JUNE 2009 • VOLUME 6 NUMBER 2

ISSN 1612-9202 (Print)

ISSN 1612-9210 (Electronic)

10393 • 6(2) 000-000 (2009)

Conservation Medicine • Human Health • Ecosystem Sustainability

ECOHEALTH2017 • VOLUME 14 NUMBER S1

ISSN 1612-9202 (Print)ISSN 1612-9210 (Electronic)10393 • 14(S1 ) 000-000 (2017)

One Health • Ecology & Health • Public Health

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ECOHEALTH Health and Disease in Translocated Wild Animals

ECOHEALTH

ART ICLES

In This Issue 1Alien Parasites May Survive Even if Their Original Hosts Do Not 3Wojciech Solarz, Kamil Najberek

Health and Disease in Translocated Wild Animals 5Ian Carter, Anthony W. Sainsbury, Katherine Walsh, Hartley Matthew, Jon Curson, John G. Ewen

The Role of Animal Translocations in Conserving British Wildlife: An Overview of Recent Work and Prospects for the Future 7Ian Carter, Jim Foster, Leigh Lock

Methods of Disease Risk Analysis in Wildlife Translocations for Conservation Purposes 16Matt Hartley, Anthony Sainsbury

A Comparison of Disease Risk Analysis Tools for Conservation Translocations 30Antonia Eleanor Dalziel, Anthony W. Sainsbury, Kate McInnes, Richard Jakob-Hoff, John G. Ewen

Which Parasites Should We be Most Concerned About in Wildlife Translocations? 42Bruce A. Rideout, Anthony W. Sainsbury, Peter J. Hudson

Using Qualitative Disease Risk Analysis for Herpetofauna Conservation Translocations Transgressing Ecological and Geographical Barriers 47Mariana Bobadilla Suarez, John G. Ewen, Jim J. Groombridge, K. Beckmann, J. Shotton, N. Masters, T. Hopkins, Anthony W. Sainsbury

Parasites as Drivers and Passengers of Human-Mediated Biological Invasions 61Tim M. Blackburn, John G. Ewen

Bringing Back a Healthy Buzz? Invertebrate Parasites and Reintroductions: A Case Study in Bumblebees 74Mark J. F. Brown, Anthony W. Sainsbury, Rebecca J. Vaughan-Higgins, Gavin H. Measures, Catherine M. Jones, Nikki Gammans

Biosecurity for Translocations: Cirl Bunting (Emberiza cirlus), Fisher’s Estuarine Moth (Gortyna borelii lunata), Short-Haired Bumblebee (Bombus subterraneus) and Pool Frog (Pelophylax lessonae) Translocations as Case Studies 84R. J. Vaughan-Higgins, N. Masters, A. W. Sainsbury

Effects of Lead Exposure, Flock Behavior, and Management Actions on the Survival of California Condors (Gymnogyps californianus) 92Victoria J. Bakker, Donald R. Smith, Holly Copeland, Joseph Brandt, Rachel Wolstenholme, Joe Burnett, Steve Kirkland, Myra E. Finkelstein

Protecting Free-Living Dormice: Molecular Identification of Cestode Parasites in Captive Dormice (Muscardinus avellanarius) Destined for Reintroduction 106Gabriela Peniche, Peter D. Olson, Dominic J. Bennett, Louise Wong, Anthony W. Sainsbury, Christopher Durrant

Evaluating the Effects of Ivermectin Treatment on Communities of Gastrointestinal Parasites in Translocated Woylies (Bettongia penicillata) 117Amy S. Northover, Stephanie S. Godfrey, Alan J. Lymbery, Keith Morris, Adrian F. Wayne, R. C. Andrew Thompson

Evaluating Stress Physiology and Parasite Infection Parameters in the Translocation of Critically Endangered Woylies (Bettongia penicillata) 128Stephanie Hing, Amy S. Northover, Edward J. Narayan, Adrian F. Wayne, Krista L. Jones, Sarah Keatley, R. C. Andrew Thompson, Stephanie S. Godfrey

Outcomes of a ‘One Health’ Monitoring Approach to a Five-Year Beaver (Castor fiber) Reintroduction Trial in Scotland 139Gidona Goodman, Anna Meredith, Simon Girling, Frank Rosell, Roisin Campbell-Palmer

A Model to Inform Management Actions as a Response to Chytridiomycosis-Associated Decline 144Sarah J. Converse, Larissa L. Bailey, Brittany A. Mosher, W. Chris Funk, Brian D. Gerber, Erin Muths

Volume 14, Supplement 1

2017

On the Cover: “The Lion, the Fox, andthe Ass" (2010) by Ellen Tanner. Oil paint on canvas, 12” x 14”. Privatecollection in USA. This artwork wassponsored by the generous support ofEcoHealth Alliance.

ECOHEALTH

Monitoring for the Management of Disease Risk in Animal Translocation Programmes 156James D. Nichols, Tuula E. Hollmen, James B. Grand

Tiptoeing Cautiously Yet Confidently: Health Considerations for Conservation Translocations 167Axel Moehrenschlager

Abstracted or indexed in: Academic OneFile, Biological Abstracts, BIOSIS Previews, Business Source,CSA/Proquest, Current Abstracts, Current Awareness in Biological Sciences (CABS), CurrentContents/Agriculture, Biology & Environmental Sciences, Elsevier Biobase, EMBASE, EMBiology,Environment Index, Gale, GeoRef, Google Scholar, Journal Citation Reports/Science Edition, OCLC,PubMed/Medline, Science Citation Index Expanded (SciSearch), SCOPUS, Summon by Serial Solutions,TOC Premier, Zoological Record

Health and Disease in Translocated Wild Animals

Why have species conservation translocations become so

important as a conservation tool? In short, because historic

and ongoing losses and degradation have severely reduced

our wildlife habitats. Increasingly, species struggle to persist

in the wild and fragmentation of remaining habitat makes

moving across hostile landscapes between suitable sites

difficult. Direct human intervention is essential to help

many threatened species survive and, in some cases, to

restore those that have already been lost.

In Britain, for example, we have the opportunity to see

species like the white-tailed eagle (Haliaeetus albicilla),

beaver (Castor fiber), pool frog (Pelophylax lessonae) and

large blue butterfly (Maculinea arion) only because they

have been reintroduced (one form of conservation

translocation). The conservation status of many other

species has been improved because of translocations from

one site to another. This Special Issue describes some of the

painstaking work that has gone into ensuring that these

conservation translocations are done responsibly with re-

spect to the health and disease risks inherent in such

interventions. These conservation translocation efforts can

be celebrated for placing these species on a much firmer

footing. Considerations of health and disease in responsible

conservation translocations are also playing vital roles in

saving species globally, for example the California Condor

(Gymnogyps californianus) (Bakker et al, this Issue).

In a world where we hear so much gloomy news about

the environment, conservation translocations provide some

hope, a tangible sign that we can make a difference if we

choose to. And critically, by focussing conservation effort

on single, often high-profile species, restoration work helps

to substantially improve habitats for a wide range of other

wildlife. This approach is about far more than simply

‘cherry-picking’ a few token species to save. Increasingly,

species are selected exactly because of the important

ecosystem functions they perform and ecosystem restora-

tion has frequently become the fundamental objective of

these programmes.

Conservation translocations can help restore species

and/or ecosystem functions, but done badly they can do

more harm than good. Much has changed in our under-

standing of good translocation practice in the last few

decades and the importance of taking disease risks into

account when moving species from place to place is now far

more widely recognised. In the past, the health of translo-

cated animals may have been left to chance when species

were moved around. Sometimes, we got away with it… and

sometimes we were not so lucky. We now have much better

systems in place to assess and minimise the risks from

diseases and parasites. These are reflected in protocols and

guidelines on this subject (OIE and IUCN 2014) and are a

core focus of this Special Issue. For example, Dalziel et al

(in this Issue) contrast three methods for qualitative disease

risk analysis available to practitioners for conservation

translocations, while Hartley and Sainsbury review the pros

and cons of all available methods, and Brown et al provide

an important case study on short-haired bumblebee

(Bombus subterraneus) translocation. Two further contri-

butions outline methods which potentially make important

advances in the analysis of the risk from disease in

undertaking translocation: Bobadilla Suarez et al explain

how an understanding of the geographical and ecological

barriers crossed in a translocation is essential to distinguish

high-risk from lower risk translocations and Rideout et al

set out the traits of non-native parasites which would in-

crease their ability to invade, persist and spread and

therefore increase risk from disease. Further developments

in disease risk analysis methods for conservation translo-

cations can be expected as the number of translocations

analysed increases, our evidence-base on effectiveness is

EcoHealth 14, S5–S6, 2017DOI: 10.1007/s10393-016-1200-2

Editorial

� 2016 International Association for Ecology and Health

enhanced and post-release monitoring methods improve,

providing crucial feedback on disease impact at the desti-

nation. Setting and maintaining high standards not only

increases the chances that individual projects will succeed

but also helps minimise the risk that there will be adverse

effects on other wildlife.

Practices to manage risk from disease following

translocation benefit from models to predict the spatial and

temporal patterns of risks (Bakker et al), molecular meth-

ods to identify suspected hazards (Peniche et al), analyses

of biosecurity methods (Vaughan-Higgins et al) and studies

on the ecosystem effects of therapeutic treatment of

translocated animals (Northover et al). Decision-analytic

models for predicting the effects of multiple risk manage-

ment options on the outcome of translocation (Converse

et al) offer potential advantages in assessing the relative

importance of management decisions in the face of

uncertainty. Post-release disease monitoring is crucial to

learn lessons from a conservation translocation and ensure

that future management decisions reduce the risk from

disease (Nichols et al).

Species are moved from one place to another with

alarming frequency for reasons outside the remit of con-

servation translocation (as defined by the IUCN 2013)

including for development, trade, hunting and amenity

purposes, often without sufficient controls. We strongly

encourage that all animal movements should be subject to

the same high standards of disease risk analysis as those

discussed in this special issue for conservation transloca-

tions. Only in this way can we reduce the accidental neg-

ative outcomes that occur because of translocations, and

also continue to test and improve on the methods we use.

Ian Carter, Katherine Walsh, and Jon Curson

Natural England, York, UK

Anthony W. Sainsbury, and John G. Ewen

Institute of Zoology,

Zoological Society of London, London, UK

e-mail: tony.sainsbury@ioz.ac.uk

Hartley Matthew

University of Chester, Chester, UK

ACKNOWLEDGMENTS

This Special Issue sprang from a joint Zoological Society of

London, Natural England and Royal Society for the

Protection of Birds Symposium, held at the Zoological

Society of London, which celebrated 25 years of the

Zoological Society of London and Natural England part-

nership in Health Surveillance for the Species Recovery

Programme. We would like to thank all the speakers and

chairs who contributed to the symposium: Katie Beck-

mann, Tim Blackburn, Mark Brown, Stefano Canessa,

Sarah Converse, Ruth Cromie, Molly J Dickens, Myra

Finkelstein, Jim Foster, Andrew Greenwood, Tim Hill,

Peter J Hudson, Carl Jones, Richard Kock, Leigh Lock, Nic

Masters, Tony Mitchell-Jones, Axel Moehrenschlager,

James D Nichols, Gabriela Peniche, Bruce Rideout, Richard

Shore and Rebecca Vaughan-Higgins. Special thanks to the

Symposium Coordinator, Jennifer Howes, and the Head of

Scientific Publications, Linda DaVolls, for organising a

brilliant event.

REFERENCES

International Union for the Conservation of Nature (2013) IUCNGuidelines on Reintroduction and other Conservation Transloca-tions, Gland: IUCN

World Organisation for Animal Health (OIE) & InternationalUnion for Conservation of Nature (IUCN) (2014) Guidelinesfor Wildlife Disease Risk Analysis. OIE, Paris. Published inassociation with the IUCN and the Species Survival Commis-sion, pp 24

Published online: December 19, 2016

S6 A. W. Sainsbury et al.

In This Issue

HEALTH AND DISEASE IN TRANSLOCATED

WILD ANIMALS

Carter et al. begin this Supplemental Issue of EcoHealth on

Health and Disease in Translocated Wild Animals with an

overview of terrestrial animal translocations carried out for

conservation purposes in Britain, summarizing what has

been achieved in recent decades and discussing the issues

raised by this approach to conservation. Moving species

around is a complex undertaking, and understanding of the

inherent risks involved, including the risks from disease, has

improved significantly in recent years. The authors recom-

mend that conservation translocations should be considered

in the context of species recovery targets and that high

standards should be maintained so that disease risks and

other potentially negative impacts are minimized. Hartley

and Sainsbury follow up by describing the use of disease risk

analysis, and propose modification of methods for wildlife

translocations undertaken for conservation purposes. The

challenges of these specific scenarios, including hazard

identification, multiple epidemiological pathways, and data

gaps, are addressed. Tools, which could improve the use-

fulness of the technique, are also described. Examples are

taken from the 25 years’ work of the UK Species Recovery

Program. Wildlife translocations happen all over the world

with varied success, while disease is a known potential

complicating factor of translocations.Dalziel et al. provide a

comparison of three different qualitative methods of disease

risk analysis (DRA) using the translocation of Hihi, a New

Zealand passerine bird, as a case study. DRAs are advised for

all species translocations, but themethod used to conduct the

DRA can have an effect on the result the user receives. They

recommend that users of DRAs understand the limitations

and strengths of the method they use, and become familiar

with their idiosyncrasies.

Parasites, in the broad sense, including viruses, bacte-

ria, fungi, protozoa, and metazoa, play an important role in

normal ecosystem function. As a result, parasites native to a

host in its natural habitat should raise little concern for

wildlife translocations, although there are exceptions.

Rideout et al. explain the parasites of greatest concern are

those that are alien to a particular host in its natural habitat

and have characteristics that facilitate invasion and persis-

tence in a novel host population. Bobadilla Suarez et al.

follow with an explanation of how qualitative disease risk

analysis has been used in four herpetofauna conservation

translocations to assess the risk from disease to translocated

and recipient populations. They describe how ecological

and geographical barriers influence the number and cate-

gory of parasite hazards and the level of risk from disease in

each translocation. They also demonstrate how simplifica-

tion of the translocation pathway through avoidance of

barriers can reduce risk from disease. Blackburn and Ewen

argue biological invasions by alien species are one of the

main ways in which human activities are changing the

environment. Parasites have frequently been invoked as

influencing the invasion success of their hosts. They have

less often been considered as invasive species in their own

right, although they must frequently be translocated with

their hosts. Blackburn and Ewen follow by reviewing the

evidence that parasites do indeed influence invasions by

their hosts, and consider what determines parasites suc-

cessfully becoming alien invasive species. They conclude

that there is not much evidence pertaining to either issue,

but what evidence there is can be used to draw conclusions

about the impact of parasites on translocations.

Bumblebees play a key role in ecosystem health

through the pollination services they provide. Unfortu-

nately, bumblebee populations are in regional and global

decline. Bumblebee reintroductions can help to reverse this

EcoHealthDOI: 10.1007/s10393-017-1212-6

In This Issue

� 2017 International Association for Ecology and Health

situation, but need to consider the impacts that parasites

can have on them. Here, Brown et al. show that explicitly

considering parasites can maximize the health of bees and

their ecosystems during reintroductions. Their work sug-

gests that processes devised for vertebrates can be used to

aid invertebrate reintroductions and make recommenda-

tions on ways to maximize their success.

Using four case examples, Vaughan-Higgins et al.

describe how biosecurity was applied in practical conser-

vation translocation scenarios prior to translocation, dur-

ing and after a translocation. They implemented

biosecurity, including quarantine barriers at specific points

in the translocation pathway where hazards, identified by

the disease risk analysis, had the potential to induce disease.

Evidence that biosecurity protected translocated and

recipient populations included a reduction in mortality

associated with endemic parasites and an absence of mor-

tality associated with high-risk non-native parasites.

Biosecurity protocols for conservation translocations

should be continually updated in response to findings from

disease risk analysis and post-release disease surveillance.

Factors that influence survival of translocated individ-

uals are often not well understood. California condors are

critically endangered, and recovery of their wild population

is primarily due to translocations from captively bred stock.

Bakker et al. found that as condor flocks grow, released

individuals are increasingly expressing behaviors typical of

wild condors, which increase their encounter rates with

threats and put them at higher risk of mortality. Their

findings illustrate that the survival of translocated animals is

likely influenced by changing behaviors through time,

especially for social animals such as California condors.

Through PCR-sequencing methods, Peniche et al.

analyzed cestodes found in captive and free-living dormice

fecal samples to determine whether a parasite found in a

captive dormouse destined for reintroduction was naturally

present in the wild. A molecular match from captive dor-

mice showed a close relationship to Hymenolepis micros-

toma and a Rodentolepis species. Rodentolepis straminea was

identified in free-living dormice, and since free-living and

captive cestodes were different species, the cestodes in the

captive dormice must be eliminated before reintroduction.

During translocation programs, wildlife is often treated

for parasites in an ad hoc fashion, without a clear rationale.

In this paper, Northover et al. use a field experiment to

measure the effects of Ivermectin treatment on parasite

load and body condition of translocated woylies (Bettongia

penicillata). A single subcutaneous dose of Ivermectin sig-

nificantly reduced Strongyloides-like egg counts in woylies

one month post-translocation. They observed no effect of

treatment in other target or non-target gastrointestinal

parasites and found no benefit of treatment to host health.

Instead, translocation-induced perturbations to population

density were influential in driving parasite abundance and

shaping host health. Hing et al. detail the threats of

translocation in the future survival of these endangered

Australian marsupials. Hing et al. measured fecal cortisol

metabolites (FCM), stress physiology indicators before,

during, and after translocation and found that FCM con-

centration was higher after translocation in both translo-

cated woylies and residents at destination sites. In addition,

body condition decreased with increasing FCM after

translocation. These patterns, which may be important to

consider in conservation management, could be indicative

of translocation stress or stress associated with other fac-

tors.

Despite numerous reintroduction and translocation

programs of Eurasian beavers throughout Europe, there is

no published information regarding a One Health ap-

proach for this species or the scientific outcome of moni-

toring such translocations. Goodman et al. describe the

veterinary health surveillance outcomes following input

from the other ‘one health’ partners. These outcomes relate

to 16 wild-caught Norwegian beavers (Castor fiber) released

to Scotland from 2009 and monitored over a five-year

scientific trail. Two main outcomes discussed are the

mortality events and the release of parasites endemic to

beavers together with their hosts. A challenge faced by

managers working to arrest species declines is making

decisions about which management actions to implement,

given uncertainty about system function. Converse et al.

describe a meta-population model for evaluating actions to

address decline of an amphibian due to the global pan-

demic chytridiomycosis. They demonstrate the inclusion of

both demographic and evolutionary processes in the

model, and evaluate both translocations and efforts to re-

duce the spread of the organism that causes chytridiomy-

cosis. Nichols et al. conclude this Special Feature,

discussing the kinds of decisions that pre- and post-release

disease monitoring can inform, and describe monitoring

methods that can provide such information. Monitoring of

animal populations is not a stand-alone activity but is best

viewed as a component of a larger program of science or

conservation. Conservation programs are developed

around their objectives, and one objective of most animal

translocation programmes is minimization of disease risk.

In This Issue

Tiptoeing Cautiously Yet Confidently: Health Considerationsfor Conservation Translocations

Axel Moehrenschlager1,2

1Centre for Conservation Research, Calgary Zoological Society, 1300 Zoo Road NE, Calgary, AB T2E7V6, Canada2Chair, IUCN Species Survival Commission Reintroduction Specialist Group, Calgary, Canada

The Lion, the Fox and the Ass entered into an

agreement to assist each other in the chase. Having

secured a large booty, the Lion on their return from

the forest asked the Ass to allot his due portion to each

of the three partners in the treaty. The Ass carefully

divided the spoil into three equal shares andmodestly

requested the two others to make the first choice. The

Lion, bursting out into a great rage, devoured the Ass.

Then he requested the Fox to do him the favor to

make a division. The Fox accumulated all that they

had killed into one large heap and left to himself the

smallest possible morsel. The Lion said, ‘‘Who has

taught you, my very excellent fellow, the art of

division? You are perfect to a fraction. He replied, ‘‘I

learned it from the Ass, by witnessing his fate.’’

(Aesop’s Fables: ‘The Lion, The Fox, and The Ass’)

Choices can be empowering, enabling, and inspiring.

Choices can also be tormenting, stagnating, and terrifying.

As beneficial stakes increase, or disastrous possibilities

multiply, the relative exuberance or agony amplifies. What

ultimately drives decisions and outcomes, especially when

consequences are highly uncertain?

We can look to Aesop’s fox for answers. Faced with

spoils of great benefit and an even greater risk of predation,

he reflects on previous experience to make an informed—

seemingly counterintuitive—decision. He chooses minimal

benefit when confronted with outrageous risk. What if the

risk he was weighing also involved starvation? Now, sur-

vival would depend both on the risk of action, as he vies for

a portion of the booty, and the risk of inaction, as he might

starve if he fails to secure anything.

Published online: August 26, 2016

Correspondence to: Axel Moehrenschlager, e-mail: axelm@calgaryzoo.com

EcoHealth 14, S167–S170, 2017DOI: 10.1007/s10393-016-1155-3

Cover Essay

� 2016 International Association for Ecology and Health

With this conundrum, we transition to the conserva-

tion stage. Here, the actors are humans, making decisions

that may decide the fate of other species, and possibly affect

themselves. The stakes may be high, ultimately making

choices that could decide the persistence or extinction of

species and their related ecological functions, evolutionary

potential, and ecosystem services. But what if the well-in-

tentioned actions to fight extinction might harm the very

species that humans try to save? What if conservation ac-

tions bear tremendous risks to the health of individuals, of

populations, of other species, of receiving ecosystems, or of

humans themselves? Will humans act and possibly save

species from extinction, or choose not to act for fear of

greater harm than benefit?

Such scenarios are not hypothetical mind games any-

more; they are blatantly real and increasingly frequent. Like

an emergency room doctor, the conservationist is some-

times presented with suffering species that have no clear

diagnosis; moreover, time is often insufficient to study all

parameters before some interventionistic assistance must be

attempted.

CONSERVATION TRANSLOCATIONS ARE

POWERFUL…IN BENEFIT AND RISK

In the medical kit of treatments to biodiversity challenges,

among the most direct, sometimes desperate, and arguably

powerful tools are conservation translocations which ide-

ally result in self-sustaining populations (IUCN 2013).

Using captive bred and/or wild populations for transloca-

tion, a practitioner can attempt to right past wrongs, to

reduce extinction likelihood, restore ecological function, or

increase ecosystem resilience. Beyond ecology, such actions

may return species to places where humans have missed

them because of their uniqueness, beauty, utility, tradi-

tional meaning, cultural value, or spiritual significance.

These conservation actions are potentially applicable for

any species on Earth, as they include not just population

restorations through reintroduction and reinforcement

within the indigenous range of species, but also more risky

conservation introductions such as ecological replacements

and assisted colonization outside of the indigenous range

(IUCN 2013).

Indeed, the species diversity, frequency, and geo-

graphic distribution of conservation translocations appear

to be ever-increasing (Seddon and others 2014a; Swan and

others 2016; Brichieri-Colombi and Moehrenschlager, in

press). The drivers of this ongoing trend are difficult to

discern; likely, they reflect in part the maturity of reintro-

duction biology as its own discipline, where increasing

evidence suggests that well-planned and well-managed

conservation translocations are increasingly successful. It is

also likely that imminent and increasing threats to more

species in more places are triggering active conservation

interventions at times where other conservation tools no

longer suffice in isolation. There is little doubt that the

application of conservation translocations will continue to

grow. More species will be moved to more places than ever

before in an attempt to restore populations or ecosystems,

or simply to avert global extinction at all costs. Such actions

will bear increasing promise, and potentially increasing

risks.

WILDLIFE DISEASE RISK ANALYSIS AND

STRUCTURED DECISION MAKING ON THE

FOREFRONT

Among the greatest risks associated with conservation

translocations are issues surrounding the health of con-

servation candidates and any species or ecosystem they

might contact directly or indirectly. At worst, translocated

individuals could be the direct vector or indirect transport

mechanism for parasites that could have devastating, per-

petuating, and potentially irreversible invasive effects at

release sites. However, allowing some symbiotic species

such as beneficial parasites to accompany their hosts may

also be crucial to improve the chances of translocation

success. Within such a mine field of considerations, how

can one proceed cautiously, yet confidently? Two funda-

mental, and potentially linked, tools are Wildlife Disease

Assessments (World Organization for Animal Health &

IUCN 2014) and Structured Decision Making. The former

helps to identify potential issues and processes in a context

that aims to reduce, but not eliminate, risk. The latter helps

to break decision problems into sequential steps which

attach potentially quantifiable estimates of positive or

negative impacts and their respective likelihoods to com-

peting alternatives. Such tools are powerful, perhaps even

essential, for translocation health and disease issues to be

addressed responsibly. But are such metrics the only con-

siderations at play? When the odds of the game are deter-

mined, and before the dice are rolled, how are all thoughts

reconciled within the broader context of the growing and

shifting conservation translocation field?

S168 A. Moehrenschlager

THREE OVERARCHING QUESTIONS OF DISEASE

AND HEALTH RISKS FOR THE PRESENT AND

FUTURE

The gambit of benefit and risk contains more pieces than

health and disease considerations; other major conserva-

tion translocation risks are as follows: (1) risk to source

populations; (2) ecological risk; (3) associated invasion

risk; (4) gene escape; (5) socio-economic risk; and (6)

financial risk (IUCN 2013). Although comprehensive risk

assessments concerning all aspects are called for, the way

that they are interpreted, the appetite for risk among

decision makers, and the magnitude of emerging challenges

yield three broader questions for health and disease con-

siderations in conservation translocations.

(1)Will decisions regarding health and disease accommodate

potentially conflicting considerations of other risk factors?

The potential exists that optimal decisions for disease

risk reduction are not optimal for the reduction of others

risks, but perhaps they can be integrated. For example,

inbreeding depression among the receiving population

might make disease risks associated with potential popu-

lation reinforcement more palatable. Or perhaps, ideal

quarantine periods could be reduced in situations where

behavioural effects from captivity would compromise the

fate of translocation candidates before or after release.

(2) Are current tools regarding health and disease risk

able to deal with the individual and interactive ramifications

of species-diverse mass translocations or species that may

become ‘de-extinct’?

While conservation translocation planning most often

addresses considerations on a species by species basis,

movements are currently afoot to ‘rewild’ ecosystems or even

engineer entirely new ecosystems in the name of conserva-

tion (Seddon and others 2014a). Moreover, the concept of

resurrecting extinct species has become a reality. While

assessing health implications of extant speciesmay already be

challenging, doing so for de-extinction candidates is more

than a necessary precaution: serious disease risk should be a

key consideration that might pre-empt some de-extinction

attempts altogether (Seddon and others 2014b).

(3) What optimal level of risk aversion would allow for

responsible disease and health approaches, without precluding

courageous conservation translocations?

Risk assessments outline the likelihood and impact

different scenarios, but they do not yield an automatic

solution of whether such risks are acceptable. Like beauty,

risk is in the eye of the beholder. Risk tolerance in con-

servation may depend upon the uncertainty associated with

potential outcomes and the likelihood of conflict with

other stakeholders (Meek and others 2015). Does risk tol-

erance of key decision-makers increase or decrease with the

growing likelihood of extinction for particular species?

More and more animals are held in under-resourced

rehabilitation centres or menageries that may be deeply

troubling from a health perspective, but how do we manage

species when such facilities hold some of the last individ-

uals of their kind?

These three questions are pertinent to health and dis-

ease, but they could just as easily be posed in the context of

other conservation translocation risks, or indeed of con-

servation translocations in general.

A PLEA FOR CAREFUL COURAGE

The easiest option in the light of outstanding risk is to do

nothing, but doing nothing is not effective for conserva-

tion. My greatest fear is of fear itself…that risks will throttle

courage and stifle daring action. We cannot afford to stop

trying, to stop succeeding, and to stop experiencing set-

backs. A balance of success and setbacks in conservation

translocations is valuable, because it allows us to learn, and

such learning is perhaps the greatest asset we have to take

on emerging and novel challenges of the future. The wealth

of knowledge we now have regarding disease and health

mitigation has blossomed rapidly, underpinned by coura-

geous innovation and sound science.

Aesop’s fox learned from experience, did not run, took

a chance, and by claiming some prey, succeeded despite

risk. We must continue to be responsible and careful: assess

alternatives, plan goals, pursue objectives, act decisively,

and iteratively evaluate outcomes. Where appropriate, we

must also ensure that conservation translocations harness

their escalating role to help species, ecosystems, and people.

We are in a mass extinction. We must meet the chal-

lenges ahead, for nature and for ourselves. We must be

courageous, persistent, and tenacious. We must continue to

act. Let us not stagnate into fearful inaction.

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