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Northern Leopard Frog Reintroduction Strategy for Alberta
CONSERVATIONCONSERVATION
REPORT REPORT
SERIESSERIES
CONSERVATIONCONSERVATION
REPORT REPORT
SERIESSERIES 25% Post Consumer FibreWhen separated, both the binding and paper in this document are recyclable
The Alberta Conservation Association is a Delegated Administrative Organization under Alberta’s Wildlife Act.
Northern Leopard Frog Reintroduction Strategy for Alberta
Kris Kendell1 and Dave Prescott2 1 Alberta Conservation Association
101 ‐ 9 Chippewa Road Sherwood Park, Alberta, Canada T8A 6J7
2 Alberta Sustainable Resource Development Fish and Wildlife Division, #404 ‐ 4911 51 Street
Red Deer, Alberta, Canada T4N 6V4
Report Series Editor PETER AKU KELLEY J. KISSNER Alberta Conservation Association 59 Hidden Green NW #101, 9 Chippewa Rd Calgary, AB T3A 5K6 Sherwood Park, AB T8A 6J7 Conservation Report Series Type Data, Technical ISBN printed: 978‐0‐7785‐6549‐9 ISBN online: 978‐0‐7785‐6550‐5 Publication No.: T/156 Disclaimer: This document is an independent report prepared by the Alberta Conservation Association. The authors are solely responsible for the interpretations of data and statements made within this report. Reproduction and Availability: This report and its contents may be reproduced in whole, or in part, provided that this title page is included with such reproduction and/or appropriate acknowledgements are provided to the authors and sponsors of this project. Suggested Citation: Kendell, K., and D. Prescott. 2007. Northern leopard frog reintroduction strategy for
Alberta. Technical Report, T‐2007‐002, produced by Alberta Conservation Association, Edmonton, Alberta, Canada. 31 pp + App.
Cover photo credit: David Fairless Digital copies of conservation reports can be obtained from: Alberta Conservation Association #101, 9 Chippewa Rd Sherwood Park, AB T8A 6J7 Toll Free: 1‐877‐969‐9091 Tel: (780) 410‐1998 Fax: (780) 464‐0990 Email: info@ab‐conservation.com Website: www.ab‐conservation.com
i
EXECUTIVE SUMMARY
The northern leopard frog (Rana pipiens) has suffered dramatic population declines in
many parts of its range in Alberta that have resulted in fragmented populations that are
separated by large expanses of unsuitable habitat. As a result, the northern leopard
frog is severely limited in its recolonization potential in Alberta. The reduced area of
occupancy and fragmented populations have led to the species being listed as
Threatened under Alberta’s Wildlife Act, first in 1996, and reaffirmed in 2003.
Consequently, in 2004, the Minister of Sustainable Resource Development established
the Alberta Northern Leopard Frog Recovery Team (ANLFRT), which drafted a
recovery plan, the Alberta Northern Leopard Frog Recovery Plan (ANLFRP) that was
approved by the Minister in 2005. The ANLFRP describes strategies and actions
necessary for achieving the provincial goal of a “well‐distributed, self‐sustaining
population of northern leopard frogs throughout their historical range in Alberta”.
Several reintroductions have been attempted in the past to reestablish the northern
leopard frog in select areas of the province. These attempts were met with only limited
success; however at one site, a self‐sustaining northern leopard frog population was
achieved. Not withstanding, reintroduction was identified by the ANLFRP as a key
strategy to overcome the improbable natural recolonization for the northern leopard
frog in Alberta. The ANLFRT believes that the recovery of the northern leopard frog in
Alberta is achievable, but also recognizes that reintroduction is a complex process. This
document details the methodologies required to maximize the probability of successful
reintroductions of northern leopard frogs into vacant historical habitats in Alberta. The
information herein provides guidelines that are based on the best available expert
opinion and knowledge acquired through previous reintroduction attempts for the
species in Alberta and other jurisdictions. This document discusses issues that must be
considered while conducting reintroductions, such as the selection of priority
watersheds and sub‐watersheds, choice of life stage to relocate, selection of source sites,
characteristics of relocation sites, the reintroduction process (i.e., translocations of
animals), monitoring activities and schedule, and assessment of success.
The ANLFRT reintroduction strategy is a living document, and as such, will be
evaluated in 2008 and refined as necessary.
ii
ACKNOWLEDGEMENTS The authors thank the following individuals for their input into this document and
editorial comments: Doug Adama (Adama Consulting ‐ Chair of British Columbia
Northern Leopard Frog Recovery Team), Brian Eaton (Alberta Research Council), Ed
Hofman and Scott Stevens (Alberta Fish and Wildlife Division), Janene Lichtenberg
(Confederated Salish and Kootenai Tribes), Cindy Paszkowski and Greg Wilson
(University of Alberta), Peter Aku, Sue Peters, and Amanda Rezansoff (Alberta
Conservation Association), Cyndi Smith (Parks Canada), Tony Russell (University of
Calgary), and Doug Whiteside (Calgary Zoo).
iii
TABLE OF CONTENTS
EXECUTIVE SUMMARY.......................................................................................................... ii
ACKNOWLEDGEMENTS....................................................................................................... iii
TABLE OF CONTENTS ........................................................................................................... iv
LIST OF FIGURES...................................................................................................................... v
LIST OF APPENDICES ............................................................................................................ vi
1.0 INTRODUCTION ............................................................................................................1 1.1 Past reintroduction activities ..........................................................................................3
2.0 REINTRODUCTION STRATEGY .................................................................................5 2.1 Genetic and disease considerations...............................................................................6 2.2 Selection of priority watersheds and sub‐watersheds ................................................8 2.3 Choice of life stage for translocation ...........................................................................11 2.4 Selection of source sites .................................................................................................12 2.5 Characteristics of relocation sites.................................................................................14
3.0 REINTRODUCTION PROCESS...................................................................................15 3.1 Collection of egg masses, eggs, and hatchling tadpoles...........................................15 3.2 Transportation of egg masses, eggs or hatchling tadpoles to recipient site ..........18 3.3 Handling of egg masses, eggs or hatchling tadpoles at recipient site ....................18 3.4 Egg and hatchling tadpole monitoring schedule.......................................................20 3.5 Release of tadpoles at recipient site .............................................................................20
4.0 MONITORING ACTIVITIES AND SCHEDULE.......................................................22 4.1 Year one (first year of egg translocation)....................................................................22 4.2 Year two (second year of egg translocation) ..............................................................22 4.3 Year three ........................................................................................................................22 4.4 Five‐year inventory cycle ..............................................................................................23
5.0 ASSESSMENT OF SUCCESS........................................................................................23 5.1 Initial success ..................................................................................................................23 5.2 Intermediate success (year one and two)....................................................................23 5.3 Complete success (year three) ......................................................................................23
6.0 LITERATURE CITED ....................................................................................................25
7.0 APPENDIX......................................................................................................................32
iv
LIST OF FIGURES
Figure 1. Present range of the of the northern leopard frog in southern Alberta .......... 2
Figure 2. Major watersheds currently and historically occupied by northern leopard frogs.. ........................................................................................................................ 9
Figure 3. Precedence for the reintroduction of frogs will be given to areas noted as A‐E, where northern leopard frog populations have suffered the severest declines and where suitable habitat is believed to occur................................ 10
Figure 4. An egg mass predator exclosure basket.. .......................................................... 17
v
vi
LIST OF APPENDICES
Appendix 1. Northern leopard frog release site suitability checklist. ....................... 32
CONSERVATIONCONSERVATIONREPORT REPORT SERIESSERIES
1.0 INTRODUCTION
The northern leopard frog (Rana pipiens) was once a common species in southern
Alberta. However, dramatic population declines in many parts of its range occurred in
the late 1970s and early 1980s (Roberts 1981, 1987). These declines, along with
reductions in suitable habitat and fragmentation of populations, led to the species being
listed as Threatened under Alberta’s Wildlife Act, first in 1996, and reaffirmed in 2003
(Alberta Environmental Protection 1996; Alberta Northern Leopard Frog Recovery
Team 2005). Pursuant to these listings was the formation of the Alberta Northern
Leopard Frog Recovery Team (ANLFRT), which drafted a provincial recovery plan, the
Alberta Northern Leopard Frog Recovery Plan (ANLFRP) that received ministerial
approval in 2005.
The 2005 – 2010 ANLFRP describes strategies and actions necessary for achieving the
provincial goal of a “well‐distributed, self‐sustaining population of northern leopard
frogs throughout their historical range in Alberta” (ANLFRT 2005). The small and
fragmented nature of current populations (see Figure 1), in conjunction with large
expanses of arid upland, reduction of suitable dispersal corridors, and degradation of
other important habitats that support long‐distance movements, severely limit
dispersal and recolonization opportunities of the northern leopard frog in Alberta
(Alberta Sustainable Resource Development 2003; ANLFRT 2005). The provincial
recovery plan aims to reintroduce northern leopard frogs to a least 10 sites within their
historical range in southern Alberta by 2010 (ANLFRT 2005).
1
Figure 1. Present range of the of the northern leopard frog in southern Alberta. Data
are from a survey conducted in 2005 (Kendell et al. 2007). Size of dots indicates relative size of adult and sub‐adult frog populations during the survey, expressed as number of frogs per person‐hour of survey effort.
2
The practice of translocation of species into areas where they are currently extirpated is
an accepted component of conservation‐oriented management programs for threatened
and endangered species (Fisher 1999). In Alberta, the translocation of northern leopard
frogs will ultimately help increase the overall provincial population. Further, an
increase in the number of extant populations will help to alleviate concerns associated
with current populations, such as vulnerability to disease and human disturbance, as
well as susceptibility to climatic and demographic fluctuations. Threats and limiting
factors responsible for the original decline of the northern leopard frog are not well
understood (ANLFRT 2005). Therefore, the ANLFRT has recognized that successful
reintroductions may not be guaranteed, as habitats and populations may continue to be
affected by undetectable, obscure or intermittent factors that first caused extirpation.
Nonetheless, the ANLFRT considers that reestablishment of northern leopard frogs into
their historical range is biologically and technically feasible, largely owing to increased
understanding of the biology and ecology of the species.
This document defines the methodologies related to the reintroduction of northern
leopard frogs in Alberta. The information herein is based on the best available
knowledge (published and expert opinion), including up‐to‐date information on the
distribution and relative size of frog populations in Alberta (see Figure 1). It is our
intention to apply knowledge acquired from previous successes and failures at
reintroduction, and to use those procedures that maximize the probability of successful
reintroductions. Unless otherwise stated, tadpole development stages follow
designations in Gosner (1960).
1.1 Past reintroduction activities
Several reintroductions have been attempted to reestablish the northern leopard frog in
select areas of the province. Two reintroduction attempts in the 1980s involved
informal releases of northern leopard frogs at two undisclosed sites in the Pine Lake
region of central Alberta (Roberts 1991, 1992). It has been reported that the
reintroduction attempt failed at one site because of a winterkill event that eliminated
the population (Fisher 1999). There is no information available as to the status of the
population at the second site.
3
In 1998, the Alberta Fish and Wildlife Division (AFWD) explored the feasibility of
reintroducing northern leopard frogs into formerly occupied habitats (Fisher 1999). In
1999, the Alberta Conservation Association (ACA) and AFWD initiated a pilot
reintroduction project at the Raven Brood Trout Station near Caroline, Alberta
(Wendlandt and Takats 1999). The project involved the captive rearing of northern
leopard frogs, from eggs (collected in southern Alberta) to metamorphosed frogs, in
two large outdoor ponds at the Raven Brood Trout Station.
The release of young‐of‐year (YOY) northern leopard frogs occurred at three pilot sites
from 1999 to 2004: the Raven River near Caroline in 1999, a North Saskatchewan River
site near Rocky Mountain House in 2001, and a Ducks Unlimited project near Red Deer,
Alberta in 2002. In total, nearly 14,000 YOY were released into these sites (Kendell
2001, 2002a, 2004a, 2004b; Wendlandt and Takats 1999). Initial evidence suggested that
reintroduction efforts at the Raven River release site were successful; at least 10 frogs
released in previous years were located within this study area in 2001, and confirmed
frog observations followed each year, up until and including 2004 (Kendell 2001,
2004a). In addition, evidence of breeding activity was observed in 2002, including the
detection of calling male frogs and the discovery of one viable egg mass (Kendell
2002a). However, no frogs were observed at the Caroline site during monitoring in
2005 and 2006. There have been no confirmed northern leopard frog observations from
the North Saskatchewan River site or the Ducks Unlimited property, despite
monitoring efforts (Kendell 2004a; Kendell et al. 2007).
Alberta Fish and Wildlife Division initiated the Magrath northern leopard frog
reintroduction project in spring 2002. The goal of the project was to reestablish a
breeding population of northern leopard frogs in formerly occupied habitat in the
Magrath area (Romanchuk and Quinlan 2006). The primary rearing site was a water
body known as Dudley’s Pond, situated near Pothole Creek at the southwest edge of
Magrath, Alberta. During the course of the three‐year project, egg masses were
collected from one of three different source ponds in 2003, 2004 and 2005 (Medicine
Hat’s Strathcona Island Park, Bull Springs area and Red Creek area, respectively). In
total, approximately 8,500 eggs were released into Dudley’s Pond and at a site
approximately 0.6 km upstream of the pond, along Pothole Creek. These egg mass
releases have resulted in a self‐sustaining northern leopard frog population in Magrath.
4
Primary evidence to support this includes the observation of a large number of YOY
frogs in July 2005 and July 2006, which indicates that natural reproduction took place in
Dudley’s Pond or adjacent habitats along Pothole Creek (Romanchuk and Quinlan
2006).
Additional reintroduction projects have recently been undertaken in the Pacific
Northwest, particularly in British Columbia (Waye and Cooper 2001; Wind 2002) and
Montana (U.S. Department of the Interior 2002). Before 1980, northern leopard frogs
were known to occur in at least a dozen sites in British Columbia; by the early 1990s
they were considered extirpated. However, in 1996 a single population was found in
the Creston Valley Wildlife Management Area (CVWMA). Between 2001 and 2005, the
Columbia Basin Fish and Wildlife Compensation Program (CBFWCP), in cooperation
with the British Columbia northern leopard frog recovery team, have head‐started and
captive‐reared tadpoles for reintroduction as well as augmentation at a remnant source
site (Adama et al. 2003, 2004; D. Adama pers. comm.).
The northern leopard frog was once common throughout Montana but now is absent
from portions of the state west of the Continental Divide. The Confederated Salish and
Kootenai Tribeʹs Wildlife Management Program has been working to reestablish
northern leopard frogs in the Flathead Indian Reservation following a complete
extirpation of the species in the 1980s. Between 2003 and 2005, eggs were collected
from five source populations east of the Continental Divide. Tadpoles were reared
from eggs to more advanced stages of development in enclosures, and a proportion of
the tadpoles were released at two sites. In 2006, frogs were observed at both
reintroduction sites, indicating preliminary success in the reestablishment of frogs at
the two sites (J. Lichtenberg pers. comm.).
2.0 REINTRODUCTION STRATEGY
Reintroduction of northern leopard frogs into vacant areas of its range is a complex
process and should be conducted in a manner that poses minimum threats to source
populations while maximizing the probability of success of the introduced population.
Constraints such as funding, manpower, and local land use practices dictate that
5
priorities be established in terms of where the reintroduction program will be
delivered. The following topics are addressed as part of this strategy:
• Genetic and disease considerations
• Selection of priority watersheds and sub‐watersheds
• Choice of life stage to relocate
• Selection of source sites
• Characteristics of relocation sites
• Reintroduction process
• Monitoring activities and schedule
• Assessment of success
2.1 Genetic and disease considerations
The reintroduction of populations through human intervention inevitably involves the
possibility of moving poorly adapted individuals to new environments, especially if
those individuals are collected from areas with different environmental and habitat
conditions. Furthermore, relocated individuals could introduce diseases where they
were previously absent. These factors could reduce the probability of successful
reintroduction and might have negative effects on other amphibian species at release
sites.
In 2004, the ACA initiated a research project to investigate genetic diversity of northern
leopard frogs in Alberta. This investigation began with the collection of tissue samples
from selected northern leopard frog populations. Analysis of samples will be
completed in partnership with the University of Alberta in early 2008, and it is expected
that these data will determine the degree of genetic variation within and among
northern leopard frog populations in Alberta (G. Wilson pers. comm.). This
information will minimize the risk of translocating genetically maladapted individuals
to a recipient site. Pending results of the genetic study, the ANLFRT has stated that all
translocations be done over short distances and within the same watershed.
Short‐distance within‐watershed translocations will also help minimize disease
transmission to other amphibian species. Several organisms are known to cause
6
infectious diseases in amphibians, including: Batrachochytrium dendrobatidis (often
referred to as chytrid fungus) (Blaustein et al. 1994; Berger et al. 1998; Pessier et al. 1999;
Blaustein and Kiesecker 2002; McCallum 2005; Bosch and Solano 2006); Aeromonas
hydrophilia (commonly known as “red leg disease”) (Hird et al. 1983); ranaviral disease
(Greer et al. 2005); and Saprolegnia (Holt 1994).
Strategies in this document that deal with disease issues focus on the prevention of
introduction and spread of disease between reintroduction source and recipient sites.
Prevention of introduction and of spread of disease will be achieved through cleaning
and disinfection of field equipment that come into contact with individual frogs, and
between waterbodies that are isolated from one another. The process of cleaning and
disinfecting equipment should begin with the physical removal of organic debris (e.g.,
mud and vegetation), followed by the application of a 10% chlorine (household) bleach‐
to‐water solution that is thoroughly and generously applied over equipment using a
large spray bottle (commonly used to mist house plants). The bleach solution should be
allowed to sit for at least 10 minutes on equipment being sterilized and should be
rinsed thoroughly if the intended equipment is to come into contact with amphibians.
Strict procedures, as outlined by the Canadian Cooperative Wildlife Health Centre
Wildlife Disease Investigation Manual and as outlined by Kendell (2002b), will be
followed by field workers to prevent inadvertent transmission of any disease organism
within and between frog sites.
Prior to removal of frogs from their source site, disease surveillance will be conducted
at both the release and source site. At least 60 ‐ 100 individual northern leopard frogs,
or other anuran species, will be collected from potential source and recipient sites and
tested for disease through swabs and blood sample collection for PCR
(chytridiomycosis, ranavirus) (see Whiteside et al. 2007). All collected material will be
forwarded to the Animal Health Branch, Ministry of Agriculture and Lands,
Abbotsford, British Columbia for molecular diagnostics.
Amphibians that are encountered during reintroduction activities, including
monitoring activities, that are suspected to have disease (e.g., chytridiomycosis,
ranaviral disease, saprolegniasis), have deformities, or exhibit unusual behaviour, will
be collected and submitted for diagnostic testing and complete post‐mortem
7
examination at the Calgary Zoo Animal Health Centre, in Calgary, Alberta. Collected
tissues and samples will then be forwarded to the Animal Health Branch, Ministry of
Agriculture and Lands, Abbotsford, British Columbia for histopathology, ancillary
testing, and molecular diagnostics. Dead, moribund or diseased frogs, or other
amphibians, will also be collected for analysis and submitted to the laboratories noted.
2.2 Selection of priority watersheds and sub‐watersheds
The northern leopard frog historically occurred in all major watersheds in southern and
central Alberta (Milk, Oldman, Lower South Saskatchewan, Bow, Red Deer, Sounding
Creek, Battle River, and North Saskatchewan) (Figure 2), as well as, in two watersheds
in the extreme northeast (Slave and Lake Athabasca) (ASRD 2003). However, recent
surveys indicate that frogs are currently absent from the North Saskatchewan, Battle
and Sounding Creek watersheds and appear relatively rare in the Oldman and Red
Deer watersheds (Kendell 2002c; Kendell et al. 2007). Although it is a stated objective of
the ANLFRP that frogs be reintroduced into all historical watersheds (ANLFRT 2005),
the current prohibition on inter‐basin transfer of frogs precludes consideration of
reintroduction into these watersheds until either: (1) source populations within the
watersheds are discovered; or (2) completion of the genetic analysis suggests that
reintroductions from other watersheds is acceptable.
8
N
Figure 2. Major watersheds currently and historically occupied by northern leopard frogs. Watershed designations follow Alberta Environment (Government of Alberta 2006).
The status of northern leopard frog populations in the Slave River and Lake Athabasca
watersheds is unclear, but the species appears to be relatively widespread, and extant
populations face few obvious threats in the area (Kendell et al. 2007). The absence of
obvious threats, combined with the logistical difficulties of conducting a reintroduction
program in such a remote area, supports the exclusion of these watersheds from the
program. Of the five remaining watersheds, the ANLFRT considers the Oldman and
Red Deer watersheds to be the highest priority for reintroductions because of the
apparent loss of many populations from these areas, the proximity to healthy source
populations in the same watershed, and logistical considerations (Kendell 2002c;
Kendell et al. 2007). Secondary priority will be given to the Bow watershed, where the
middle and upper reaches have become depopulated in recent years. Populations in
9
the lower South Saskatchewan watershed are the most robust in the province, and will
not be targeted for reintroduction unless declines become evident. The Milk River
watershed, traditionally a well‐populated area, had surprisingly low populations in
2005, possibly as a result of extensive flooding in early summer (Kendell et al. 2007).
However, unless longer‐term population declines become evident, this watershed will
not be considered for reintroduction.
Within each priority watershed, precedence for the reintroduction of frogs will be given
to areas where populations have suffered the severest declines, and where suitable
habitat is believed to occur (Figure 3). In the Oldman watershed, this includes the
Waterton River sub‐watershed (area E) and the Little Bow River sub‐watershed (area
D). In the Red Deer watershed, priority will be given to the Berry Creek sub‐watershed
(area B) and the tributaries that drain into the main‐stem river near Drumheller
(Kneehills, Threehills and Ghostpine creeks; area A). Efforts in the Bow watershed will
focus in the sub‐watershed that extends between Calgary and Bassano (area C) (Figure
3).
Figure 3. Precedence for the reintroduction of frogs will be given to areas noted as A‐
E, where northern leopard frog populations have suffered the severest declines and where suitable habitat is believed to occur.
10
2.3 Choice of life stage for translocation
The ANLFRT advocates the use of eggs as the preferred life stage for translocation and
reintroduction for several reasons. First, eggs are often conveniently available and
easily collected, and each egg mass contains a large number of eggs, e.g., up to 7000
eggs per mass for northern leopard frogs (Corn and Livo 1989). Portions of several egg
masses can be collected to increase genetic diversity at reintroduction sites and to
maintain diversity at source sites.
Limiting the collection to eggs or hatchling tadpoles will also decrease the chances of
transmitting B. dendrobatidis. This fungus only occurs in keratinized epithelium of
amphibians and therefore is absent from eggs, and early tadpole stages (stages 24 ‐ 25
or less) that have not yet developed keratinized teeth and jaw sheaths (Commonwealth
of Australia 2006).
In addition, it is believed that the majority of young frogs will return to their natal
(hatching) site upon reaching reproductive maturity as amphibians are often
characterized as having strong site fidelity (Waye and Cooper 2001; Smith and Green
2005; D. Adama pers. comm.). This site fidelity will result in philopatry to the
reintroduction site.
Adults and sub‐adults are not preferred for translocation because they often occur only
in small numbers and can be difficult to locate and capture. They are also philopatric to
breeding and over‐wintering sites (Dole 1968) and thus may experience high mortality
as they become disoriented at an unfamiliar translocation site. Finally, the removal of
reproductively mature adults from a source site may have significant effects on
recruitment at that site, while the removal of a portion of egg masses or hatchling
tadpoles should have less effect.
Estimates of optimal number of eggs to be released per year and the number of years
necessary to establish a viable population is based on the results from the Magrath
reintroduction project (Romanchuk and Quinlan 2006). The reintroduction strategy
outlined in this document is dependent on the number of eggs available for collection
11
and release within the priority watersheds. It is proposed that the equivalent of a
minimum of two egg masses (approximately 4000 eggs per mass) be release at each site
over two consecutive years. Ideally, two egg masses should be introduced to at least
three breeding sites that are spatially arranged to allow for dispersal of metamorphosed
frogs, each year (see Tischendorf 2007).
Although eggs are the preferred life stage for translocation, researchers may fail to
locate eggs before they begin to hatch because of the unpredictable breeding behaviour
of northern leopard frogs. In such cases, newly hatched and relatively immobile
tadpoles (i.e., hatchling tadpoles or tadpole stage
Ideally, specific breeding ponds and egg mass deposition sites should be identified in
advance, so that eggs can be collected early in the spring. In addition, to ensure that
source sites have similar water chemistry and quality as the intended recipient sites, a
variety of water parameters will be tested and recorded in advance. These parameters
include: water temperature, dissolved oxygen, alkalinity, carbon dioxide, pH, salinity,
hardness (total and calcium), nitrate, nitrite, iron, phosphate, ammonia, and chloride.
A number of confirmed and potential breeding sites are identified and documented in
the Fish and Wildlife Management Information System (FWMIS). Selected sites should
be surveyed in detail each spring to establish or confirm the exact location of egg mass
deposition areas within breeding waterbodies, as well as the number of egg masses
present, prior to egg collection. A second survey can be conducted in late July/early
August to identify future or additional breeding sites through the presence of large
numbers of YOY localized around waterbodies used for breeding.
Survey advice and recommendations featured in the northern leopard frog survey
protocol (Kendell 2002b) and the Alberta Volunteer Amphibian Program Monitoring
Program (AVAMP) manual (Alberta Conservation Association and Alberta Sustainable
Resource Development 2006) should be followed for conducting both frog and egg
mass surveys. The location of egg masses that are considered for collection in the field
should be carefully and discreetly marked using a small piece of flagging tape tied to
natural emergent aquatic vegetation or attached to a stick that is securely pushed into
the substrate, near the egg mass. Careful notes should be taken to describe the general
position of the egg mass, and its actual position in relation to the flagging tape marker.
The ANLFRT will investigate the feasibility of establishing a captive breeding colony of
northern leopard frogs that would allow researchers to obtain eggs masses for
reintroduction without drawing on wild populations. Such a colony would better
guarantee the availability of eggs on a regular and predictable basis and eliminate a
number of logistical challenges and concerns associated with collecting eggs from the
wild.
13
2.5 Characteristics of relocation sites
Potential release sites will be evaluated against a suite of criteria to determine their
suitability for receiving founding stock (see Appendix 1). Most importantly, release
sites will be selected based on their apparent suitability for frogs and their security
from current and future habitat threats. To maximize the suitability, release sites
should:
• Occur within the limits of the recorded distribution of the species;
• Be void of remnant northern leopard frog populations. However, future
reintroductions may occur at sites currently occupied to augment existing
populations;
• Occur within a relatively short distance (i.e.,
Fish Program (riparian areas and grazing management materials) and Saunders
et al. (2006), are being followed as BMP;
• Have long‐term protective status as well as open permission for access.
Examples would include government lands such as municipal or provincial
parks, Buck for Wildlife land/ACA Conservation Sites, heritage rangelands,
national parks, national defence lands, non‐government lands such as Nature
Conservancy of Canada or Ducks Unlimited properties, or private lands
controlled by private owners with strong conservation interest and ethics.
Potential release sites should also be evaluated based on the level of local community,
and particularly, adjacent landowner support. Ideally, adjacent landowners to the
translocation sites should be informed and interested in the project, and show a
willingness to participate in stewardship and monitoring of lands adjacent to the
reintroduction site, if opportunities arise. Finally, release sites should support year‐
round vehicle and foot access within a reasonable distance of breeding and over‐
wintering waterbodies, as well as neighbouring upland habitats. This will help support
monitoring and research activities.
3.0 REINTRODUCTION PROCESS
The act of physically moving eggs (or occasionally, hatchling tadpoles) from one site to
another involves many individual actions that must be conducted in a manner that
maximizes the probability of eggs hatching, or the survival of hatchling tadpoles. The
following protocol is suggested as a process for collecting and moving eggs and
hatchling tadpoles from source sites to recipient sites.
3.1 Collection of egg masses, eggs, and hatchling tadpoles
• Eggs should be collected from source sites as soon as possible following
deposition and ideally between the development stages of 1 to 15. Efforts
should be made to collect eggs before they begin to hatch; hatchling tadpoles
(i.e., development stage 17 to 20) should only be collected as a last resort.
15
• Prior to handling the eggs, hands should be free of chemicals such as insect
repellent, suntan lotion, etc., or Nitrex® rubber gloves should be worn. Hands
should be washed using soap and water, or gloves replaced, between sites.
• A maximum of 50% (one half) of observed egg masses, or eggs, should be
collected from any one breeding location. For purposes of this document, an
egg mass is defined as a globular cluster of approximately 4000 eggs, and a
breeding location is defined as a discrete area of a wetland where eggs are
deposited and that is disconnected by at least 50 m from the next breeding
location.
• Eggs that are deemed to be at risk of becoming beached, trampled by livestock,
or otherwise destroyed or damaged should be collected before eggs that are not
at risk.
• Before eggs are collected, they should be closely inspected for infectious or
contagious pathogens (i.e., fungus) and parasites. If infectious or contagious
pathogens or parasites are observed, eggs should not be collected.
• Eggs should not be handled out of water.
• When removing an entire egg mass from a waterbody it should be carefully
dislodged from the vegetation or debris to which it is attached. It may be
necessary to clip vegetation to which the egg mass is attached if the egg mass
cannot be easily dislodged.
• Individual eggs can be separated from the greater egg mass by pulling them
apart with fingers and separating them along the natural connective tissue
cleavage lines. To ensure as wide a genetic mix as possible at reintroduction
sites, it is recommended that individual eggs be collected from multiple egg
masses whenever possible. Particular care must be taken not to dislodge
remaining eggs from the vegetation or debris to which they are attached. If this
occurs, any free‐floating eggs must be enclosed in an egg mass predator
exclosure basket (Figure 4) until they hatch and reach development stage 17 to
20. Each basket should be securely anchored in place to prevent drifting into
unfavourable habitat by wind or wave action.
16
Figure 4. An egg mass predator exclosure basket. Design from Kendell 2001, 2002a,
2004a, 2004b. Photo by K. Kendell.
• A 1‐gallon polyethylene (ThermosTM) container should be used as the transport
container for each individual egg mass or eggs. Such containers should have a
wide mouth for ease of egg collection and have a screw cap to ensure the
contents of the container do not spill. The spout on the container can be left
open to allow some oxygen to reach the water.
• While underwater, the single egg mass or individual eggs (not exceeding 4000
eggs, in total) can be gently guided into the container.
• Each container should be completely filled with water from the collection site.
• Care should be taken to minimize the collection of substrate, macro‐
invertebrates, plant material, and other debris along with the egg mass, or eggs.
• Each container should be clearly marked with a letter or number that
corresponds to the collection site and applicable background information
should be noted in a field book. This background information should include
the UTM coordinates of the egg mass deposition location, date of collection, and
site name. Any other pertinent information should also be recorded.
• A photo should be taken of the collection site and logically named for future
cross‐referencing with other collection site information.
17
• Water temperature, dissolved oxygen and other basic water quality parameters
(e.g., alkalinity, carbon dioxide, pH, salinity, hardness (total and calcium),
nitrate, nitrite, iron, phosphate, ammonia, and chloride) should be collected
from the egg collection site at the time of egg collection, regardless of whether
water chemistry was noted at the site prior to the immediate collection time, or
in the previous year. Water samples should be taken within 1 m of the egg mass
deposition.
• If hatchling tadpoles between the development stages 16 ‐ 23 are collected,
identical procedures should be followed as to those outlined above for egg
masses and eggs.
3.2 Transportation of egg masses, eggs or hatchling tadpoles to recipient site
• Effort should be made to minimize any possible stress on the eggs or hatchling
tadpoles during transport, such as unnecessary jarring movements and drastic
changes in water quality in the transport container.
• Approximately one half of the total water volume in the container should be
renewed with fresh de‐chlorinated, or aged, tap water of equal temperature
every half hour of travel time until arrival at the recipient site. It is very
important that the eggs are not exposed to abrupt shocks in water quality.
Chlorine and chloramine can be removed from tap water using a tap water
conditioner such as Aqua Plus ™ or Prime ™, that are commonly sold in pet
stores (follow directions on bottle). Allowing tap water to sit for a 24‐hour
period (while exposed to air) will allow chlorine to evaporate from the water.
During transport, all waste water from the source site should be carefully
disposed of away from other waterbodies (i.e., disposed of on dry upland).
3.3 Handling of egg masses, eggs or hatchling tadpoles at recipient site
• If necessary, gradual water changes in the transport containers should continue
upon arrival at the recipient site, at a rate of half the total volume, until the total
volume of original pond water in the container is replaced by de‐chlorinated tap
water. The de‐chlorinated tap water should be of equal temperature to that of
the water within the container.
18
• Each egg mass (or eggs) should then be thoroughly and carefully rinsed with
de‐chlorinated tap water and transferred into a 25 x 30 cm, 4 ml, clear, slider
reclosable plastic bag (i.e., Ziploc ™ bag), filled with de‐chlorinated tap water of
equal temperature to that of the water within the transport container. It is
important to ensure that all waste water from the source site is disposed of
away from the recipient site waterbody, and on dry upland.
• Hatchling tadpoles should be directly transferred into a 25 x 30 cm, 4 ml, clear,
slider reclosable plastic bag (i.e., Ziploc™ bag) filled with de‐chlorinated tap
water of equal temperature to that of the water in the transport container.
• While in its respective plastic bag, each egg mass, individual eggs or hatchling
tadpoles should be closely inspected a second time for infectious or contagious
pathogens (e.g., Saprolegnia ferax). If disease or parasites are observed, infected
eggs should be removed and disposed of using tweezers or pipette, or by hand.
• Each plastic bag should then be placed into its own separate egg mass predator
exclosure basket (Figure 4).
• Egg mass predator exclosure baskets should be positioned at the release site in
similar habitat conditions from which the eggs or hatchling tadpoles were
collected (i.e., sun exposure, water depth, etc.). Each basket should be securely
anchored to prevent drifting into unfavourable habitat by wind or wave action.
• Each plastic bag should be floated for 20 minutes in its egg mass predator
exclosure basket (to equalize the water temperatures between the bag and the
recipient site waterbody), after which time water from the recipient site should
be slowly introduced into each plastic bag, equaling approximately one half of
the total water volume of the bag. It is very important that the eggs are not
exposed to abrupt shocks in water quality.
• After another 20‐minute waiting period, water from the recipient site should be
again slowly introduced into each plastic bag, equaling approximately one half
of the total water volume of the bag. Following an additional 20‐minute waiting
period, each egg mass (or eggs) can be liberated into its separate and individual
egg mass predator exclosure basket. Total acclimatization time for the egg
masses and eggs should last about one hour.
19
3.4 Egg and hatchling tadpole monitoring schedule
• Egg masses and eggs should be monitored every two days, between the
development stages 1 to 15, at which time they should be closely inspected for
infectious or contagious pathogens such as Saprolegnia ferax. Infected eggs
should be removed and disposed of using tweezers or pipette, or by hand. The
number of dead and diseased eggs that are removed from each egg mass
predator exclosure should be counted and recorded.
• After development stage 15, eggs should be monitored every two days until
they reach stages 25 to 26 of development. During this monitoring period, the
hatchling tadpoles should be closely inspected for infectious or contagious
pathogens. Any eggs that failed to hatch, as well as deceased tadpoles should
be counted and recorded, then removed and disposed of using tweezers or
pipette, or by hand.
• If tadpoles are the life stage of the frogs translocated (i.e., hatchling tadpoles are
collected), identical procedures should be followed as those outlined above.
• Care should be taken to sterilize any tools or equipment that come into contact
with diseased animals or that are shared between egg mass predator exclosure
baskets (see Section 2.1).
3.5 Release of tadpoles at recipient site
• Egg masses, eggs and hatchling tadpoles should remain in their respective egg
mass predator exclosure basket until they reach approximately stage 26 of
development. At this stage of development, the hatchling tadpoles assume the
typical tadpole body shape and become fairly mobile and active.
• Prior to release, the tadpoles should be counted and exact numbers recorded.
• Counting of tadpoles should ideally occur during the time of the day when air
temperature is at its peak (i.e., mid day) and ideally under sunny and calm
weather conditions. This will help ensure that water conditions are optimal to
support tadpole movements and thus increase the chance for tadpoles to
disperse into preferred habitats and avoid predators, once released.
20
• Precise numbers can be counted using a handheld tally counter and a three‐inch
nylon (gravy) strainer. Care must be taken not to injure tadpoles as they are
counted using the strainer. To maintain accuracy and efficiency while counting
tadpoles, a maximum of 8 tadpoles (optimally, 1 ‐ 5 tadpoles) should be dipped
with a strainer at one time.
• Counted tadpoles should be quickly moved from the strainer to a wash basin
(approximately 5‐L capacity), or similar container, that is filled with water from
the recipient site.
• Efforts should be made to minimize the time the tadpoles are out of the water as
they are counted and transferred from their egg mass predator exclosure basket
to their wash basin.
• Tadpoles should be released into the same waterbody in which their egg mass
predator exclosure was located.
• Tadpoles should be released in sheltered sections of the recipient waterbody
and in shallow water (i.e., areas that possess water depths of 10 cm or less) that
supports optimal tadpole development.
• Tadpoles should have easy access to water deeper than 10 cm.
• Tadpole releases should occur over a broad area at the recipient site (e.g., along
a 30‐m stretch of shoreline with suitable shallow water areas) to lessen the
impact of any possible predators or catastrophic events.
Tadpoles should NOT be released in areas:
• At risk of sudden lowering of water levels that may leave tadpoles beached or
trapped in small isolated pools;
• Where the chance of depredation is increased (e.g., in areas with a high number
of wading birds);
• With water currents or strong wave action that may force tadpoles into
unfavourable habitats, or cause beaching;
• Void of submerged and emergent aquatic vegetative cover;
• That otherwise put the tadpoles at risk (e.g., trampling by cattle, etc.).
21
4.0 MONITORING ACTIVITIES AND SCHEDULE
Monitoring of populations and habitats is required at specific intervals or on an
ongoing basis to:
• Confirm vacancy of potential reintroduction sites (pre‐release);
• Determine size of source population before eggs are removed (see Section 2.4);
• Monitor source and release sites for presence of disease;
• Determine water chemistry and quality, and match (as closely as possible)
characteristics of source and release sites (pre‐release);
• Monitor success of reintroductions and potential effects on source sites; the
latter via regular planned provincial northern leopard frog inventories (i.e.,
every five years) (ANLFRT 2005).
4.1 Year one (first year of egg translocation)
• YOY surveys should be undertaken between mid‐July and early August to
provide information on survivorship through metamorphosis and the
productivity of the recipient site.
• At least one fall survey should be undertaken to determine the habitats in which
the reintroduced frogs are attempting to over‐winter.
4.2 Year two (second year of egg translocation)
• At least one spring or summer survey of release site(s) to confirm successful
over‐wintering of released frogs.
• At least one fall survey to determine the habitats in which the frogs are
attempting to over‐winter.
4.3 Year three
At least one spring and summer survey of release site(s) should be undertaken to
confirm over‐wintering of released frogs from years one and two, to look for evidence
of breeding (calling and/or egg deposition) by frogs released in year one, and confirm
survivorship of eggs through metamorphosis.
22
4.4 Five‐year inventory cycle
Reintroduction sites with successful frog establishment should be surveyed as part of
regular planned provincial northern leopard frog inventories (i.e., every five years) to
confirm continued successful over‐wintering and/or breeding of frogs at the site, as
well as relative abundance (ANLFRT 2005).
5.0 ASSESSMENT OF SUCCESS
In the context of reintroduction, the ANLFRT has defined success as evidence of an
established, self‐sustaining population of northern leopard frogs at a given release site.
This success will be further defined under three categories (initial success, intermediate
success and complete success), which will be measured against a number of events and
occurrences under each category:
5.1 Initial success
• Introduced egg masses and eggs successfully hatch (i.e., more than 90% of all eggs
collected hatch).
5.2 Intermediate success (year one and two)
• In two consecutive years, juvenile frogs successfully over‐winter at the selected
release site.
5.3 Complete success (year three)
• Frogs survive to the age of sexual maturity (~ 2 years of age) and upon reaching
sexual maturity, breeding activity is observed at the release site (e.g., calling males
and amplexus) and egg masses or tadpoles are documented.
• Naturally procured egg masses and tadpoles survive metamorphosis and emerge as
juvenile frogs from their natal pond (i.e., YOY observed).
23
24
• Breeding continues to occur at the release site, and a self‐sustaining (stable)
population is established with a minimum of eight adult frogs per person‐hour of
survey effort (post breeding season – i.e., June ‐ August).
6.0 LITERATURE CITED Alberta Conservation Association and Alberta Sustainable Resource Development.
2006. Alberta Volunteer Amphibian Monitoring Program ‐ participants manual.
Alberta Conservation Association, Edmonton, Alberta. 46 pp.
Adama, D.B., K. Lansley, and M.A. Beaucher. 2003. Captive rearing and reintroduction
of northern leopard frogs (Rana pipiens) in the Creston Valley Wildlife
Management Area, 2002. Report to the Columbia Basin Fish and Wildlife
Compensation Program, Nelson, British Columbia. 35 pp.
Adama, D.B., K. Lansley, and M.A. Beaucher. 2004. Northern leopard frog (Rana
pipiens) recovery: captive rearing and reintroduction in southeast British
Columbia, 2003. Report to the Columbia Basin Fish and Wildlife Compensation
Program, Nelson, British Columbia. 26 pp.
Alberta Environmental Protection. 1996. The Wildlife Act. Alberta Environmental
Protection, Natural Resource Service, Edmonton, Alberta. 212 pp.
Alberta Northern Leopard Frog Recovery Team. 2005. Alberta northern leopard frog
recovery plan, 2005‐2010. Alberta Sustainable Resource Development, Fish and
Wildlife Division, Alberta Species at Risk Recovery Plan No. 7, Edmonton,
Alberta. 26 pp.
Alberta Sustainable Resource Development. 2003. Status of the northern leopard frog
in Alberta: update 2003. Alberta Sustainable Resource Development, Fish and
Wildlife Division, and Alberta Conservation Association, Wildlife Status Report
No. 9 (Update 2003), Edmonton, Alberta. 61 pp.
Berger L, R. Speare, P. Daszak, D.E. Green, A.A. Cunningham, C.L. Goggin, R.
Slocombe, M.A. Ragan, A.D. Hyatt, K.R. McDonald, H.B. Hines, K.R. Lips, G.
Marantelli, and H. Parkes. 1998. Chytridiomycosis causes amphibian mortality
associated with population declines in the rain forests of Australia and Central
America. Proceedings in the National Academy of Science USA 95: 9031–9036.
25
Blaustein, A.R., and J.M. Kiesecker. 2002. Complexity in conservation: lessons from the
global decline of amphibian populations. Ecology Letters 5: 597–608.
Blaustein, A.R., D.G. Hokit, R.K. O’Hara, and R.A. Holt. 1994. Pathogenic fungus
contributes to amphibian losses in the Pacific Northwest. Biological
Conservation 67: 251–254.
Bosch J., and I.M. Solano. 2006. Chytrid fungus infection related to unusual mortalities
of Salamandra salamandra and Bufo bufo in the Peñalara Natural Park, Spain.
Oryx 40: 84–89.
Canadian Cooperative Wildlife Health Centre. Wildlife Disease Investigation Manual.
The Prairie Diagnostic Services, 52 Campus Dr., Saskatoon, Saskatchewan.
Commonwealth of Australia. 2006. Background document for: the threat abatement
plan: infection of amphibians with chytrid fungus resulting in
Chytridiomycosis. Department of the Environment and Heritage, Australia. 64
pp.
Corn, P.S., and L.J. Livo. 1989. Leopard frog and wood frog reproduction in Colorado
and Wyoming Northwest. Naturalist 17: 1‐9.
Cunjak, R.A. 1985. Winter habitat of northern leopard frogs (Rana pipiens) in a
southern Ontario stream. Canadian Journal of Zoology 64: 255‐257.
Dole, J.W. 1968. Homing in leopard frogs, Rana pipiens. Ecology 49: 386‐399.
Emery, A.R., A.H. Berst, and K. Kodaira. 1972. Under‐ice observations of wintering
sites of leopard frogs. Copeia 1972: 123‐126.
Fisher, C. 1999. Feasibility of northern leopard frog translocation in Alberta: a review
of physiological, ecological, and methodological requirements for successful
repatriations and results from field investigation. Alberta Environment,
Fisheries and Wildlife Management Division, Edmonton, Alberta. 35 pp.
26
Gosner, K.L. 1960. A simplified table for staging anuran embryos and larvae with
notes on identification. Herpetologica 16: 183‐190.
Government of Alberta. 2006. URL: www.gov.ab.ca/home.
Greer A. L., M. Berrill, P.J. Wilson. 2005. Five amphibian mortality events associated
with ranavirus infection in south central Ontario, Canada. Diseases of Aquatic
Organisms 67: 9‐14.
Hine, R.L., B.L. Les, and B.F. Hellmich. 1981. Leopard frog populations and mortality
in Wisconsin, 1974‐76. Wisconsin Department of Natural Resources Technical
Bulletin 122: 1‐39.
Hecnar, S.J., and R.T. M’Closkey. 1997. The effects of predatory fish on amphibian
species richness and distribution. Biological Conservation 79: 123‐131.
Hird, D.W., S.L. Diesch, R.G. McKinnell, E. Gorham, F.B. Martin, C.A. Meadows, and
M. Gasiorowski. 1983. Enterobacteriaceae and Aeromonas hydrophila in
Minnesota frogs and tadpoles (Rana pipiens). Applied and Environmental
Microbiology 46: 1423‐1425.
Holt, A.R. 1994. Pathogenic fungus contributes to amphibian losses in the Pacific
Northwest. Biological Conservation 67: 251‐254.
Kendell, K. 2000. Investigation of northern leopard frog (Rana pipiens) overwintering
ecological requirements in NAWMP managed wetland complexes and other
wetland sites in southern Alberta. Alberta Environment, Fisheries and Wildlife
Management Division, Edmonton, Alberta. 32 pp.
Kendell, K. 2001. Northern leopard frog reintroduction: Raven River year 2 (2000).
Alberta Sustainable Resource Development, Fish and Wildlife Service, Alberta
Species at Risk Report No. 13, Edmonton, Alberta. 43 pp.
27
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Search&itool=pubmed_AbstractPlus&term=%22Greer+AL%22%5BAuthor%5Dhttp://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Search&itool=pubmed_AbstractPlus&term=%22Wilson+PJ%22%5BAuthor%5Dhttp://biology.usgs.gov/s+t/noframe/d053.htm#12371#12371
Kendell, K. 2002a. Northern leopard frog reintroduction: year 3 (2001). Alberta
Sustainable Resource Development, Fish and Wildlife Division, Alberta Species
at Risk Report No. 42, Edmonton, Alberta. 45 pp.
Kendell, K. 2002b. Survey protocol for the northern leopard frog. Alberta Sustainable
Resource Development, Fish and Wildlife Division, Alberta Species at Risk
Report No. 43, Edmonton, Alberta. 30 pp.
Kendell, K. 2002c. Alberta inventory for the northern leopard frog (2000‐2001).
Alberta Sustainable Resource Development, Fish and Wildlife Division, Alberta
Species at Risk Report No. 44, Edmonton, Alberta. 29 pp.
Kendell, K. 2004a. Northern leopard frog reintroduction: year 5 (2003). Alberta
Conservation Association, Edmonton, Alberta. 14 pp.
Kendell, K. 2004b. Northern leopard frog reintroduction: year 6 (2004). Progress
report for Alberta Sustainable Resource Development and the Alberta
Conservation Association, Edmonton, Alberta. 8 pp.
Kendell, K., Stevens, S., and D. Prescott. 2007. Alberta northern leopard frog survey,
2005. Technical Report, T‐2007‐001, produced by the Alberta Conservation
Association, Edmonton, Alberta, Canada. 17 pp + App.
McCallum, H. 2005. Inconclusiveness of chytridiomycosis as the agent in widespread
frog declines. Conservation Biology 19: 1421–1430.
Merrell, D.J., and C.F. Rodell. 1968. A comparison of the estimated size and the
“effective size” of breeding populations of the leopard frog, Rana pipiens.
Evolution 22: 274‐283.
Nace, G.W., D.D. Culley, M.B. Emmons, E.L. Gibbs, V.H. Hutchison, and R.G.
McKinnell. 1996. Amphibians: guidelines for the breeding, care, and
management of laboratory animals. A report of the Subcommittee on
Amphibian Standards, Committee on Standards, Institute of Laboratory Animal
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Resources, and National Research Council. National Academy of Sciences,
Washington, D. C. 154 pp.
Pessier A.P., D.K. Nichols, J.E. Longcore, and M.S. Fuller 1999. Cutaneous
chytridiomycosis in poison dart frogs (Dendrobates spp.) and White’s tree frogs
(Litoria caerulea). Journal of Veterinary Diagnostic Investigation 11: 194–199.
Roberts, W.E. 1981. What happened to the leopard frog? Alberta Naturalist 11: 1‐4.
Roberts, W.E. 1987. The northern leopard frog endangered in Alberta. Pp. 137‐138. In:
G.L. Holroyd, W.B. McGillivray, P.H. Stepney, D.M. Ealey, G.C. Trottier, and
K.E. Eberhart. Endangered species in the prairie provinces. Provincial Museum
of Alberta Natural History Occasional Paper No. 9. Provincial Museum of
Alberta, Edmonton, Alberta. 367 pp.
Roberts, W.E. 1991. An action plan for the recovery of the northern leopard frog in
Alberta. Pp. 199‐200. In: G.L Holroyd, G. Burns, H.C. Smith. Proceedings of the
Second Endangered Species and Prairie Conservation Workshop. Provincial
Museum of Alberta Natural History Occasional Papers, No. 15. Provincial
Museum of Alberta, Edmonton, Alberta. 284 pp.
Roberts, W.E. 1992. Declines in amphibian populations in Alberta. Pp. 14‐16. In: C.A.
Bishop, and K.E. Petit. Declines in Canadian amphibian populations: designing
a national monitoring strategy. Canadian Wildlife Service Occasional Papers
No. 76. Canadian Wildlife Service, Ottawa, Ontario. 120 pp.
Romanchuk, K.A., and R.W. Quinlan. 2006. Magrath northern leopard frog
reintroduction project: final report. Alberta Sustainable Resource Development,
Fish and Wildlife Division, Alberta Species at Risk Report No. 104. Edmonton,
Alberta. 33 pp.
Saunders, E., R. Quinlan, P. Jones, B. Adams, and K. Pearson. 2006. At home on the
range: living with prairie species at risk. Alberta Conservation Association and
Albert Sustainable Resource Development, Lethbridge, Alberta. 47 pp.
29
Semlitsch, R.D. 1998. Biological delineation of terrestrial buffer zones for pond‐
breeding salamanders. Conservation Biology 12: 1113‐1119.
Semlitsch, R.D., and J.R. Bodie. 2003. Biological criteria for buffer zones around
wetlands and riparian habitats for amphibians and reptiles. Conservation
Biology 17: 1219–1228.
Smith, B. 2003. Conservation assessment of the northern leopard frog in the Black Hills
National Forest, South Dakota and Wyoming. Department of Biology, Black
Hills State University, Spearfish, South Dakota. 78 pp.
Smith, B., and D.A. Keinath. 2007. Northern leopard frog (Rana pipiens): a technical
conservation assessment. Prepared for the USDA Forest Service, Rocky
Mountain Region, Species Conservation Project. 66 pp.
Smith, A., M., and D.M. Green. 2005. Dispersal and the metapopulation paradigm in
amphibian ecology and conservation: are all amphibian populations
metapopulations? Ecography 28: 110‐128
Tischendorf, L. 2007. Northern leopard frog (Rana pipiens) population viability and
reintroduction analysis. Technical Report prepared by ELUTIS Modelling and
Consulting Inc. for Parks Canada, Ottawa, Ontario. 23 pp.
Ultsch, G.R., T.E. Graham, and C.E. Crocker. 2000. An aggregation of overwintering
leopard frogs, Rana pipiens, and common map turtles, Graptemys geographica, in
northern Vermont. Canadian Field‐Naturalist 114: 314‐315.
U.S. Department of Interior. 2002. A proposal to reintroduce the northern leopard frog
(Rana pipiens) on the Flathead Indian Reservation – environmental assessment.
Department of the Interior, Bureau of Indian Affairs for the Confederated Salish
and Kootenai Tribes, Wildlife Program, Natural Resources Department, Pablo,
Montana. 17 pp.
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Waye, H.L., and J.M. Cooper. 2001. Status of the northern leopard frog (Rana pipiens) in
the Creston Valley Wildlife Management Area 1999 for the Columbia Basin Fish
and Wildlife Compensation Program. 51 pp.
Wendlandt, M., and L. Takats. 1999. Northern leopard frog reintroduction: Raven
River – pilot year (1999). Alberta Environment, Fisheries and Wildlife
Management Division, Edmonton, Alberta. 22 pp.
Whiteside, D.P., D. Prescott, and K. Kendell. 2007. Diagnostic testing for emerging
amphibian diseases in Alberta. Calgary Zoo Animal Health Centre, Calgary,
Alberta. 6 pp.
Wind, E. 2002. Northern leopard frog (Rana pipiens) husbandry manual. A report
produced for the Columbia Basin Fish and Wildlife Compensation Program,
Nelson, BC, and the Ministry of Water, Land and Air Protection, Victoria,
British Columbia. 69 pp.
7.0 APPENDIX
Appendix 1. Northern leopard frog release site suitability checklist.
Breeding habitat
Breeding habitats are man‐made or natural bodies of standing water that are shallow,
(ideally) fishless, and possess abundant submerged and emergent aquatic vegetation.
Examples include: ponds, marshes, oxbows of rivers, beaver ponds, backwaters of
flowing waterbodies, irrigation ditches, dugouts, lake margins, reservoirs, etc. Sizes of
these breeding habitats can vary.
• Breeding habitat should consist of at least two (preferably three) suitable
breeding waterbodies within 500 m of each other that are permanent or have
some degree of permanence (i.e., maintain sufficient water until end of August
in all years). Ideally, suitable breeding waterbodies at a given site should less
than 200 m apart.
• Should possess abundant submerged and emergent aquatic vegetation with
open water areas.
• Should possess shallow ( 5 ha in size
(Hine et al. 1981; Smith 2003).
32
• Should not be influenced by water use practices such as irrigation or watering of
livestock, unless BMP are followed and such practices demonstrate no harm to
northern leopard frogs.
Upland habitat
Upland habitats surround breeding and winter habitats and are typically areas that
provide foraging opportunities (available prey) and sufficient cover (protection from
climatic conditions and predators).
• Should possess open or semi‐open areas with vegetation varying in structure,
density and height.
• BMP should be used in habitats including and surrounding breeding and over‐
wintering waterbodies.
• At least 200 m of suitable habitat should surround breeding and over‐wintering
habitats and occur on either side of dispersal corridors between breeding and
over‐wintering habitats (Semlitsch 1998; Semlitsch and Bodie 2003.).
Winter habitat
Winter habitats are waterbodies that are typically deep, flowing, or warmed by ground
water or springs and thus, do not freeze to the bottom and maintain sufficient dissolved
oxygen to meet the respiration requirements of submerged over‐wintering frogs. They
may be natural or man‐made. Depth can vary, as long as dissolved oxygen (D.O.) is
high and there is enough water to cover the frogs. Water temperature during winter
must be at least 4oC, or colder.
• D.O. should ideally be at least 7 ppm (Emery et al. 1972; Cunjak 1985; Nace et al.
1996; Kendell 2000; Ultsch et al. 2000).
• Winter water temperatures should be at 4oC, or less (Nace et al. 1996; Ultsch et
al. 2000).
• Bottom substrate of over‐wintering waterbodies must remain ice‐free.
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34
Landscape connectivity
• No barriers (e.g., dense vegetation, steep cliffs, barren ground, or roads) should
fragment seasonal habitats (i.e., breeding, summer and over‐wintering).
• Ideally, population movement and dispersal capabilities should be possible at
least 10 km in any direction from breeding ponds into unoccupied suitable
habitat (i.e., availability of at least one additional suitable breeding and over‐
wintering site within 10 km of release site).
• Ideally, breeding and wintering habitats should be no more than 50 m apart.
Adjacent landuse
Approved and current Alberta Sustainable Resource Development recommended
wildlife landuse guidelines should be followed for industrial developments around
northern leopard frog habitat (i.e., 200 m set back distance – see
http://www.srd.gov.ab.ca/fw/landuse/index.html)
• Crop and other agricultural monocultures occur at least 500 m from breeding,
over‐wintering, or dispersal corridors.
• Spring snowmelt and rain run‐off patterns originate from areas void of
pollution (agriculture, industry, urban, etc.).
• Where applicable, BMP are followed at all release sites.
CONSERVATIONCONSERVATIONREPORT REPORT SERIESSERIES
The Alberta Conservation Association acknowledges the following partner for their generous support of
this project
pakuAlberta logo
NLFR_RS_coverElinor Lk 03 FWIN Final version - PA 3 Aug 06.pdf EXECUTIVE SUMMARY ACKNOWLEDGEMENTSLIST OF FIGURES LIST OF TABLES1.0 INTRODUCTION1.1 General introduction1.2 Study rationale
2.0 STUDY AREA3.0 MATERIALS AND METHODS3.1 Survey method3.2 Biological data3.3 Data analysis
4.0 RESULTS 4.1 Walleye abundance and population structure metrics4.2 Age-class distribution and stability
5.0 REFERENCES CITED 6.0 APPENDICES6.1 Appendix 1. Catch from the Fall walleye index netting at Elinor Lake, 2003. 6.2 Appendix 2. Biological data collected from the Fall Walleye Index Netting activity at Elinor Lake, 2003. Species code: WALL = walleye, NRPK = northern pike, Sex code: M = male, F = female.
NLFR_KendellandPrescott_kkeditedBack cover AB logo only