supporting the role played by Inuit in polar bear monitoring
programs can increase understanding of TEK and/or IQ and scientific information by
Inuit and scientific communities alike, while addressing gaps in population data. In these
contexts, documenting Inuit methods of and motivations for identifying polar bear
characteristics can highlight Inuit methods of characterizing population information at a
level finer than broad trends in abundance and, more importantly, IQ of Inuit
relationships with polar bears. IQ influences decision-making through co-management
yet, through impacts on harvesting opportunities, management decisions could also affect
the persistence of IQ. An understanding of how management regulations direct and
influence the process of Inuit knowledge formation can provide insights into receptivity
and levels of local support for those management decisions. For Inuit, documenting Inuit
methods can also safeguard IQ for future generations for Inuit.
Expanding on previous interviews with Gjoa Haven hunters (Wong et al. 2011), I
report on interviews with 23 hunters and 33 elders (48 men and 8 women) that range in
their participation in hunting, research, and management activities. Interviews occur
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across Nunavut in Gjoa Haven, Arctic Bay, Arviat and Kimmirut. Dialogues point to
cultural factors and regulations that shape hunting selection and the context through
which polar bear knowledge is gathered, providing insight into knowledge persistence. I
highlight Inuit hunting experiences and methods for identifying sex, age, and body size of
polar bears, as well as health to determine their potential inclusion and relevance in polar
bear monitoring and research.
4.3 Methods
Interviews built on previous assessments of consistency and accuracy in Inuit estimates
of polar bear characteristics from in situ tracks with Gjoa Haven hunters, which largely
focused on inferences from tracks and provided little information on management
perspectives and hunting preferences (Wong et al. 2011). I initiated interviews for
methods of identifying polar bear characteristics with additional Gjoa Haven hunters and
elders and a single Kugaaruk hunter. I expanded these interviews by including Arctic
Bay, Kimmirut, and Arviat communities who participate in ongoing harvest monitoring
programs in collaboration with the Government of Nunavut. Together these communities
span all three Nunavut regions (Kitikmeot, Qikiqtaaluk, and Kivalliq), covering a broad
range in community perspectives and methods and polar bear ecology (Figure 15).
Face-to-face meetings with HTOs occurred in each community to discuss research
objectives, recruitment, and wages except in Arviat, where these discussions occurred
over telephone. HTOs prescribed and led all recruitment procedures. I recruited interview
participants through a combination of key informant and snowball sampling methods
(Marshall 1996). HTOs and appointed interpreters initially recommended interview
participants and, unless they were absent from the community (e.g., out of town or out
hunting on the land), all recommended participants participated in this work. With the
exception of Kimmirut, where participants were recruited through HTO recommendation
only, I also made radio announcements for interview locations and times (based on HTO
recommendation) to provide the opportunity for all community members to participate if
they wished to do so and, thus, covered a broad range in perspectives (Marshall 1996).
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Initial interview participants recommended additional, experienced community members
until I recruited a maximum of 20 participants from each community (based on budget
constraints) or data became saturated (no new themes emerged).
I identified participants as elders (60 years old or older and recognized for his/her
experience on the land among other community members) and hunters (less than 60 years
old and usually less experienced than elders). I also categorized participants according to
hunting experience: active hunters, non-active hunters (who have hunted but no longer do
so [e.g., elders]), and less-experienced hunters, who have assisted community members
with hunts and would hunt upon receiving a tag. To protect confidentiality and assist
readers in linking themes and quotations to each community, I coded participant names
according to their home community (Gjoa Haven [GH], Arctic Bay [AB], Kimmirut [K]
and Arviat [AR]) and the order of interview; I interviewed one Kugaaruk hunter in Gjoa
Haven (KU).
I conducted semi-structured interviews with open-ended questions following a
guideline (Huntington 2000, Table 7). Follow-up questions were intended to encourage
participants to produce their own understanding and clarify our discussions (Huntington
1998). Interviews began with direct icebreaker questions (e.g., name, age, birthplace)
followed by discussions on methods for identifying polar bear sex, age, and body size.
Additional discussions on identifying health of polar bears occurred in Arctic Bay,
Kimmirut, and Arviat. To determine context and motivation for learning these methods, I
documented participant interactions with polar bears (e.g., through hunting, guiding sport
hunts, encounters while hunting other animals) and preferences for particular bear
characteristics when hunting.
Though I covered most anticipated topics (following the guideline), additional
relevant topics were raised by some participants, such as how to identify aggressive or
dangerous bears (usually reported by Arviat participants), personal encounters with polar
bears, and discussions over hunting and identification techniques unique to some
participants. I did not probe for these unique experiences when participants did not
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mention these topics themselves to ensure participants led discussions according to their
own knowledge. Accordingly, if a participant did not mention a particular observation,
perspective, or theme it did not necessarily mean that they had (or lacked) knowledge or
experience on the subject (e.g., they simply did not mention it), unless they explicitly
indicated so.
I used an audio recorder to allow for subsequent transcribing. I recorded all
nonverbal cues, verbal styles, and relevant information that were informally shared in a
journal along with personal reflections. I analyzed interviews following conventional
content analysis, where categories, themes, and coding names were allowed to emerge
from the data without any preexisting theory (Hsieh and Shannon 2005). I summarized
unique participant perspectives, original quotations, and information that best-described
common themes and categories that arose through discussions.
Communities varied in local harvest regulations, seasons, and constraints, as well
as access to technology (Ford et al. 2006). Participant age, interpretations, recollections,
and sensitivity to topics were also shown to influence individual knowledge and
responses (Huntington 2000, Gagnon and Berteaux 2009). Together these contexts
shaped participant responses and interpretations. Hence, data validation by re-visiting,
reporting back to and engaging with HTOs constituted a critical form of peer review
(Huntington 2004) to ensure participants were accurately represented. Follow-up
meetings with HTOs occurred to clarify my interpretations and discuss preliminary
results, while allowing representative community members to incorporate additional
information that they felt was important and relevant. This additional effort revealed
community-wide hunting perspectives and concerns.
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Figure 14. A map displaying Gjoa Haven (1), Kugaaruk (2), Arctic Bay (3), Kimmirut
(4), and Arviat (5) communities where participants were interviewed for this study. Only
one participant from Kugaaruk was interviewed; this interview took place in Gjoa Haven.
Communities span Kitikmeot, Qikiqtaaluk, and Kivalliq regions in Nunavut, Canada.
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Table 7. Interview guideline.
Topic Questions
Directed introductory questions What is your name?
How old are you?
Where were you born?
How long have you lived in this
community?
Hunting experience
Have you ever hunted a polar bear before?
How many?
Why do you hunt?
How did you learn how to hunt?
How many bears have you hunted by
yourself? With other hunters?
Do you still hunt?
Where do you go to hunt bears?
Hunting preferences
When you hunt bears, are you picky/
choosey? Why?
Do you prefer to hunt males or females?
Why?
Do you prefer to hunt old or young bears?
Why?
Do you prefer big or small bears? Why?
Identifying bears Can you tell differences between bears?
How?
Can you tell if a bear is a male or female?
How?
Can you tell ages of bears? How?
Can you tell sizes of bears? How
Can you determine sex/ age/ size of a bear
from footprints? How?
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Can you tell if a bear is healthy? How?
Are bears close/ nearby your community?
Have you noticed any changes in polar
bears? What are the changes?
Experience with polar bear research
How are polar bears monitored?
Do you know why polar bears are
monitored?
What do you know about scientific
methods?
Have you ever participated on a polar bear
survey?
Have you ever collected scientific samples?
Do you know what the samples are used
for?
What do you think we need to know in
monitoring polar bear populations?
In monitoring bears, do you think polar
bear sex/ age/ size is important? Why?
What is the best way to survey polar bears?
4.4 Results
From May 2011 to April 2014 over five visits (and a follow-up visit in February 2015), I
interviewed 23 hunters and 33 elders (48 men and 8 women) individually (Table 8).
Interviews ranged from six to 63 minutes in duration and took place on the land (for GH
hunters and KU) or at participant homes, hotels, and HTO offices. Interpreters translated
34 interviews. Participants ranged from 27 to 82 years old and comprised 33 active, 14
non-active, and 9 less-experienced hunters, including at least 21 participants who had
previously guided sport hunts. Five participants from Gjoa Haven had previously
participated in noninvasive polar bear surveys and sampling (Wong et al. 2011, Van
Coeverden de Groot et al. 2013). Arctic Bay participants included an individual who was
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experienced in identifying bear characteristics through her experience in hide preparation
and sales across Nunavut (AB14). One Arctic Bay participant was a previous wildlife
officer who was experienced with polar bear surveys and sampling (AB15). Arviat
participants included two local bear patrols (AR1, who had also previously participated
on polar bear surveys, and AR2), regional wildlife (AR3) and HTO (AR20) board
members, and previous wildlife (AR15) and assistant wildlife (AR8) officers. Due to
frequent daily encounters with bears in the fall, most Arviat residents were able to
identify or at least comment on how to identify polar bear characteristics.
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Table 8. Number of interview participants from Gjoa Haven, Arctic Bay, Kimmirut, and
Arviat corresponding to participant type, hunting experience, and having mentioned
experience guiding sport hunts during interviews. Participants were categorized as elders
and hunters according to hunting experience: active hunters, non-active hunters, and less-
experienced hunters. A total of 48 men and 8 women were interviewed.
Community
Gjoa Haven* Arctic Bay Kimmirut Arviat
Participant type
Hunters 3 5 5 10
Elders 7 10 6 9
Hunting experience
Active 5 9 8 10
Non-active 5 4 1 4
Less-
experienced
0 2 2 5
Previously
guided sport
hunts
5
5
3
8
* Includes a single participant from Kugaaruk.
4.4.1 Hunter preference for bear characteristics
Across all communities, active hunters and elders were more selective than less
experienced hunters for bear characteristics. Whether a hunter was selective or not during
a hunt partially depended on logistical constraints, such as the number of bears (or tracks)
that are encountered during pursuit and time available for harvest (48hr in most
communities), while considering the amount of fuel and supplies taken to the field.
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We go by machines now…if he has enough gas…he’ll see a track. If it’s small,
he’ll look for a bigger one…but if he doesn’t have enough gas, thinking that he
won’t come back…he’ll get the first tracks. (Interpreter translating for AB12)
If I don’t get my bear in 48 hours, and I lose my tag and—and I’m out of the
hunt…the guy behind me will get a chance… sometimes you don’t really
concentrate, trying to see all the—whether it’s a male, female, how old, and you
[are] really concentrating on getting that bear and after you get your bear you
finally see what kind of bear you shot and sometimes you can tell. (AR1)
When asked if participants prefer to hunt males or females, participants indicated choice
of sex is driven by management practices protecting females and cubs, favouring large
males (Appendix 24). Many participants believed this practice sustains populations
and/or encourages population growth.
There’s a by-law for hunters and trappers so they have to go for the males. But if
there’s like no male they go out for the female…they’re [thinking] for the polar
bears…they don’t want the polar bears to [diminish]. (Interpreter for G5)
We [would] prefer more males ‘cause…there’s that law…you can’t take females so
much ‘cause they give birth and produce more polar bears…so that’s how it is.
(AB2)
When they’re hunting…they usually say don’t kill [females] with their cubs or only
when they’re male… ‘cause if they caught the female, there will ran out of bears.
(AR10)
Some participants preferred to hunt females and cubs before these practices were
implemented, while others would hunt any type of bear that they encountered.
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Before there was a by-law they could catch females—even [if] they got cubs, and
when after there was a by-law now they have to catch only males. The big ones.
(Interpreter translating for G3)
When they see a bear they don’t just shoot it…figuring that there’ll be a bigger one
coming up and there are other bears too that have cubs…They don’t go for bears
with cubs ‘cause it’s the law…or the policies—guidelines that they have—have to
follow. But back then when they were kids their parents used to go for any bear.
(Interpreter translating for K1)
Hunting preference also depended on whether bears were hunted for food, clothing,
and/or the sale of hides. Today, most participants prefer large, old males with thick, white
(clean) fur due to the high market value of their hides. Current 2:1 male-biased harvests
(following Memoranda of Understanding) have also reinforced these preferences.
When I used to go with my stepfather, he preferred the—for money-wise…the big
male…but for meat, for meat consumption…more fat, and softer meat, female…for
consumption, it’s important…and for money, they used to sell [hides] to the
Hudson Bay back then…the bigger the [male]…we used to get more money with
the bigger hide… nowadays money is more important, which seems than—the meat
is important too but we don’t starve like when we used to. Long time ago. (G8)
When they see a bear, knowing that there might be a bigger one around…they don’t
shoot the one right away and, plus the bigger the skins are they tend to cost
more…they don’t go for females since they have a cub…and their cubs are too
small so they don’t go for those…he tends to go for good fur…some bears have—
seems to have no fur on some areas—neck area…mainly male bears. Maybe from
fighting or something. (Interpreter translating for K2)
If by chance, if he had a choice, he’d go for the bigger one, because they’re more
expensive…and also how clean they are. Like if [the] bum part is really dirty then
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it’s harder to sell them because they—people want to buy clean, white [fur]…But
there’s also a [point] where if there’s not many choices in the bear, if there’s few
bears…they wouldn’t try to go for the skinniest one—the unhealthy one. And also
his third option would be is, if…they had to kill in defense. Then it wouldn’t matter
if it was female or not. (Interpreter translating for AR4)
In contrast, some participants still preferred small, young females for consumption.
I prefer younger…they’re a lot [more] tender…with female they tend to get tender
very faster…’cause I’m always cooking…[old] males, they’re a little harder ‘cause
probably they’re constantly walking and hunting…but females they’re mostly
feeding or just survive or something like that. (AB14)
Some participants preferred middle-sized bears.
He would try and get one that’s not too much of a cub…not too old—if he had a
choice, he wouldn’t go for the older bear ‘cause it’s leading the other bears…he
would try and get the one in the middle. (Interpreter translating for AR6)
Health was also important to participants who hunted polar bears for their hides and/or
consumption.
If it’s easy to clean that means it’s a healthy animal…whereas unhealthy one it’s
hard to scrape off the fat as much. (Interpreter translating for AR6)
Hunters across the north preferred different characteristics of polar bears that they
hunted, depending on their use. With the short time available for hunting due to tag
requirements and small harvest quotas, Gjoa Haven, Arctic Bay, and Arviat participants
were no longer selective for a broad range in bear characteristics. In contrast, Kimmirut
participants remained selective when hunting and some hunters were able to hunt more
than one bear per season. Unlike most communities, Kimmirut hunters rarely pursued
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bears and usually hunted them when they were encountered while harvesting other
animals; tags were distributed following each hunt and lottery distributions only occurred
when two to three tags remained to avoid overharvest.
4.4.2 Methods of identifying polar bear characteristics
Because of individual experience, preferences for bear characteristics, and harvest
regulations, it was important for Inuit hunters to identify and distinguish polar bear
characteristics when hunting. Participants identified bear sex, age, body size, and health
by observing the bear directly (e.g., body shape/size, fur, behavior) and/or its tracks (in
situ footprints). In Arviat, being able to identify polar bear characteristics was also
important to avoid potentially aggressive (dangerous) bears. Bears often frequented the
community in groups. Some community members compared individuals within groups to
distinguish characteristics.
[If] there were two bears, male and female, and you can tell the difference, like size
at the same time and you can look at the neck…longer necks and shorter necks.
(AR1)
4.4.2.1 Distinguishing males and females
Some participants indicated sex could be identified from tracks alone (Appendix 24).
Larger tracks were usually associated with males (versus females). Most participants
reported male footprints are generally angular and wide, whereas female footprints are
round and narrow.
The female footprints are mostly, almost round…females is shorter, male is longer
…when they’re males even they’re older or younger they’re long and big.
(Interpreter translating for G6)
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When you find the track, female…they’re more round…male tracks look [almost]
like triangle…more square, more triangle. (Interpreter translating for AB3)
An older male bear, their footprints are wider…whereas a female bear, the paw
print would be more roundish. (Interpreter translating for AR4)
Some participants used gait or footprint orientation to distinguish males from females.
Males tend to walk with a longer stride and their footprints turned inward. Some
participants also observed patterns along tracks for long fur of males.
If the snow is soft at the time the polar bear walked through there, [they] would
have fur drag marks, a big male…because the big males seem to have longer fur, on
the outside of the feet and the bottom of the feet…if there’s any nails broken that’s
a big male broken in fight...Or in [making a seal hole]. (G8)
Some participants indicated female movements are more direct than males.
When they see the prints, if they’re kind of straight footprints…they know it’s a
female…male, when you’re tracking their tracks, they don’t go straight they kinda
maneuver around. (Interpreter translating for K4)
Participants in other regions indicated the opposite.
Where he was taught, the mother bear usually is being followed by the cubs…so it
wanders back and forth, looking for seal…they know it’s a female leading, because
it’s, you know, turning. Whereas a male bear would walk straight, going by the
footprints. If the footprints are going straight…that means it’s like a male bear,
traveling by itself. (Interpreter translating for AR4)
Participants also mentioned sex was more difficult to determine in younger (smaller) bear
tracks than adults.
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The female bears’ prints are shorter than the male bears…he can tell that kind of
difference but if it’s a cub, not full-grown, he doesn’t quite know if it’s a male or
female too. (Interpreter translating for K2)
If it’s a smaller bear I can’t really tell [if] it’s a female or male…if they’re really
big, I know that that’s [a] footprint of a big male. (K9)
When observing bears directly, some participants indicated it is difficult to identify
sex from a far distance.
From a distance sometimes it’s hard when it’s not in the right angle…if it’s
completely sideways and you [can’t] see the neck. (AR1)
In the far distance when you see bears travelling they all look the same, but as they
get closer it’s easier to determine whether it’s female or not. By the fur, the back of
the neck…and the long neck. (AR4)
Participants also mentioned it is difficult to identify sex in older (larger) bears.
If it’s a male…same size as a female, if it’s fat you can’t really tell if it’s a male or
a female…but if it’s skinny, same size as female but you know it’s a male. (AB12)
If it’s an older bear, he wouldn’t know how to determine because the fur is
yellowing as it’s aging…so, the older the bear, then it would be more kind of hard
to determine whether it’s female or not. (Interpreter translating for AR4)
Participants across all communities associated larger body sizes with males. Participants
also used head and body shape to determine sex. Females tend to be more round, with
shorter “snouts”, and smaller heads compared to males.
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[Females] looks like they’re shorter and chubbier…and the males, they’re a bit
bigger and more slender kind of…the female, they might have what looks like two
forehead on top…and shorter face…and the male, they have the longer face...can
also observe the hind legs…[females] their tail looks like lower, and the males will
have a higher—their position—tail a bit higher. (AR5)
Arctic Bay participants generally indicated longer or narrower necks in females versus
males.
With the female, they’re more round…and they have a little longer neck…with the
males they got [a] thicker neck and they’re larger…they have a bigger head…with
the shape of their bum area. (AB14)
Arviat participants indicated the opposite.
You can tell by lookin’ at their ears…the distance. A females’ are gonna be more
closer…and shorter necks. And the male bears, their ears are gonna be more far
apart. And they got longer neck…you can tell by their legs, where they got all that
long hair. (AR1)
Seems like [females] got more short neck…from head to the body, seems like
they’re shorter. But a male, it seems like they’re always have their neck stretched
out. (Interpreter translating for AR14)
Participants described females as having whiter, “cleaner” fur, with dark coloration
around the crotch area, compared to males.
If it’s going—running away from him, and the bum area, if it’s not dirty, he knows
it’s a male…the female ones, when they’re heading away from him, the crotch area
is yellow. (Interpreter translating for K6)
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He can tell by the bum part whether it’s a female because they’re more—they tend
to be more yellowish. (Interpreter translating for AR4)
Participants also used behavior to determine sex.
By the movement you could tell they’re female…‘cause they’re like, cleaner. Very
gentler…whereas the male is [a] very aggressive kind and kind of walks
aggressively too. (AB15)
And a male…they never around with another polar bear…they don’t stick around
with a polar bear, and they got their movement—it’s more hyper…they always
aggressive like anxious and look around, look all over, but the female ones, they’re
a lot easier to tell. (AR14)
4.4.2.2 Identifying age and body size
Participants indicated that it was not important, historically, for Inuit to identify ages of
bears. Instead, body sizes were and continue to be of interest.
By Inuit knowledge they didn’t care about the age…when renewable resources
started asking for samples, then the government started finding out how old the
bear is. (Interpreter translating for AB4)
They know, yearly, like last year [cubling]…and estimating how height…what the
height is…they guess how old the bear might be…they don’t put actual age.
(Interpreter translating for K2)
Not by age but by size…only by size they look. (Interpreter translating for AR3)
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Participants from Gjoa Haven, Arctic Bay, and Kimmirut mentioned inferences on body
size can be made by placing their kamiks (traditional boots) together along tracks
(Appendix 25).
When they’re male, put your feet together and you could tell they’re big bears, [in]
the footprint. And when they’re female they’re small, smaller than [that].
(Interpreter translating for G7)
He wear caribou kamiks…just by the footprints, you put your feet near it…they’re
really fluffy, the kamiks…if it’s smaller than that they’re small. (Interpreter
translating for AB1)
By Inuit ways, they put their feet together to determine how big the bear might
have been…to his knowledge as he’s growing up that’s the only way the hunters
determined how big the bear might be…using their feet together. (Interpreter
translating for K1)
While few participants used tracks alone to determine age, participants associated larger
tracks with larger body sizes and older bears. Some participants mentioned bears reach
large body sizes quickly.
They grow really fast…they age really fast…like dogs have 7 years, for us, a year.
(Interpreter translating for AB4)
The height, if it’s last year’s [cubling] it’s that big …not many years, the bear cub
tends to grow as big as the mother…so, looking at the cub and the mother they
estimate the age of the bear. (Interpreter translating for K2)
Most participants used age categories versus chronological age (in years) to distinguish
bears.
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In Inuktitut there’s—we have names for yearling…second year, third year, and
those that are the same size as the mother…and then there’s a next to adult male,
young male, and big adult male…there’s names on every stage. (AB15)
The younger ones, you can[’t] really say exactly how old…you can see a
yearling…a cub that’s like full grown…you can guess like there’s like 2 or 3, 4
year old…a full year, like 2 years, 3 years, and when they reach their—where they
stop growing. And so I think they go from 3 to 4 when they [finally] stops growing.
(AR1)
Several participants mentioned that large, old bears—Tulajuittaq—that stay in open
water and never come inland.
There’s stories of polar bears that never go on land. There’s a term in Inuktitut,
they’re called Tulajuittuq, which means ‘they never go on land’…they always stay
in the moving ice...tula is to go, like a boat to go ashore…juit is never, and ‘doing
it’…so tula—land—not—do…they’re the biggest bear you’ll ever see.” (AB15)
There’s biggest and biggest bears and that doesn’t come to the town or, it doesn’t
go inland…he said that there are only few, few, less and less humongous
bears…[sport hunters] usually want to get the biggest bear that he was talking about
these bear that usually [not] hunting inland. (Interpreter translating for AR12)
Two participants indicated bears appear to be smaller, with less body fat, as they reach
older ages.
The big males…are older when they really can’t run anymore…they’re just
walking, even if their fur is nice…when they’re older, their feet…they’re bad…and
they’re a little skinnier than the younger ones. (Interpreter translating for AB10)
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When they get too old, I guess they’re not so good at hunting seals…so they get
really skinny. And they appear smaller…they have a better time hunting and are
successful hunting when they’re younger. And stronger I guess. (K9)
Arctic Bay and Arviat participants also used fur color to make inferences on ages of
bears; younger bears are associated with white (versus yellow) fur.
When they’re older, they’re more yellower…when they’re younger, their fur is
more beautiful and more white. (Interpreter translating for AB5)
He would use wolf for example. He knows with the wolf that the fur starts to get
more yellowish…so the same would probably go for bears, a healthy, younger bear
would have more white…the hide, would be more whiteish. Whereas an older
bear—older bear would start yellowing more. (Interpreter translating for AR4)
There’s an [Inuktitut word] meaning between a cub and a full-grown. There’s a
middle, category that we say…you can tell by the color of the fur whether they’re
reaching full adult or whether they’re still in their middle…stage. You can tell by
the color of the fur like how white it is, how, the fiber [of] the fur itself. (Interpreter
translating for AR6)
Participants in all communities also examined behavior; younger bears tend to run away
faster when being pursued.
The old one…they cannot run. They only walk…they’re very easy to catch…they
not gonna run from you, they’re just gonna walk very slow. (AB6)
Participants also indicated younger bears are more active and aggressive toward humans.
The big adult male, they’re kind of—they got confidence, when they’re
walking…slowly. They know that then they kind of just…move around. Slowly.
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Young one—young ones are very curious. They move around and…they look
around, they go into camps…they’re the one[s] that follow the people
more…‘cause they’re young, they don’t know, they don’t have experience.
Whereas the big males, they know not to bother the camps, so they don’t. They
kinda cool. (AB15)
Younger bears, you know, still might have a chance to breed or whatever [and] still
has to grow, and, kind of like adolescents, like they’re more mischievous or more
active. But older adults, they’re more relaxed, they don’t—they’re not as active.
(AR8)
Old polar bears, they’re not aggressive…‘cause they understand…they know when
we have weapon as they approach they can tell if we have a rifle or not…the
younger ones, they don’t seem, to have, knowledge if we have weapon or
not…they just approach…so we feel more comfortable with the older ones. (AR16)
At least one participant from each of Arctic Bay, Kimmirut, and Arviat communities
examined teeth from harvested bears to estimate age.
He thought that’s why the bear was old, some teeth were broken and chipped off.
(Interpreter translating for K6)
4.4.2.3 Identifying health of individual bears
When asked about health of individual bears, all participants indicated body fat and/or
size is a direct indicator of health.
If it’s skinny, it might not be getting enough to eat, or it—it might be sick…but I’ve
never really seen a sick bear. Like I just seen a skinny bear or, who’s had hard luck
of like, catching prey…all I know is like, they appear very unhealthy when they’re
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skinny…I guess when they’re not eating then—when they’re too hungry like they
appear, unhealthy. (K9)
When they’re unhealthy they’re skinny and tiny and when they’re healthy they’re
big…they’re chubby and big fat on their tummy…when they’re getting old, and
they’re—when they’re not eating enough—not enough they’re start to, skinnier.
Skinnier and skinnier. (Interpreter translating for AR13)
Three Arctic Bay participants inferred body fat by observing footprint shape (Appendix
26).
Polar bear, when they’re fat…their tracks are round…but the skinny ones’ just like
my foot. (AB6)
One participant observed gait from tracks.
When they’re skinny their tracks are closer to each other…and they tend to take
longer steps, like further steps…the nice and healthy ones, their—their tracks are
more apart…and their steps are closer. (Interpreter translating for K6)
Relevant to this, when observing bears directly, Arctic Bay, Kimmirut, and Arviat
participants indicated unhealthy bears move slower or in a more staggered and
unpredictable manner compared to healthy bears.
There was one time, he saw one bear that seemed sick so they didn’t go catch
it…the way, it was walking…hardly move, hardly walking…and when it stops it
stays there for a while…won’t move, he said. (Interpreter translating for AB3)
One time he saw a polar bear that seems like was drunk ‘cause it’s so hungry…it
was staggering…and he didn’t want to catch that one. (Interpreter translating for
K7)
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A healthy bear would walk in a more, straight fashion or, orderly fashion than an
unhealthy bear, kind of like a drunk person, not walking straight, walking around.
(AR8)
Some participants inferred health from fur color. White (versus yellow) fur was
associated with healthier bears.
You can tell by looking at it because with the healthy bear, the fur is shinier and
more, you know, clean looking…whereas unhealthy bear, it’s dirty…the fur’s not
shiny as much...[like humans] before we reach the adult we have good skin…so we
can tell by looking at our skin. (Interpreter translating for AR6)
Most participants indicated hunting ability or ability to acquire food affected health.
Well they’re just like humans…some of them are better…hunters than [the]
other[s]…some of them don’t know how to hunt…but they can kill somebody or,
kill each other…if they don’t know how to hunt seals. (AB6)
They’re like humans. Some humans tend to catch more animals and some hardly
catch anything and he believes bears are like that too. In order to be healthy some
bears who catch regularly, but some bears may not be catching regularly like the
healthy ones. (Interpreter translating for K2)
I saw one, big male, and you could just tell the ribs…the head’s even seems like it
was a huge head…the body was like—like just really skinny and you can see the
bones…I bet that bear didn’t even make it through the early fall. ‘Cause it wasn’t
even scared…I think he was not a very lucky bear to get a free meal from another
kill somewhere along the shore…sometime they’re just gonna get starve and, and
never regain their energy… they’re gonna miss, miss, miss, miss and—and they’re
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gonna be forced out from other bears and, so I think that’s they just start[ed] going
downhill. (AR1)
In the polar bear, like in a family…sometimes there is one bear…it’s always
hungry…they don’t share with it …they help each other, they feed each other, but
there’s always one bear that is always…thrown outside of the circle…so that one
ends up hungry all the time. He has to fend for himself, not with the group.
(Interpreter translating for AR3)
Some participants indicated health corresponds to changes in local prey populations.
When he was a teenager there were a lot of seals around. Young seals, the ones that
were born same year but they were together and there were lots of them...[then] the
bears started…being more populated around—around Kimmirut…nowadays
there’s hardly any seals…when he was a teenager he—they were catching
abundance of seal. So back then they were quite healthy. Seems like majority of the
bears that he saw were fat, and healthy…but nowadays there’s hardly any seals, he
knows too that they don’t only eat seals but like, vegetation around the land they
eat those but nowadays, with hardly any seals, some tend to be—look unhealthy.
(Interpreter translating for K2)
It’s hard for the bear to catch seals a lot, that’s when it starts losing it’s weight…it
helps them to get ready for the full winter…the seal meat helps them prepare, that
hey can help hibernate longer. So they try and eat as much seal…if there’s hardly
any seals around, like this [spring] time of the year, then the bear’s gonna be
hungry for longer [‘cause] they eat mainly off seal. (Interpreter translating for AR3)
Participants indicated bears that are more aggressive toward humans are less successful in
hunting, and are, thus, less healthy.
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When you will see a healthy bear, and when you see a track when you hunting
them, they go…scared away…they kind of run, right away…but a sick bear,
doesn’t care…you know, they lost that will…[to] get away…so they kind of just,
slowly, kind of walk away but not—not in a hurry…as if they’re trying to show us,
‘look I’m sick already…so don’t bother me’ ...kind of thing. But a healthy bear will
go, scattering away…very fast. Their fur is white too. The sick bear is yellow fur.
(AB15)
The less they eat, they’re gonna be more skinnier and more desperate…and not
afraid of humans when they’re hungry. (AR5)
Participants also described male-to-male and inter-sexual combat affecting body
condition.
Not really sickness that affects the polar bear from being skinny, it’s when they
fight males, they break muscles…or bones. That really stops them from hunting
‘cause they’re in pain…especially during mating season. (Interpreter translating for
AB4)
When they’re pretty old, you can tell, and by mating…season. They fight
sometimes to the death…or hurt themselves really bad…you can tell that it’s
hurting…their bones get broken. Their muscles are torn and all that…so it becomes
unhealthy…during that time. (Interpreter translating for AB12)
The female can fight the bigger ones…they’re really strong…those females they
really love their cubs…and when that big male started to get close to the cub. Then
that female start to—started to run after that big one, it’s trying to fight it—maybe
sometimes, they kill that female…I’ve seen that, couple of times...down at northern
Manitoba. (AR11)
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Participants provided insight into potential causes of recent changes and observations
related to polar bear (population) health. Many of these observations were made through
frequent opportunities to observe and interact with polar bears; these immediate
observations might not be made available through scientific methods alone.
4.5 Discussion
Participant methods and the ability to discern polar bear characteristics continue to play
an important role in hunting. Traditional skills in identifying characteristics associate
with personal preferences and experiences, which vary among communities and
community members. Hunters generally prefer larger males for trophy hunts and hides,
and females and cubs for food. Identifying sex is also important because of differences in
hunting challenges and hide preparation, as well as meat quality between males and
females. Although identifying age was not important to Inuit in the past, hunters today
associate fur quality and body size with age classes. Discussions over health always
involved implications for human use; many community members associate polar bear
health with food consumption, ease of skinning and hide preparation, and coloration and
quality of fur. Arviat participants—who experience frequent interactions with bears—
always identify polar bear characteristics that are associated with aggression, which have
direct implications for human safety. Personal experiences also shape the acquisition of
hunting skills, as is evident through participants frequently discussing hunting methods in
the context of their own concerns and priorities. This focuses on preference for personal
versus trophy hunting, or tendency to actively pursue versus avoid bears. These
observations have implications for the understanding and inclusion of IQ in polar bear
monitoring and management.
4.5.1 The role of Inuit methods of identifying polar bear
characteristics in monitoring programs
Community-based monitoring programs are attractive because they can supplement
scientific population data and, through participation, allow Inuit to inform management
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decisions that affect them. Inuit methods of distinguishing individual polar bears could be
particularly applicable in surveys for population abundance, sex and age structure, and
health condition, especially in years between comprehensive scientific surveys when
these data are not available. These methods could also complement scientific surveys
through Inuit participation, for example, in identifying individual bears to avoiding re-
sampling the same individuals. Inuit could also provide rapid preliminary sex, age, and
health information on individual bears without requiring physical capture, sampling or
untimely laboratory processing to collect these data. These data could be evaluated for
consistency for inferences on accuracy (Wong et al. 2011) prior to inclusion in
quantitative surveys.
While participants across communities generally agree in methods of identifying
sex, some inconsistencies exist, namely, whether males or females associate with longer
necks or snouts, or rounder footprints. These inconsistencies are also unique observations
that not all participants discussed. The lack of agreement could be due to new
observations that remain to be validated by other community members through extensive
practice (Alessa et al. 2015), or, similarly, inaccurate observations of inexperienced
individuals. It is also possible that differences in polar bear morphology and behaviour
occur across different regions (e.g., footprint shape) though this is more difficult to
confirm empirically. Such will require extensive scientific sampling and/or regional
comparisons of local reports of these unique observations. Inconsistencies or lack of
agreement among participant reports should be taken into consideration if these
observations are incorporated into any monitoring program. Group discussions where
participants and elders across communities are able to share their observations might
overcome or clarify any discrepancies.
The inclusion of Inuit hunters in any polar bear monitoring program should
consider the limitations of participant hunting experience and methods of identifying
characteristics. Some participants reported difficulty in identifying sex from far distances
and in some age classes of bears (old or young bears, depending on the hunter). Inuit
diagnoses of age categories (as a recently acquired technique) and body size might be
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more reliable or consistent than chronological estimates of age in polar bear surveys, as
participants indicated that historically chronological age was not important to them. For
Inuit, it may also be more meaningful to refer to categories of observations within their
traditional contexts rather than ecologically meaningful characteristics that scientists and
managers use, such as desirability of hide or tenderness and tastiness of meat versus sex
and/or age categories. The few instances where participants report examining teeth from
harvested bears also suggest community members may be learning from or are aware of
scientific methods (of aging polar bears using teeth; Christensen-Dalsgaard et al. 2010).
Hence, scientific methods may also shape IQ and TEK. Inuit participation in research
could provide unique opportunities for Inuit to become aware of—and perhaps build
on—what knowledge is relevant in scientific and decision-making. Research participation
could also allow both Inuit and scientists to see how observations that are important to
Inuit correspond to scientific and management relevant categories and vice versa. Clearly
defined terminology for categories according to the contexts of their application will be
necessary.
4.5.2 Comparisons between Inuit methods of identifying
characteristics and science
Identifying overlaps between TEK and science will not only facilitate dialogue between
Inuit and scientific researchers but also support the role played by Inuit in science-driven
research and management. Though Inuit focus on identifying characteristics that are most
relevant to them, community members from different communities and regions share
identification techniques that overlap with scientific methods. For example, participants
distinguish males from females by identifying larger head and body sizes, and presence
of foreleg guard hairs (Derocher et al. 2005). Hunters use age categories versus
chronological age to age bears just as used in mark-recapture surveys and population
viability analysis to estimate population structure (e.g., Taylor et al. 2006). Several
participants indicated younger males are more active, and activity is related to health
condition. Higher body condition associates with prime-aged (five to 20 year old) bears
due to their ability to survive nutritional stresses, such as their ability to hunt and take
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seals from subordinate bears (Regehr et al. 2007). Some participants reported higher
growth rates in younger bears, as empirical observations have reported (Derocher et al.
2005). Participants also indicated that, in their search for food, younger bears are more
likely than older bears to enter communities. This corresponds with the larger proportion
of young bears killed in defense of life and property across Nunavut (Dyck 2006). Bears
are also more likely to enter communities when food availability is low (Rogers 2011),
especially younger males due to naiveté or lack of risk-aversive behaviour. Participants
also linked health to fat and body size, and fatness indicates body condition in monitoring
programs (Stirling et al. 2010). Taken together, these observations suggest hunter-
knowledge can complement science in any polar bear monitoring and/or research
program.
Spending time with Inuit in search for polar bears (Wong et al. 2011) allows for
knowledge-gathering and ground-truthing, cultivating a deeper understanding of Inuit
interactions with polar bears, and experiencing how IQ is gathered and applied—
specifically, how IQ operates as a guiding principle for Inuit interactions with animals.
Unfortunately, most community members lack scientific experience and many
community members do not trust in science (Moller et al. 2004). Basic science is often
viewed as being inseparable from management because science largely informs
management decisions (Bocking 2007). Constraints on timing, funding, and logistics
limit most researchers from spending enough time in the north to interact closely with
what is being researched, on a level comparable to that of surrounding communities.
Such might explain the local criticisms against monitoring programs that are inadequate
in capturing local ecological phenomena (Moller et al. 2004). In areas where scientific
survey data are lacking and/or out-dated, there is also ongoing pressure for decision-
makers to adjust harvest quotas according to immediate (local) observations. Quotas
based on inaccurate scientific data can potentially lead to overharvesting, which can
result in detrimental and potentially irreversible population effects (e.g., Taylor et al.
2006). Instances where quotas are too small after incorporating defense-kills may also
lead to more frequent human-bear interactions (Stirling and Parkinson 2006, Peacock et
al. 2011, Vongraven and Peacock, 2011). Persistent long-term engagement of Inuit in
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scientific monitoring can facilitate a comprehensive understanding, at the community
level, of how science and IQ can synergistically inform management decisions; such
might assuage local misconceptions of both research practices (Pearce et al. 2009) and
IQ. Documenting IQ on population characteristics, beyond broad statements of “more” or
“less” bears, not only allows for a better understanding of the formation of IQ and polar
bear ecology but also provides Inuit with a chance to share their own ecological methods
and observations independently from science.
4.5.3 The role and persistence of Inuit knowledge in polar bear
management
Participant discussions indicate that harvest regulations continue to impact motivations
for gathering and transmitting knowledge of polar bear characteristics. The ability to
distinguish males from females is especially relevant to male-biased harvest regulations,
while body sizes remain important in protecting younger bears. Economic incentives and
demands for hides and sport hunts continue to drive the hunting of large males, which has
also been reported in other communities (Dowsley 2009b).
When he was young hunters were catching any bear they saw…back then when he
was growing up…he noticed the hunters were hunting any bear, even the cub, or
the mother…back then they used to not know whether if it’s a female or
male…they caught it whether it was female or male back then, but nowadays they
can tell the difference between the females and the males...nowadays they tend to
try and get the bigger bears. (K4)
Canada—home to two-thirds of the world’s bears (Peacock et al. 2011) and 70% of the
world’s legal harvest (Tyrrell and Clark 2014)—is the only country that allows
international trade of polar bears through aboriginal subsistence hunting. One might
expect the economic benefits of selling a tag to sport hunters outweighs the benefits from
personal hunting (Dowsley 2009b, Dowsley 2010). However, Arviat community
members indicate there is little incentive for sport hunting after expensive supplies (e.g.,
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oil and gas) and time-intensive labor (e.g., hide preparation and outfitting) are taken into
account. Arctic Bay community members also report frequent disputes during public
community meetings over the numbers of tags allocated to sport hunters. In Clyde River,
Nunavut, no more than 20% of hunting tags are devoted to sport hunts (Dowsley 2009b).
These reports together suggest a strong cultural value still persists in polar bear hunting
for personal (traditional) purposes.
With smaller quotas and hunting opportunities, younger hunters acquire less
experience and are unable to distinguish polar bear characteristics at the same level of
detail as elders and older hunters. Elders express concern about younger hunters’ lack of
in-depth knowledge of the ecological and ethical relevance of their hunting practices.
Elders and more experienced hunters frequently stress that IQ is experiential; knowledge
is gathered through active participation and engagement with animals on the land.
Hunting opportunities have been lost in some areas (e.g., communities overharvesting in
M’Clintock Channel which led to a moratorium [Taylor et al. 2006] and recent
reinstatement of a small quota), leading to abandonment of traditional practices. This
could result in overreliance on technology over IQ and youth with poor hunting practices
and ethics (e.g., Gomez-Baggethun and Reyes-Garcia 2013). Contemporary changes in
local wildlife authority and social structure of harvest management also affect the degree
IQ is integrated into increasingly Westernized and modernized northern communities
(Padilla and Kofinas 2014). Historically, IQ was used as an educational tool to promote
sustainable harvests, including ethics regarding relationships with animals and how
people should behave in society and their environmental surroundings (Natcher et al.
2005, Houde 2007, Berkes, 2012). This differs from following the prohibiting wildlife
management regulations today (Moller et al. 2004), such as harvesting only as much as
you need to avoid overharvest versus according to a quota. Community-based population
surveys and bear-safety programs hold promise to provide unique and frequent
opportunities for community members to interact with bears in non-harvest contexts. The
inclusion of youth as observers and/or assistants in research also encourages inter-
generational knowledge transfer while supporting researchers in outreach activities.
Because management decisions actively shape the formation of Inuit knowledge and
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persistence, policy-relevant projects that are guided by community interests and/or
concerns will enhance the preservation of knowledge.
4.5.4 Barriers to Inuit inclusion in polar bear research
Community members use the same observations and cues (e.g., fur coloration, body
shape, tracks) to make inferences on multiple characteristics of polar bears. The
integration of these data in a scientific framework through a systematic, objective manner
is challenging. Notably, IQ links intimately with the context through which it is formed
and, thus, is subject to misinterpretation when isolated (Houde 2007, Berkes 2012). As
opposed to conventional scientific practices where phenomena are treated as controlled,
isolated subjects of study, Inuit view animals as constantly interacting with humans and
their environmental surroundings and incorporate their observations as part of a holistic
experience (Huntington 2004, Berkes et al. 2007). This is evident through instances
where participants describe polar bear characteristics through comparisons with human
behavior. Community members –and scientific researchers alike—are also more likely to
note unusual patterns in local animal distributions, behaviour, disease or breeding failures
(Moller et al. 2004) based on their individually unique experiences (Huntington 2004).
Knowledge-holders are also selective in the type of information they share and interpret
as their own form of management (Parlee et al. 2014) according to their own political
interests, cultural values and status within their communities (Berkes et al. 2000, Padilla
and Kofinas 2014). When key knowledge-holders and/or local decision-makers (e.g.,
wildlife board representatives) do not view themselves as representing community voices
it is a challenge to establish representative community perspectives (Parlee et al. 2014).
These complexities make locally endorsed or cohesive policies that take into account the
broad range in community and participant views over large regions particularly difficult
to devise (Parlee et al. 2014).
Understanding how management goals affect Inuit and the animals that they
interact with will allow conservation decision-makers to consider the socio-ecological
impacts and receptivity of management decisions before implementing them. For local
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communities, understanding common conservation goals that underlie scientific research
and monitoring could perhaps reveal cultural incentives for hunters to apply existing
traditional skills in a contemporary conservation context. Inuit inclusion is critical for
conservation management across the north, as the fate of the polar bear will span social,
economic, and cultural aspects of Inuit communities.
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4.6 Appendix
4.6.1 Participant responses to interview questions
Appendix 24. Number of participant responses by community corresponding to
observations used to identify sex of polar bears. General comments indicate where
participants mentioned the observation but did discuss how that observation was used.
Observation
Community
Gjoa Haven* Arctic Bay Kimmirut Arviat
Footprint
General comments 1 2 3 3
Round in females, narrow in
males
4 1 0 3
Narrow in females, round in
males
0 0 2 1
Larger in males than females 7 7 6 7
Gait
General comments 1 0 1 1
Smaller stride in females
versus males
0 0 0 2
Male tracks more turned in
than females
0 2 1 3
Inferences made on behavior 0 1 1 0
Head
General comments 0 0 1 1
Shorter snout in females 0 1 1 1
Longer snout in females 0 0 1 1
Larger in males 0 2 1 2
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Body
Shorter in females 2 3 0 4
Longer in females 0 2 0 1
Longer in males 0 0 0 6
Larger in males 3 11 6 12
Comments on length 1 0 0 0
Comments on rump 0 2 3 2
Comments on back 0 1 0 0
Comments on legs 0 0 0 2
Comments on neck 0 0 0 3 * Includes the single Kugaaruk hunter that was interviewed outside of Gjoa Haven (KU).
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Appendix 25. Number of participant responses by community corresponding to
observations used to identify age and body size of polar bears; most participants
associated age with body size. General comments indicate where participants mentioned
the observation but did not discuss how that observation was used.
Observation
Community
Gjoa Haven* Arctic Bay Kimmirut Arviat
Footprint
General comments on shape 1 3 0 2
Longer in older bears 0 1 0 1
Rounder in older bears 1 0 0 0
General comments on size 5 4 3 2
Cannot determine from
shape alone
1 1 1 0
Cannot determine from size
alone
0 1 1 0
Comments on claws 0 2 0 1
Gait
General comments 0 2 0 2
Comments on activity and
behavior
0 8 4 6
Younger bears more active 0 2 3 3
Younger bears more
aggressive toward humans
0 0 0 4
Body
Size 0 2 10 8
Use of kamiks 4 2 2 0
Fur color 0 4 0 4
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Use of age classes 1 1 2 4
Comments on Tulajuittaq
(large bears that never come
inland)
0 4 1 3
* Includes the single Kugaaruk hunter that was interviewed outside of Gjoa Haven (KU).
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Appendix 26. Number of participant responses by community corresponding to
observations used to identify health in polar bears. General comments indicate where
participants mentioned the observation but did not discuss how that observation was
used.
Observation
Community
Gjoa Haven* Arctic Bay Kimmirut Arviat
Footprint shape
General comments 0 3 0 0
Behavior
General comments 0 6 2 0
Unhealthy bears more likely
to interact with humans
0 0 1 4
Unhealthy bears seem
“drunk”
0 0 1 0
General comments on
movement
0 7 4 3
Unhealthy bears move more
slowly
0 0 0 3
Body
Fatness 2 8 8 15
General comments on fur
color
0 3 2 4
Effects on health
Fighting with other bears 0 3 0 0
Hunting ability 0 4 7 7 * Includes the single Kugaaruk hunter that was interviewed outside of Gjoa Haven (KU).
Questions on health were generally not discussed during interviews with Gjoa Haven
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participants and were added to subsequent interviews with Arctic Bay, Kimmirut, and
Arviat participants.
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Chapter 5
Inuit perspectives of polar bear research: lessons 5
for community-based collaborations
5.1 Summary
Research partnerships with northern communities hold promise for capacity and
resilience against environmental changes. Given their historical relationship with and,
thus, ongoing concern for polar bears, Inuit communities are keen to participate in
monitoring programs. In spite of this, northern communities continue to show some
resistance to polar bear research and collaborations. Here, I summarize and report
interviews with four Nunavut communities on Inuit experiences with polar bears and
research perspectives. Research interactions reveal ongoing cultural, socio-ecological,
and ethical barriers to polar bear research projects. Research licenses and standardized
ethics procedures do not always guarantee collaborations. Adaptable research methods,
mutual understanding, and open dialogue are essential in forming strong research
partnerships with northern communities.
5.2 Background
Community-based collaborations between governmental or non-governmental
researchers, decision-makers and communities can build local community support for
adaptive policies (Berkes et al. 2007, Ford et al. 2010). In Canada, rapid environmental
changes are affecting arctic ecosystems and these compel northern communities to
participate in research (Gearhead and Shirley 2007, Pearce et al. 2009, Ford et al. 2010,
Armitage et al. 2011). Unfortunately, some research projects inadequately involve
community members and/or fail to address community interests and concerns
(Provencher et al. 2013). Ongoing barriers to establishing meaningful collaborations
include a historical lack of trust (Kendrick 2000), “fly in, fly out” research practices
(Gearhead and Shirley 2007) and colonial histories that have not served the interests of
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northern communities (Tester and Irniq 2008). Subjects that have high political interest
are especially challenging for forming and maintaining strong bonds between researchers
and northern communities. Disputes between Inuit and scientific communities over the
responses of polar bears to climatic change exemplify this concern (Dyck et al. 2007,
Dyck et al. 2008, Clark et al. 2008, Dowsley et al. 2008, Stirling et al. 2008, Vongraven
and Peacock 2011). A lack of data on population dynamics for some subpopulations
(Obbard et al. 2010, Peacock et al. 2011), varying degrees of local support for monitoring
methods (Dowsley 2009, Tyrell 2009), and harvest management decisions that seemingly
victimize northern communities (Clark et al. 2013) might further polarize views. It is
important to ameliorate the lack of local support for monitoring programs because
management decisions that incorporate the best available scientific and community-based
information continue to hold promise for the effective conservation of polar bears
(Peacock et al. 2011, Dowsley et al. 2013, Tyrell and Clark 2014). It is critical that all
researchers form strong relationships with Inuit communities to ensure support for
management decisions founded on scientific- and community-based information.
It is necessary to engage communities throughout all levels of research—from
research proposals to disseminating results—to support community ownership of
research outputs (Buytaert et al. 2014), integrate local priorities in decision-making, and
sustain long-term collaborations (Pearce et al. 2009, Grimwood et al. 2012, Brunet et al.
2014a). Accordingly, researchers have encouraged a shift from “participatory” to more
active, “partnership” roles played by northern communities in collaborative research
(Gearhead and Shirley 2007, Brunet et al. 2014a, Tondu et al. 2014). Community
members consult as well as actively shape research throughout all stages of the process.
In Nunavut, community consultations and participation are mandatory (e.g., through
permits; Indian and Northern Affairs Canada [INAC] 1993). For research involving
traditional ecological knowledge (TEK) and Inuit qaujimajatuqangit (IQ)—historical
observations, experiences, and values in relation to environmental processes that are
passed on from one generation to the next (Berkes 2000, Wenzel 2004)—territorial,
institutional, and local levels usually require approved ethics protocols. Northern
community members usually review ethical procedures and require evidence of local
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consultations a priori (INAC 1993, Inuit Tapiriit Kanatami [ITK] and Nunavut Research
Institute [NRI] 2007, CIHR et al. 2010). From a practical standpoint, local experience
and knowledge benefits fieldwork safety and travel in remote and unpredictable
environmental conditions. But, to encourage support for research outcomes, it is essential
to go beyond the minimum institutional (both government and academic) requirements
for community participation in any research program.
Efforts to develop strong partnerships with Inuit communities are underway in
ecotourism development (e.g., Dowsley 2009), climate change mitigation and adaptation
(e.g., Ford et al. 2010, Pearce et al. 2010), and the management of natural resources (e.g.,
Grimwood and Doubleday 2013) including wildlife (e.g., Freeman and Wenzel 2006,
Kowalchuk and Kuhn 2012). The inclusion of Inuit collaborators in scientific monitoring
programs can gain support for wide-ranging management applications, going far beyond
those offered by scientific methods alone (e.g., Garnett et al. 2009, Buytaert et al. 2014,
Huntington et al. 2014, Moller et al. 2004, Phillipson et al. 2014). This can involve the
encouragement of public understanding (Reed and McIlveen 2006), inter-generational
transfer of knowledge (Garnett et al. 2009), and innovative ways to gather new
information (Phillipson et al. 2012). However, how to integrate IQ and science in a
complementary manner that does not compromise the integrity of either source of
knowledge remains an ongoing challenge to resolve. Though IQ includes traditional
TEK—a component of IQ that comprises measurable knowledge of ecological
phenomena (Berkes et al. 2000, Berkes et al. 2007) that is relatively easy to incorporate
into research and co-management systems (Wenzel 2000)—IQ includes guiding
principles for Inuit actions (including thoughts) and how these processes can affect
biophysical phenomena (Wenzel 2004, Dowsley and Wenzel 2008). Documenting IQ is,
thus, more challenging than documenting TEK because it is an experiential system based
on internalized norms, which are not amenable to observation (Wenzel 2004). IQ holders
see themselves as part of the inter-related phenomena under study (Berkes et al. 2007,
Houde 2007). In contrast, scientific methods emphasize cause-and-effect relationships
and objective, quantitative procedures (Moller et al. 2004) that separate researcher and/or
observer perspectives from their conclusions (Huntington et al. 2004). TEK literature
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also continues to separate indigenous and scientific knowledge in a paradoxical way;
scientific and indigenous knowledge have been used to validate one another (Agrawal
1995). Still, separating these lenses of viewing reality may undermine overlaps between
both types of knowledge and this should be recognized (Agrawal 1995). Both science and
IQ emphasize repeatability, analyses, and prediction gleaned through empirical
observations, albeit in differing ways (Huntington 2000).
The inclusion of IQ in monitoring programs allows knowledge-holders to
continue to use their skills and benefit from employment (Pearce et al. 2009) while
documenting and safeguarding knowledge for future generations. Few studies highlight
the key elements and procedures necessary to establish research relationships with
northern communities within specific and political research contexts (but see Pearce et al.
2009, Huntington et al. 2011, Grimwood et al. 2012, and Tondu et al. 2014). It is
possible to cultivate collaborative support for northern research by drawing from
examples on how to develop meaningful relationships with non-academic (e.g.,
indigenous and public) communities and stakeholders (e.g., Rowe and Frewer 2000,
Mercer et al. 2008, Phillipson et al. 2012) in non-Arctic contexts. Documenting IQ can
also engage and build relationships with northern local communities while allowing
researchers to identify unanticipated community perspectives, contexts, and other types
of knowledge that communities can share, including unique ways of community
participation.
For polar bear researchers, building relationships with Inuit can promote an
understanding and appreciation of nonconventional methods of knowledge formation. It
can also reveal persisting political and cultural barriers that may stagnate collaborative
efforts on the part of communities and researchers alike. Driven by the common goal of
better understanding polar bear ecology and the desire for community members to voice
their concerns, I report and summarize Inuit experiences with research. While quotations
include IQ and TEK of polar bears, I focus on Inuit views of polar bear research and
management in scientific contexts. I report on interviews with 23 hunters and 33 elders
(48 men and 8 women) in four Nunavut communities that range in their experience with
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polar bear research. I highlight ongoing challenges with polar bear research and
emphasize research practices that can improve support for research and monitoring
efforts, ensure better collaborations with Inuit communities and, ultimately, garner more
complementary biological and environmental data.
5.3 Methods
Over eight years of northern polar bear research in Nunavut provided me with the context
and experience to conduct this research. Collaborations with the Gjoa Haven Hunters and
Trappers Organization (HTO) began in 2008 during an independent project integrating
Inuit traditional ecological knowledge TEK of polar bears in a noninvasive survey (Wong
et al. 2011, Van Coeverden de Groot et al. 2013). This fieldwork allowed me to witness
firsthand the different relationships, experiences, and levels of enthusiasm and
engagement that Inuit hunters and elders have with polar bears and polar bear field work.
Camping on the land was often associated with unpredictable, physically and mentally
challenging situations. This provided unique opportunities to develop interpersonal and
adaptable research skills. It also provided context for subsequent interviews.
Interviews followed methods detailed in Chapter 4, but expanded on Inuit
relationships with polar bears and recommendations for polar bear research and
monitoring, which became the focus of this chapter. Briefly, HTOs prescribed and led all
recruitment procedures (radio announcements, flyers, and/or recommendations by other
community members), which varied in effectiveness among communities. HTOs also
recruited interpreters except in Arviat, where the Hamlet recommended an interpreter. I
recruited interview participants through a combination of key informant and snowball
sampling methods (Marshall 1996). In Arviat, most community members were familiar
with polar bear management regulations and research methods, and interview data
became saturated; no new themes emerged with additional interviews (Hsieh and
Shannon 2005). As in Chapter 4, participants were identified as “hunters” and “elders”
according to experience (active hunters, non-active hunters, and less-experienced
hunters) and names were coded to protect confidentiality.
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Semi-structured interviews included discussions on polar bear hunting, population
dynamics, monitoring, and management. As most initial participants steered interviews
toward their own views of polar bear population ecology research, subsequent interviews
included an opportunity for participants to describe what they felt was the “best way to
research and survey polar bears”. Generalized questions ensured conversations were not
encouraged in a leading way and follow-up questions that were posed as a response
encouraged participants to produce their own understanding and thoughts and clarify
information that was being discussed (Huntington 1998).
Interviews were analyzed as in chapter 4. I identified unique perspectives and
reported the quotations and participant information that I felt best described common
themes and categories. In 2015, I made a second trip to Arctic Bay, Arviat, and Kimmirut
communities to discuss initial results, perspectives at a broader community level, and
desirable research applications.
Outside of interviews, I spent time exchanging cultural views and stories,
familiarizing myself around town, and participating in community activities (when
invited) with community members and students. These interactions were exceptionally
important in cultivating trust, transparency, and comfort in sharing research perspectives
and understanding community priorities. Spending more personal time prior to data
collection through multiple visitations might have further strengthened participant
understanding and engagement (Pearce et al. 2009, Huntington et al. 2011, Grimwood et
al. 2012, Tondu et al. 2014).
5.4 Results
From May 2011 to April 2014 over four visits and one visit in February 2015, I
conducted individual interviews with 23 hunters and 33 elders (48 men and 8 women)
comprising 33 active, 14 non-active, and 9 less-experienced hunters. In February 2015, I
interviewed one additional active hunter. Interviews ranged from six to 63 minutes in
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duration on the land (for Gjoa Haven hunters and KU1) and at participant homes, hotels,
and HTO offices. Appointed interpreters translated 27 interviews. One Arctic Bay hunter
translated another participant’s interview prior to being interviewed. One Arviat hunter
translated six interviews following her interview, as the local interpreter was unavailable
due to illness. While questions initially focused on experiences with and perspectives on
polar bear population dynamics, monitoring and research practices, participants raised
concerns that pointed to cultural, ecological, and ethical considerations in research that
they felt needed to be shared with researchers.
5.4.1 Cultural factors affecting participant responses to research
questions
Several cultural considerations could have influenced participant responses and
involvement in TEK research, which extend beyond polar bear knowledge. The
interpreter in Arviat cautioned that modest participants responded with short answers and
it was frowned upon to “boast” about experience and/or knowledge. This ethic might be
so respected that participants provided vague responses or did not answer questions
directly. Arctic Bay and Kimmirut participants also touched upon some of these themes:
…[Polar bears] should not be bothered...don’t make fun of them or you know,
traditionally we were told ‘no don’t talk about animals in a negative way’…and
never say that you’re a great hunter too. Because if you say ‘oh I can get a bear’
the bear will teach you a lesson…so they told us ‘no don’t brag about polar bears,
that you’re able to hunt them’…even questions about hunting bears is kind of
very touchy too, for elders especially. I could tell that they don’t want to
answer…because they’re afraid…because it’s not something that Inuit talk about,
just bragging about it, [you know] it’s…vital…important subject, animals. Any
animal. Not to talk about them, not to bother them…leave them be, you know.
(AB15)
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The interpreter in Arviat also advised that Inuit were taught to “do as elders say”. Thus,
some interview topics were never questioned or doubted among community members.
Some knowledge and experience was deemed a “matter of fact”. Participants also
emphasized the importance of oral tradition.
…Those elders here…in Nunavut there’re [a] lot of uh, they know everything like
they have a lot of knowledge about life, or look after their family and so, they
know everything…the elders…like from young to…middle age. Taught them
how to be alive…but they don’t write it down because they have their knowledge
in their head…rules…in their head because we didn’t have any—or Inuit didn’t
have any paper or pencil so [they] have [it] in their head…so that’s…the Inuit
culture…we carry on…I carry, and now I told to my young family, my family, so
they started to know…so they’ll be know Inuit knowledge…like we don’t educate
by writing down...by looking at [it], by listening, and by doing it, we learn. (AR9)
The interpreter in Arviat indicated chores at camp were often distributed among family
members. Thus, while some individuals did not have practical experience, they were
familiar with technical skills through observation. Relevant to this, all participants
indicated they learned how to hunt by observing and/or camping with other (older) family
members.
By the age of 10 he started going with his dad to go hunting…he wasn’t really
taught how to hunt…he was watching his dad…but now he realized that he was
being taught how to hunt…but he didn’t know that he was being taught…just by
watching his father hunting…just looking at him, seeing him and he learned how
to hunt. (Interpreter translating for AB1)
Thus, Inuit share knowledge through experience as a “way of life”. Researchers should
become aware of and open to unanticipated responses and potentially sensitive topics.
Communities also stressed the importance of gathering knowledge through experience.
Spending time outside of communities (on the land) with community members can
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expand dialogue and encourage accurate interpretations of interview discussions while
establishing inter-personal relationships.
5.4.2 Inuit observations of polar bear ecology
All participants reported having more bear encounters in recent years than in the past.
Some participants indicated that the bears they have encountered were healthy.
…Last year he said that there’s more bears that are more fat…they rarely see
unhealthy bears…the only time they would see one is when it’s pretty old…it
won’t hunt—hunt as much…and it’s skinny. (Interpreter translating for AB9)
Others indicated the opposite.
Since they’re getting hungry, the polar bears…they seems to be declining in
fatness. So they’re skinnier one…lack of uh, food… the year before one that he
caught seems skinnier than the one that he caught last year…due to lack of food.
(K7)
Some participants attributed interactions with bears to cyclical changes in polar bear
distribution.
Back then there used to hardly be any bears…1920s, the father-in-law said they
used to go miles and miles by dog team, or by walking to go hunt polar
bears…but after 1980s, to now there’s a lot of bears…1920s, his father-in-law
was saying that there were a lot of bears back then…few years later they were all
gone…and now they’re all back…I think it goes like that, back and forth. (AB12)
Our elders, they say, they migrate, into other area…for years, and then they come
back…that’s what we’re experiencing now…back in early 80s, and mid 90s, there
were hardly any bears…there’s too many polar bears now. (AR16)
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Some participants linked these changes to food availability.
They go where there’s more food, you know…they always look around, they
can—they walk around everywhere for—look for food…so, if there’s more seals
down there they’ll be right there. (AB6)
And nowadays we tend to see bears close by Kimmirut…he doesn’t really know
why but he thinks it’s uh because they go—they follow their food…the more
hunters catch around the community…or just outside the community, the more
[bears tend to come] where the hunters hunt. (Interpreter translating for K1)
Despite climate change effects, many participants indicated bears were able to learn from
and/or adapt to changing environments.
He said he don’t really know about if [melting ice] affect the polar bears but he
said the um polar bears could stay in the water…they could go on the land. And
like, before they go on the ice they eat um, grass or from the land and they stay on
the ice…before they go on the ice and lay—laid down or rest or something they
eat grass so they don’t have to get hungry right away. (Interpreter translating for
GH3)
…Bears can catch seals even—even if the—if the ice is really thin…they’re great
hunters those bears…they’re really smart…they know how to survive…even if it
was just in the water floating, seal go by him and just grab it and eat it. (KU1)
All participants felt bears were more aggressive toward humans now than in the past.
Bears are really knowledgeable…they know now they won’t be caught…they’re
like humans…way of thinking that nobody’s gonna take them [to eat]…and that’s
why they’re smart as—they’re more aggressive and there’s [potentially] more of
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them now…the polar bears know that they won’t be shot at…now, but back then
they used to be afraid…knowing that they’ll be shot. (Interpreter translating for
AB5)
Arviat participants were particularly concerned with declining health in bears attracted to
and feeding at local dumps.
In the early 70s, ’65 to 70s, there has been increased in seeing bears around. And
yes we see more if it, they’re not healthy…because they eat a lot at the
dumps…before the 70s, it was much cleaner, you know, the tundra was much
cleaner, the town was cleaner but these days we have dumps…in most
communities. And that’s what they go for, so most—most bears, when they’re
hun-hungry enough they’ll go looking for food at the dump…and it’s getting
more and more frequent because of the dumps that they go looking for food.
(AR4)
Arviat residents have faced heightened safety concerns (Stirling and Parkinson 2006,
Kotierk 2010, Peacock et al. 2011) and being able to identify and respond to aggressive
bears has been and remains an ongoing priority. This was evidenced through participants
sharing knowledge of aggressive bears even when the topic was not addressed directly.
…A group of three or more? The lead bear, if he doesn’t attack right away, the
rest won’t…and if you’re approached that close? You don’t move…you don’t
make quick movement[s], you don’t move, you just sit still, because you’re
watching the lead bear…you don’t provoke it…you don’t even make any noise.
Like even coughing. (Interpreter translating for AR6)
…An elder always go through the radio… worried about young people, ‘Don’t
walk away so far’ or something like that. There’s always somebody encourage or
like, announce it on the radio… ‘Keep an eye, keep—keep look[ing] around,
when—when it’s dark’…there’s always somebody saying something about the
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polar bears, what to do and what not to do. (AR14)
Interestingly, participants across all communities indicated females and younger bears
were more likely to enter communities versus males and adults, respectively.
…The big adult male, they’re kind of—they got confidence, when they’re
walking…they kind of just kind of move around. Slowly. Young one—young
ones are very curious. They move around and [you know], they look around, they
go into c-camps, and you know, they’re the one[s] that follow the people
more…‘cause they’re young, they don’t know, they don’t have experience.
Whereas the big males, they know not to bother the camps, so they don’t. They
kinda cool. (AB15)
...They’re gonna bring their cubs right to the dump… they’re gonna show their
cubs where they can find their—their free meal? And the cubs grew, and, even
though they’re not with their moms anymore they—they’re gonna remember and
they’re gonna come back to the site, or to different places and they’re gonna find
whatever scent they…smell? (AR1)
Documenting observations of polar bear ecology offered elders and hunters a chance to
voice their personal observations and perspectives, regardless of agreement with
scientific views. Community members can offer a more nuanced understanding of
population dynamics than science alone. Polar bears are not isolated objects of study;
they also react to human interventions.
5.4.3 Management perspectives and recommendations for polar
bear research
Even though hunting regulations were implemented recently, participants stressed that,
historically, polar bears were harvested responsibly, sustainably and respectfully. When
learning how to hunt, young hunters are taught ethical responsibilities in addition to basic
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hunting techniques.
We always get enough food for the year we don’t try to finish all the bears we just
get enough. [When we get] what we need…we say stop or [even] any
animal…when we go out we check the tracks for fresh tracks, if we see them
sometimes when there’s bears with cub—young cubs we just don’t bother them
we just go after one single bear…when we have enough food for the family we’ll
always stop…we been controlling our animals…ever since long time ago…so we
could control it for our—the bears… ‘cause we don’t grow food…up here, that’s
one of our main diet…even without tags. (KU1)
…Bears are not just a game…and they’re not for pets. (K5)
…The older people, they know…how to handle them and [because] our parents
used to tell us not, to kill too many animal because what you need, just kill what
you need. No more than [that]. So that’s what’s, our rule is…Inuit. (AR9)
Some participants felt scientific and management practices (e.g., quotas and male-biased
harvests) have increased bear abundance.
But ever since I started growing up in Kugaaruk there’s way more bears than
when I used to be a small or young…today there’s a lot more bears now ‘cause
the hunters don’t kill the mom with uh females with little cubs anymore. (KU1)
The government specifically tells each community [how] many bears to
hunt…and not enough tags are coming into the community and that’s why the
population is growing. (AB9)
Some participants expressed concern over male-biased harvests and felt males were
important in maintaining populations.
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…There’s a by-law now and like they have to go for only males and he asked that
person how come like if you catch all the males and there’s no more males…how
they gonna make cubs…he said he don’t believe that there’s only one male and
there’s lots of females they gonna make lots of cubs ‘cause they always make
cubs only once a year…same time. (Interpreter translating for GH3)
Participants were aware of mark-recapture methods (ear tags, tattoos, collars, and
tranquilization) used to monitor polar bears. Most participants have collected scientific
samples or were aware of harvest-based sampling.
…They gave us an example of how they counted polar bears and they used uh,
beans. They had a whole bunch of beans and then white beans of some sort and
then they—they opened that and then they colored…so many beans and then they
thrown them back in there, they shook it and then they grabbed a handful…and
then there’s a couple of beans, that they grabbed and then—and then the rest are
not colored so they determine the population in each area that way sort of…so,
yeah that’s exactly how they do it. With the tattoo…so instead of just coloring the
bean, they tattoo the bears. (GH2)
Participants were also concerned with loud aerial surveys that negatively affect bears,
which are sensitive to noise and depend on sound to hunt.
…Polar bears are hunters. They need their ears to hunt seals. ‘Cause they’re under
the sea…I mean the ice. They need the ears for sure and they are ask when they’re
working, in an environment that’s really loud, they’re asked to use ear
protections…so they won’t damage their ears. Helicopters tend to damage
ears…and the polar bears are more skinny ‘cause they’re not successful in their
hunt…skidoos more safer than the helicopter. (AB12)
Participants also felt tranquilization continues to affect polar bear meat for consumption.
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You can tell, if the bear is healthy, or not…if you catch a—one with the
tattoo…on the lip…even cooking it you can tell that it’s unhealthy
sometimes…the water—they’re boiling in…it’s a little whiteish. (AB11)
Due to ongoing concerns, participants provided broad and specific
recommendations for monitoring and research methods. Some participants preferred
noninvasive versus invasive studies, reminding researchers to treat bears with respect.
He said it’s better if you don’t put them to sleep and looking at the footprints
instead to study. (Interpreter translating for GH7)
I think the way we’re doing now it’s—I think it’s better to count bears and…
‘cause we’re on the ground…we don’t put them to sleep or anything we just see
them and let them leave…we can always tell whether there’s more bears or less
bears as—as a—‘cause we keep going out rather than hunting bear only we—we
go out on the sea ice all the time. (KU1)
Participants recommended all surveys take into account bear movements, seasons, and
ice conditions, as surveys using transects and random sampling regimes (Buckland et al.
2001) incur a sampling bias (e.g., individuals in difficult-to-access areas).
Sometimes there are surveys being done on polar bears but they don’t catch all of
them, or they don’t see all of them…it’s kind of impossible. He has been on the
helicopter too when they’re surveying…it’s—you can’t [nitpick] any bear,
like…sometimes they’ll miss…when they’re following the tracks by helicopter, if
they’re zigzagging or going everywhere, uh, they tend to get air sick…following
the tracks. (Interpreter translating for K6)
Community members also emphasized the importance of spending time making
observations in the field and including local knowledge could help interpret scientific
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findings. Participants continued to support and in some cases prefer harvest-based sample
collection.
For his opinion, he’d rather have a polar bear killed…get the meat sample and the
fat sample and send that down…to be analyzed, why the polar bears are getting
sick…[he] doesn’t want anyone coming up here, so they won’t be scared off…so
they can be healthy. (Interpreter translating for AB1)
He prefer not to have them surveyed…he prefer uh when the hunter catches
on…uh the fat, the meat, the penis, the heart and all that be sent down instead of
them coming up here…and survey and research them…they use helicopters to
tranquilize the bears …and the tranquilizer, medication I think, is still in the body
and he doesn’t want that. (Interpreter translating for AB12)
Unfortunately, many community members were not aware of why researchers are
interested in polar bear samples or how samples could be used to monitor polar bears.
Few times we did on our sporting hunting uh with the polar bear and there was a
scientist came along to, to survey and…test out the polar bears and stuff like
that…I didn’t really learn it…they were on their own doing stuff. (AB2)
They don’t report back…if they’re given samples…and they don’t tell them why
they’re collecting, [what] they want those samples for…the only way that you can
get those is ‘cause the hunters are giving those to the GN (Government of
Nunavut)… he feels it would be nice if the GN or whoever they sent the samples
to are—if they can get feedback on those…they must know as to—if you receive
the samples, where it might have come in from…and they would know accurately
a—if they’re given feedback of how old, and…was that bear healthy or unhealthy.
(Interpreter translating for K1)
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Interestingly, the differentiation between academic versus government researchers was
not clear in these discussions, and several participants discussed research in the context of
academic and government research interchangeably. Management and research practices
should consider long-term ethical and ecological impacts on local communities and polar
bear populations, which will differ across the north. Explaining how scientific polar bear
surveys (biological sampling, fieldwork, and data collection) are designed, their
limitations, and the inferences that are made from sampling data to community members
could resolve some criticisms against these surveys. Some academic and government
researchers already make these efforts, suggesting other factors that limit access to or
understanding of scientific information and materials might be at play. These
implications are not always immediately evident through initial community consultations
or scientific literature. For example, communities across the north differ in levels of
experience and engagement with research that might only be revealed through
establishing relationships with community members to identify levels of communication
and reporting back that are required.
All participants felt including Inuit hunters and TEK can enrich polar bear
research with historic, holistic and contextual insight to improve projects and achieve
common research goals. Participants were especially supportive of efforts that allow
elders to share their stories, experiences, and perspectives.
…All the hunters are usually out, along these leads…they always have a story to
tell, if they see a bear…how many bears they saw, they’re reliable
information…so that information were used to determine—let’s [say] caribous
were caught in this area, how many. Like the same with the polar bear, ask the
hunters if they saw anything, if they found a bear here…other hunter does found a
polar bear here, we can determine if it’s the same bear if they’re close
together…so we could tell by what day the hunter saw that, what day the other
hunter saw that…they could tell ‘yeah that’s a different bear’…so that way we
could tell, and the seasons too, are different. Like right now, they’re in the
den…summertime we know most of them are around the coast. (AB15)
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Community members were able to provide specific recommendations in research design
and encouraged the inclusion of hunters and elders, suggesting communities could
inform—and recognize value in—collaborative research.
5.5 Discussion
5.5.1 Lessons learned from community-based interactions
In this study, few community research priorities were discussed during initial HTO
meetings. Community-wide concerns only became evident after subsequent interactions
with community members and multiple visitations, where time was spent to allow
community members to understand research objectives and resulting outputs. Participant
recruitment was especially challenging in Arctic Bay due to previous misrepresentation
by (and, thus, lack of trust in) non-local visitors and was only successful after
broadcasting a live radio show, where respected community members were able to phone
in and ask questions about research objectives and also show support for this work.
Similarly, local support and encouragement by other community members facilitated
participant recruitment in all communities.
Through their own enthusiasm in and understanding of research objectives,
interpreters were especially important in affecting the willingness of community
members to participate in this work when approached. Interpreters also provided a
contextual background for interviews through their own participant observations and
experiences, such as identifying reputable community members and instances where
participants might have held back responses. While research experience varied among the
interpreters, each interpreter influenced the research process in some way. The Arctic
Bay interpreter had no previous experience with research participation, yet introduced
this research to participants without the researcher’s intervention and also shared her
support for TEK work outside of interviews. Interpreters in Gjoa Haven and Kimmirut
were more reserved—displaying little evidence of their own research perspectives—and
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interactions were largely research-oriented, creating a more “formal” atmosphere for
interviews. The Arviat interpreter was a recognized translator and asked to review the
interview guideline prior to interviews so that she could anticipate how participants
would respond to some questions and guide participants toward research themes of
interest. AR10, who translated six interviews in Arviat, had no previous experience with
translations and in some cases responded to interview questions directly without the
participant’s response (as her own responses), suggesting her focus was on the “true”
answer to particular questions versus unique participant perspectives. In this manner,
research participants not only shape the research and knowledge-gathering process but
also influence how community-based research is perceived and received by the
community. Research practices that are culturally acceptable and effectively meet
community priorities differ from community to community and following ethical
guidelines and permitting processes does not necessarily guarantee local support (INAC
1993, ITK and NRI 2007, CIHR et al. 2010). These standardized and institutionalized
processes do not account for community-specific preferences, past experiences with
research, and capacity for research engagement. Spending as much time with community
members as early as is feasible in the research process can allow researchers and
communities to overcome any cultural barriers and establish the capacity to mutually
understand and appreciate scientific- and community-based applications. Unfortunately,
funding agencies do not always provide room in budgets for initial community
interactions, relationship-building opportunities and meetings for research validation and
completion. Training for researchers to establish these capacities is also lacking. Despite
these limitations, efforts made by researchers to understand and engage with communities
are critical and morally necessary because researchers and Inuit are impacted by research
in different ways. Research directly impacts Inuit livelihoods and their relationships with
their surroundings.
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5.5.2 Overlaps between polar bear TEK with science and other
TEK studies
Though polar bear TEK has been documented in Arviat (Arviat Hunters and Trappers
2011, Kotierk 2012), Gjoa Haven (Keith 2005), and Kimmirut (Kotierk 2010), no studies
of TEK in Arctic Bay have been published and individual views and perspectives are not
necessarily generalizable across communities and Inuit as a whole. Building on polar
bear TEK literature, this study serves to voice detailed Inuit perspectives from different
Nunavut communities and regions. Participants were able to share—and in some cases
reiterate—their own views within a research (versus management) context, make specific
recommendations on monitoring practices, and highlight themes that they felt were
important. This work also allowed community participants to ask questions about current
polar bear research and scientific methods and how data could be used to inform
management, from a research perspective.
Several ecological and scientific views expressed by community members align
with previous TEK studies. Participants in this work shared views that are consistent with
reports from Pond Inlet, Qikiqtarjuaq, and Clyde River (Dowsley 2007, Dowsley and
Wenzel 2008) and Pangnirtung and Iqaluit (Kotierk 2010). Across the north, Inuit still
report recent increases in polar bear abundance and the ability of polar bears to adapt to
rapidly changing environments (Keith 2005, Tyrell 2006, Dowsley 2007, Arviat Hunters
and Trappers 2011, Kotierk 2012, Kotierk 2010). Consistent with previous TEK,
community members warn polar bears are dangerous animals (Keith 2005, Kotierk 2010,
Kotierk 2012) and some Inuit are weary of consuming polar bears that have been eating
garbage (Arviat Hunters and Trappers 2011). In the past, community members have also
reported dissatisfaction with scientific methods (Tyrell 2006) and the level of influence
that Inuit have in management (Kotierk 2010). Together these reports suggest Inuit share
concerns that are ongoing and wide-ranging across the north, and persist despite efforts to
integrate them through research collaborations and co-management (Peacock et al. 2011).
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Across communities in this study, participants reported increasing bear encounters
are an adaptive response to dietary changes, which has been scientifically reported in
Western Hudson Bay, where bears are seeking alternative food sources around
settlements (Stirling and Parkinson 2006, Government of Nunavut 2012, Gormezano and
Rockwell 2013b). Though dietary changes have been attributed to sea ice changes
limiting access to primary prey (ringed and harp seal; Thiemann et al. 2008b), evidence
for bears foraging on land-based foods (Dyck and Romberg 2007, Gormezano and
Rockwell 2013a, Rockwell and Gormezano 2009)—reported as typical behaviour by
most participants here—might also suggest an opportunistic feeding strategy (Thiemann
et al. 2008b), where bears pursue readily available food sources even in the presence of
preferred ones (Gormezano and Rockwell, 2013b). Bears foraging for land-based foods
have been reported empirically prior to recent concerns over climate change (Gormezano
and Rockwell 2013a). Observations of bears consuming garbage are not uncommon
(Gormezano and Rockwell 2013b) and bears are likely more aggressive at sites where
resources are defendable and predictable (Elfström et al. 2014), such as garbage dumps
and Inuit hunting caches, which might explain aggressive behaviour of bears near
communities. Participants also felt bears are no longer afraid of humans because of
habituation to scientific surveys and human activities, consistent with other community
reports (Keith 2005, Kotierk 2010) and scientific observations (Dyck 2006, Stirling and
Parkinson 2006, Andersen and Aars 2008). Habituation to human activities is not
unexpected, especially when food is rewarded (Keith 2005).
Participants further reported young males are more likely to enter communities,
showing some evidence for a sexual dimorphic life history, where males maximize
growth by exploiting high-quality food areas (remote areas avoiding humans) and
females prioritize offspring and avoid males (Elfström et al. 2014). Participants also
reported behavioural adaptations, where mothers teach young how to acquire food near
communities; this behavioural transmission from mother to offspring has been reported in
other bear species (Kaczensky et al. 2006, Madison 2008, Elfström et al. 2014). Thus,
polar bear characteristics reported by community members could reveal early changes in
population health and ecology; large solitary males near communities might indicate lack
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of accessible, high-quality habitats (Elfström et al. 2014).
5.5.3 Challenges and considerations for polar bear monitoring and
research methods
Across the surveyed communities, several participants criticized invasive mark-recapture
methods for their negative effects on polar bears. Loud vehicles (e.g., snowmobiles)
displacing polar bears from hunting areas have been reported scientifically (Andersen and
Aars 2008), which could lead to decreases in body condition and reproduction. Although
scientific studies have shown little evidence for mark-recapture and radio collaring
effects on indicators of body condition, reproduction, and survival in polar bears (Messier
2000, Thiemann et al. 2013, Rode et al. 2014), the impacts of handling on long-term
behaviour and human-bear interactions have not been reported. The inclusion of local
communities in monitoring research can shed light on effects of research practices that
might not be immediately recognizable through scientific methods. This has been
recognized and efforts to include local participation are already in place (Peacock et al.
2011, Vongraven and Peacock 2011). Participants in my work also reported declining
health and body condition, and abnormal behaviour attributable to radio collaring, as well
as increased aggression of bears that have been previously handled toward humans, thus
endangering local communities. Still, some community members believe mark-recapture
could provide important data on population dynamics to inform appropriate harvest
regulations, as long as surveys take into account temporal and spatial considerations for
representative sampling. Mark-recapture surveys in some regions occur in the spring
during den emergence and mating season to maximize probability of capture (Vongraven
and Peacock 2011, Rode et al. 2014) and interpretations of population viability analyses
have been discussed within the context of sampling biases due to bear movements and
reactions to helicopters (Taylor et al. 2006).
Each polar bear subpopulation is examined and studied every 10 to 15 years
(Peacock et al. 2011, Vongraven and Peacock 2011) and communities affected by this
work are usually involved from the initial planning stages (e.g., consultation meetings),
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through the research as participants, to reporting back to communities as a three to four
year process. In some cases, local community perspectives and TEK have been
documented to complement scientific studies (e.g., communities harvesting Baffin Bay
[Dowsley 2007], Davis Strait [Kotierk 2010], and Western Hudson Bay [Kotierk 2012]
populations). However, unless a community harvests from several populations, a
substantial time can pass until polar bear-related research occurs in the same community
again. This suggests that some of the research concerns that community members
reported to me might reflect research practices that are out of date, perhaps due to lack of
awareness or understanding of updated research methods in other areas (e.g., new less-
invasive aerial [Stapleton et al. 2014, Stapleton et al. 2016], genetic-based [Van
Coeverden de Groot et al. 2013] and biopsy-dart [Pagano et al. 2014] sampling methods
that have been developed as a response to community concerns) and accessibility to
contemporary scientific data in other regions (whether through scientific literature or
reports). Regional representatives of Inuit designated organizations, for example, regional
wildlife boards, must exchange relevant and updated information with their counterparts
from other regions, which must then be distilled to each community HTO. As there are
three regions spanning Nunavut—Kitikmeot, Kivalliq, and Qikiqtaaluk comprising five,
seven, and 13 communities, respectively—frequent exchange across this scale is certainly
challenging. However, through research participation and engagement with researchers,
community members could become aware of ongoing research in other regions.
Instances where participants do not support any scientific research practice are, in
some cases, associated with a misunderstanding of research goals, suggesting there is
room for improvement in communicating research objectives and expected outcomes
among management, research, and local communities. Despite concerns at the participant
level over insufficient reporting, some (academic and government) researchers do hold
consultation meetings on a frequent basis when conducting polar bear research, include
local communities in the field where possible, and report back to HTOs through written
translated reports, orally translated presentations, and discussions with translators present.
In all communities, scientific information (prepared by the Government of Nunavut) is
available through booklets distinguishing males and females (to encourage male-biased
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harvests) and posters explaining scientific surveys. HTOs are aware and acknowledge
these efforts, despite lack of awareness at the level of community members. This
indicates that even though efforts are in place to distil research processes and data to
relevant community organizations, community members—especially elders and
individuals that are not active in research and/or management participation—may not
necessarily receive or have access to this information; in other words, research is not
being delivered or communicated back in a way that communities desire and need.
Research reports should highlight themes that are relevant to community-specific
interests and priorities (e.g., implications for harvests and human-bear interactions) and
how these results can be used in monitoring and management and—most importantly—
benefitting Inuit. Because Inuit knowledge is often passed on through word of mouth
versus written reports, effort is needed to establish capacity for the diversity of
community members (e.g., youth, older elders) to learn about scientific information as it
relates to the community. This could be made possible by making research findings
accessible through presentations at the school, local organizations, community hall, radio
announcements, posters, videos, and websites that include contact information,
depending on the community. These efforts will require active HTO involvement and are
in most cases considered as falling beyond the scope of a typical scientist’s job
description. Aside from their own research priorities, academics and scientists working in
the north require skills in communications across cultural settings, consulting, program
management and supervision, hiring, mentorship, and financing, to name a few. These
efforts should be routine and are necessary to engage communities and keep community
members up to date with research projects and the broader contexts that they are a part of.
While these commitments could be challenging for “southern” researchers to meet—
especially with expensive northern travel and limited time available to spend up north—
this level of engagement for any research in the north is necessary from an ethical,
practical, and moral standpoint.
In some communities, mass turnover of community (HTO) staff might make it
difficult for community members to stay current with research processes. HTOs often
receive several (research and non-research related) reports at a time and other community
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priorities might take precedence over reading them. HTOs are not only involved in
research activities, they review proposals, technical reviews, economic development
plans, land plan use activities, harvesting issues, etc. These form a plethora of demanding
issues that at times cannot be accommodated. HTO boards are established on the basis of
knowledge experience, and the administrative duties and bureaucracy demanded of them
often lie beyond their capacity. Combined with the limited financial and timing capacity
of most researchers to remain up north to engage communities, these ongoing issues
suggest that polar bear research, and research in the north in general, might require
community-based research institutions and/or coordinators, where designated, active
liaisons bridge gaps in communication and engage communities in research projects.
Some of the barriers to communication might be due to poor interpretation by researchers
and community members, or the lack of technical understanding of ideas and scientific
information that is inadequately translated into local dialects (Inuktitut) and back to
English. Thus, interpreters (for both research conduct and preparation of reports) with a
comprehensive understanding of research contexts, data gathering and analysis, and
applications are necessary for this process. These issues touch on another endemic issue
that is education and beyond the scope of this discussion. Aside from these exigencies,
researchers are still responsible for the research process and adapting their research views
according to Inuit culture, context, language, and protocols that their research is a part of.
5.5.4 Concluding remarks for northern community-based research
Discussions on research relationships with and practices conducted by academic and
government organizations are not easily distinguishable, suggesting some community
members might generalize their research experiences to “outsiders” as a whole. Past
views and experiences still shape current community perspectives, and views against
academic and/or government research persist, especially when past research practices
have ignored or failed to incorporate community concerns. Communities differ in their
levels of research engagement and willingness to participate yet more time and effort can
ensure an understanding of research objectives, especially in communities that have
negative views toward all types of research due to past experiences with unethical
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conduct (e.g., inadequate consultations, disagreement with research practices, lack of
reporting back, and misrepresentation). Considerable time is needed to mend past
relations and experiences. For Inuit, local knowledge and perceptions are shaped by
social views that are fundamental to physical survival (Bennett et al. 2016). For
researchers, knowledge perceptions are usually research- and/or academic-focused and
not necessarily relevant to livelihood. Ethical research practices from the outset are
critical in setting the stage for all types of forthcoming research activities. Opportunities
to participate in research and decision-making processes need to be made transparent by
the researcher (Chilvers 2008), especially with respect to how outputs will be used to
direct policy (Rowe and Frewer 2000). Clarifying community and research roles and,
more importantly, research limitations and their impacts on communities can avoid
misconceptions.
Although all participants follow management regulations, each individual varies
in his or her level of familiarity with and support for current management and research
practices. Researchers should contact other researchers who have worked in the same
communities as well as local Hamlet, Arctic college, and relevant community
organizations to determine what forms of engagement do and do not work. Two-way
lines of communication between researchers and community members should be
maintained and accommodating for community members throughout all stages of
research (e.g., telephone or fax may be preferred over email). It will likely be necessary
to report back and check in on multiple occasions. This will require persistence on the
part of researchers and communities are likely to engage if research objectives speak to
community priorities. Lack of community engagement might suggest that research
outputs have failed to incorporate community needs. Research questions and efforts to
determine how communities could benefit from their participation might need to be re-
visited. As with any personal interaction, relationships should be maintained and nurtured
even after data gathering is complete.
Strong and transparent relationships between polar bear researchers and Inuit
communities are necessary to overcome persisting misconceptions in research and
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communities. For community members, most types of research have been viewed as
inseparable from government agendas through funding and consulting programs
(Bocking 2007) and past histories and power relations have politicized views of scientific
research as a whole (Reed and McIlveen 2006). Upon arrival into any community, a
researcher should take on the role of a learner, shifting from research driven by expertise
and certainty to one with humility and willingness to adapt to changes (Grimwood et al.
2012, Brunet et al. 2014b). As community participation in research projects will
undoubtedly impact research results and community members through potential to inform
management, forming collaborations in research design can guide research toward
community priorities so that these priorities are effectively included in subsequent
decision-making. In the past, academics have been criticized for prescribing expected
research plans and outcomes in a rigid way, leading to condescending views of unfamiliar
knowledge practices and unwelcoming interactions with community members
(Grimwood et al. 2012). Notwithstanding, community members also recognize the need
to strengthen communication and relationships to achieve a mutual understanding in open
collaborations. Ethical research conduct will pave the way for positive conceptions of
forthcoming research programs. In these contexts, the ability to build meaningful
relationships is not only critical for successful research involving TEK, but for sustaining
community involvement in research activities and support for research-based policies.
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Chapter 6
Synthesis of chapters and concluding discussion 6
6.1 Summary of chapters
In chapter 2, TRF assays were successfully developed to quantify telomere lengths in 21 wild
grizzly bears (seven females and 14 males). While effects of age and sex on telomere length
were significant and indicators of acute and oxidative stress were not significant, these findings
were based on small sample sizes and will require further investigation in larger groups.
However, TRF assays using fresh samples collected from wild animals are feasible in frequently
monitored grizzly bears associated with life-history data, which could potentially allow for
longitudinal studies to quantify telomere rates of change. These studies could incorporate
survival and capture characteristics in telomere models.
In chapter 3, qPCR assays using 40 salvaged polar bear heart, muscle, and skin tissues
collected by Inuit hunters were able to detect differences in telomere length among age groups,
sex, and populations. While differences in age and sex were only significant in muscle,
significant differences across five polar bear populations were detected using all tissues. Assays
of additional skin samples across age and sex groups could confirm age and sex differences for
applications in noninvasive surveys. At minimum, this work suggests differences in telomere
length across populations could reflect genetic and ecological stressors affecting biological
senescence.
In chapter 4, interviews with four Inuit communities across Nunavut revealed shared
methods of identifying polar bear sex, age, body size, and health and hunting selectivity relates
directly to personal experience and preferences. The ability to distinguish individual polar bears
is important not only for food, fur quality, and hide preparation, but also safety against
potentially aggressive bears. Inuit methods of identifying polar bear characteristics show some
overlap with conventional scientific methods, suggesting Inuit could provide frequent,
complementary information on polar bear populations.
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In chapter 5, interviews indicate that guidelines and ethics procedures for community-
based collaborative research in the north do not always guarantee meaningful collaborations.
Though efforts to report scientific information back to communities are in place, Inuit still
continue to meet polar bear research with some resistance. Strong relationships with Inuit
communities are necessary to establish and maintain community capacity in monitoring, as well
as encourage relevance for research outputs and, thus, support for resulting management
decisions.
6.2 Telomeres as an indicator of biological senescence
While TRF assays could potentially detect age- and sex-specific differences in telomere length in
wild grizzly bears, qPCR was more practical for detecting these patterns in wild polar bears.
Quantitative PCR was also able to show differences in telomere length among populations.
Differences in telomere length could reflect differences in ecology (Thiemann et al. 2008a) and
biology (Derocher and Stirling 1998), as well as responses to local genetic (Cronin et al. 2009,
Zeyl et al. 2009, Peacock et al. 2015) and environmental stressors (Stirling and Parkinson 2006,
Peacock et al. 2011). Rapid changes in sea ice conditions (Regher et al. 2007), prey availability
and composition (Thiemann et al. 2008a), hunting pressures, and interactions with humans
(Dowsley 2009) could elicit stress responses that lead to physiological damage and thus, aging
phenotypes (Cadenas and Davies 2000, Monaghan et al. 2008, Macbeth et al. 2010, Beaulieu
and Constantini 2014). In this manner, it is likely that telomere lengths will serve as a more
appropriate marker of biological senescence, versus chronological aging. Understanding how
environmental and physiological stressors mediate population characteristics (e.g., age and sex
structure, body condition) is necessary for appropriate management actions. Prolonged exposure
to physiological, oxidative stress responses could compromise survival and reproductive output
(Macbeth et al. 2010, Beaulieu and Constantini 2014), and hence population abundance.
Because several interacting physiological, ecological and environmental factors could
impact telomere dynamics, they should be considered in any model for telomeric aging. One
such variable is body size, which varies across polar bear populations (Derocher and Stirling
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1998), and is indicative of body condition and survival (Stirling and Parkinson 2006, Regehr et
al. 2007, Stirling et al. 2010), as well as reproductive output (Derocher and Stirling 1996). Body
size has been shown to shorten telomeres and contribute to aging in wild house sparrows
(Ringsby et al. 2015) and American alligators (Scott et al. 2006). Telomere rates of change
(attrition) could also vary with chronological age (Frenck et al. 1998, Hall et al. 2004, Pauli et al.
2011), with higher rates of shortening in early life due to rapid cell and energy turnover (Sidorov
et al. 2004) and stress during maturation to adulthood (Hall et al. 2004, Salomons et al. 2009).
Chapter 4 showed some support for this, where Inuit indicated that polar bears achieve adult
sizes fairly quickly. Telomere attrition may also vary according to differences in telomerase
activity across tissues (Eisenberg 2010, Monaghan 2010). Though rare, telomerase activity in
somatic tissues could be quantified in cell culture (e.g., Gomes et al. 2011) or directly from
tissues (e.g., Jacobs et al. 2010, Lin et al. 2010). Tissue-specific attrition rates could also be
estimated in vivo by re-sampling the same wild or captive individuals across time, confirming
identity through microsatellite genotyping (Van Coeverden de Groot et al. 2013) or breeding
records, respectively. Such longitudinal studies could also allow for changes in somatic
functioning and individual survival to be observed. Heritability and relatedness may also affect
telomere patterns and attrition; evidence for this has been shown in humans, where longer
telomeres have been observed in the offspring of older fathers (Monaghan 2010, Eisenberg
2010). Heritability and relatedness in wild polar bears could be determined through
microsatellite genotyping (van Coeverden de Groot et al. 2013). Maternity and paternity have
been previously estimated for M’Clintock Channel and Gulf of Boothia polar bears (Saunders
2005) and efforts to improve these estimates through the addition of more loci are ongoing. Both
populations are also currently being re-sampled through mark-recapture (Government of
Nunavut 2015).
By examining wild polar bear populations, this research contributes to a better
understanding of polar bear senescence in vivo, as very few wild animals live long enough to
suffer senescent declines (Monaghan et al. 2008). This work also suggests qPCR assays for
telomere length could be applied to skin and, thus, similar noninvasive samples (e.g., biopsy
darts and/or hair samples). Prior to noninvasive survey applications, qPCR assays in a larger
sample of known skin samples that capture variation in age and sex within populations,
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especially females and cubs, will be required to characterize telomere lengths as they relate to
these groups. Noninvasive samples could be genetically sexed, genotyped and cross-referenced
with mark-recapture data to incorporate known age, sex, and additional body condition indices
(Taylor et al. 2006a, Van Coeverden de Groot et al. 2013) to evaluate their effects on telomere
dynamics in these samples. Hair cortisol concentration could also be measured in hair samples
(Beschøft et al. 2011) to include indices of stress. Once developed, telomere assays in
noninvasive samples could be linked to Inuit interpretations of tracks (Wong et al. 2011) to
incorporate information on bear characteristics, morphology, behaviour. For harvested polar
bears, supplementing biological data from harvested samples with Inuit hunter knowledge of
health, body condition, and population changes could reveal factors associated with individual
polar bears and samples that are not detectable using scientific methods. Interviews with
communities could also reveal drivers of hunter selection—for example, management
regulations, personal preferences, or logistical constraints leading to biases in harvests—to
determine how representative samples and thus telomere assays are to polar bear populations and
species as a whole. For survey and monitoring applications, telomere assays will require the
same assay procedures and protocols for quantification to be conducted in the same lab to
minimize inter-assay (multi-year monitoring) variation (Nakagawa et al. 2004, Horn et al. 2010,
Aviv et al. 2011, Dunshea et al. 2011, Nussey et al. 2014).
For polar bears, quantifying DNA methylation in known age-related epigenetic markers
could serve as an alternative molecular method to telomeric aging. In mammals, DNA
methylation involves the addition of a methyl group to the 5-carbon of the cytosine ring of a
CpG dinucleotide (cytosine followed by a gunanine base; Calvanese et al. 2009, Jung et al. 2015,
Zampieri et al. 2015). CpG sites are largely focused in promoter regions and repeat sites, where
methylation usually silences gene expression and/or maintains genome integrity (Calvanese et al.
2009, Jung et al. 2015, Zampieri et al. 2015). In response to environmental factors and stochastic
errors in transmitting epigenetic information over time (Zampieri et al. 2015), changes in
methylation of CpG sites with age (hypomethylation and hypermethylation) have been observed
in human blood (Fuke et al. 2004, Bjornsson et al. 2008), muscle (Zykovich et al. 2014), and
skin (Grönniger et al. 2010) and a range of mouse tissues (Wilson et al. 1987). Recently, the
effect of age on percent CpG methylation in several known age-related epigenetic markers was
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observed in humpback whale biopsy tissues (Polanowski et al. 2014). These assays have not
been conducted in ursids and, as with telomeric aging, will need to take into account potential
confounding factors, such as environmental variation (Polanowski et al. 2014, Jung et al. 2015).
At a broad scale, for any study examining age in wild animals, sampling across age
categories in age-structured populations could be biased due to the inherently low number of
individuals in older age classes (Wilson et al. 2008, Nussey et al. 2008). For telomeric aging,
sampling could also be biased if polar bears are associated with selective disappearance of
particular telomere lengths or telomere attrition rates that are cohort-specific (Monaghan 2010,
Mather et al. 2010, Eisenberg 2010). For example, critically short telomeres may not be observed
because individuals with very short telomeres die off, perhaps due to extrinsic mortality risks.
These biases could potentially limit adequate sampling across all age categories. Biases in
harvests toward large, adult males due to management regulations and hunting preferences also
limit adequate harvest sampling of cubs and females within populations. Across populations,
harvest quotas differ (e.g., from three animals in M’Clintock Channel to 61 in Davis Strait;
Government of Nunavut 2014-2015 Harvest Report), which limit equal distributions of harvest
samples across all populations. For populations with small quotas, larger sample sizes could be
achieved through noninvasive sampling led by Inuit hunters (Van Coeverden de Groot et al.
2013), where cubs and females could be sampled by targeting denning areas in the spring after
emergence.
6.3 Inuit methods of estimating polar bear health as potential
indicators of biological senescence
For Inuit, identifying indicators of biological senescence (health), chronological age and sex in
polar bears is important not only to follow harvest management regulations, but also govern and
interact with a resource according to traditional ethics and values. Inuit observe body size and/or
fat, fur color and quality, and bear movements and behaviour as indicators of polar bear health.
In Arviat, Inuit usually identify health of polar bears that they encounter, as health has direct
implications for aggressiveness and, thus, human safety. Inuit prefer to pursue healthy bears
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when hunting, especially for food and hides, which are of higher quality in healthy bears.
According to Inuit, polar bear health is impacted by factors that contribute to stress, including
hunting ability. Stress contributes to biological senescence through the accumulation of
damaging reactive oxygen species produced as a by-product of stress responses (Macbeth et al.
2010, Beaulieu and Constantini 2014). However, in instances where food is not available, stress
responses can mobilize energy toward increased foraging effort (Romero 2004). Similarly, Inuit
indicate changes in prey availability impact health; in Chapter 3, telomere lengths among
populations corresponded to levels of prey diversity, with shortest mean length in a population
with low prey diversity (Thiemann et al. 2008a). Inuit also indicate male-to-male combat
impacts health, and unhealthy bears are more aggressive toward humans. It is likely that
aggression is associated with elevated stress hormones (Goyman and Wingfield 2004), which
could contribute to telomere shortening (Epel et al. 2004, Haussmann et al. 2012). Inuit also
report younger bears are more active and aggressive toward humans, suggesting age and stress
could interact to affect biological senescence. Indeed, Inuit are likely aware of methods and
indicators of biological senescence in polar bears and their knowledge could inform—and in
some cases overlaps with—scientific approaches to gathering these data. However, the type of
information that government and academic scientists seek is also affecting Inuit knowledge
formation within the context of how Inuit interact with or understand polar bears. For example,
Inuit identify ages and body sizes of bears to protect cubs during harvests though, historically,
only body sizes were of interest (Chapter 4). Some Inuit examine teeth to age polar bears, which
is likely due to experience with estimating age for harvest monitoring records. When engaging
with Inuit communities, researchers must consider the dynamic nature of Inuit qaujimajatuqangit
that is actively shaped by the social, cultural, and ecological systems within which it is
embedded.
6.4 Conclusions
The interviews in this work suggest Inuit consider several observations at the same time to
distinguish age, sex, and body size and health in polar bears. This approach to examining polar
bear characteristics and biological senescence could certainly be paralleled using scientific
methods, where multiple factors are considered simultaneously to model telomere dynamics. For
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conservation applications of polar bear research—and all types of research in the north—long-
term relationships with Inuit communities will be necessary not only to acquire biological
samples and document traditional ecological knowledge, but also to ensure relevance and
meaning of scientific outputs for communities. Inuit communities interact with animals as part of
their livelihood and are likely able to suggest and/or inform research methods that are of
conservation relevance. Further, Inuit interpretations of scientific information distilled in a
comprehensive manner could allow for more effective integration of traditional ecological
knowledge and Inuit qaujimajatuqangit in northern co-management. For scientists, a better
understanding of Inuit knowledge formation and the cultural, ecological, and social processes
that Inuit persist in will likely allow for more meaningful and responsible methods of research
collaborations and co-management.
This research demonstrates that the direct participation of Inuit hunters in collecting
samples for scientific research could allow for physiological investigations of ecological and
environmental factors that impact biological senescence in polar bears, which would otherwise
not be possible. Using telomeres as an indicator biological senescence, TRF assays could be used
in frequently monitored animals that provide fresh, high quality samples, while qPCR assays are
useful in noninvasive samples and animals where collecting high quantities and qualities of
genomic material is difficult. For polar bears, scientific interpretations of ecological data could
be enriched through the inclusion of Inuit knowledge of population characteristics and indicators
of biological senescence. Inuit continue to support the inclusion of traditional knowledge in
developing scientific methods to achieve common conservation objectives. Still, efforts are
needed to establish and maintain strong relationships. The inclusion of Inuit in polar bear
research, monitoring, and management will continue to identify linkages between two
independent (scientific and traditional) knowledge types in co-managing potential species at risk.
175
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