A Ten-Stage Protocol for Assessing the Welfare of Individual Non-Captive Wild Animals: Free-Roaming Horses (Equus Ferus Caballus) as an Example.
Abstract: Knowledge of the welfare status of wild animals is vital for informing debates about the ways in which we interact with wild animals and their habitats. Currently, there is no published information about how to scientifically assess the welfare of free-roaming wild animals during their normal day-to-day lives. Using free-roaming horses as an example, we describe a ten-stage protocol for systematically and scientifically assessing the welfare of individual non-captive wild animals. The protocol starts by emphasising the importance of readers having an understanding of animal welfare in a conservation context and also of the Five Domains Model for assessing welfare. It goes on to detail what species-specific information is required to assess welfare, how to identify measurable and observable indicators of animals' physical states and how to identify which individuals are being assessed. Further, it addresses how to select appropriate methods for measuring/observing physical indicators of welfare, the scientific validation of these indicators and then the grading of animals' welfare states, along with assigning a confidence score. Finally, grading future welfare risks and how these can guide management decisions is discussed. Applying this ten-stage protocol will enable biologists to scientifically assess the welfare of wild animals and should lead to significant advances in the field of wild animal welfare.
Publication Date: 2020-01-16 PubMed ID: 31963232PubMed Central: PMC7022444DOI: 10.3390/ani10010148Google Scholar: Lookup
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Summary
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This research introduces a structured ten-step protocol for assessing the welfare of free-roaming wild animals, using horses as an example. This protocol should allow for a systematic and scientific evaluation of wild animal welfare.
Understanding Animal Welfare in a Conservation Context
- The research begins by emphasizing the necessity for readers to grasp the concept of animal welfare in a conservation setting. This foundational knowledge aids in understanding how animals and their environments relate and coexist.
The Five Domains Model for Assessing Welfare
- The study utilizes the Five Domains Model as a tool for assessing welfare. This model significantly aids by providing a comprehensive and holistic approach to understand animals, examining their nutrition, environment, health, behavioural interactions, and mental states.
Species-Specific Information Requirement
- To accurately assess welfare, the paper argues that species-specific information is needed. Such unique data could include anatomy, physiology, behaviour, ecology, and life history. This aids in making nuanced and accurate evaluations at an individual level.
Measurable and Observable Indicators of Animal’s Physical States
- The protocol identifies the need for measurable and observable indicators of an animal’s physical state. This can include various quantifiable characteristics like body condition, wounds, diseases, or behavioural signs.
Identifying Individuals Being Assessed
- The protocol encourages identification of the individual animals being assessed. This can help with creating a more personalized evaluation, considering each animal’s conditions and life circumstances.
Selection and Validation of Methods
- The paper describes the selection of appropriate methods for measuring and observing physical indicators of welfare. It also speaks about the scientific validation of these indicators, ensuring the reliability and relevancy of the accepted measures.
Grading of Animal Welfare
- An essential aspect of the protocol is the grading of animals’ welfare states and assigning a confidence score. It helps in understanding the gradation of wellness and the uncertainty tied to each grade.
Assessing Future Welfare Risks
- The last step of the protocol involves evaluating future welfare risks and how these can inform management decisions. This predictive evaluation aids in proactive management, potentially preventing adverse welfare issues before they arise.
Impact on the Field
- By applying this ten-stage protocol, biologists can scientifically assess the welfare of wild animals. This should result in significant progress in the field of wild animal welfare, informing better management practices, conservation efforts, and policy decisions.
Cite This Article
APA
Harvey AM, Beausoleil NJ, Ramp D, Mellor DJ.
(2020).
A Ten-Stage Protocol for Assessing the Welfare of Individual Non-Captive Wild Animals: Free-Roaming Horses (Equus Ferus Caballus) as an Example.
Animals (Basel), 10(1).
https://doi.org/10.3390/ani10010148 Publication
Researcher Affiliations
- Centre for Compassionate Conservation, Faculty of Science, University of Technology, Sydney, NSW 2007, Australia.
- Animal Welfare Science and Bioethics Centre, School of Veterinary Science, Massey University, Palmerston North 4474, New Zealand.
- Centre for Compassionate Conservation, Faculty of Science, University of Technology, Sydney, NSW 2007, Australia.
- Animal Welfare Science and Bioethics Centre, School of Veterinary Science, Massey University, Palmerston North 4474, New Zealand.
Conflict of Interest Statement
The authors declare no conflict of interest.
References
This article includes 139 references
- Kirkwood J.K., Sainsbury A.W., Bennett P.M.. The welfare of free-living wild animals: Methods of assessment.. Anim. Welf. 1994;3:257–273.
- Finn H.C., Stephens N.S.. The invisible harm: Land clearing is an issue of animal welfare.. Wild. Res. 2017;44:377–391.
- Beausoleil N.J.. Balancing the need for conservation and the welfare of individual animals.. 2014. pp. 124–147.
- Ramp D., Bekoff M.. Compassion as a Practical and Evolved Ethic for Conservation.. BioScience 2015;65:323–327.
- Dubois S., Fenwick N., Ryan E.A., Baker L., Baker S.E., Beausoleil N.J., Carter S., Cartwright B., Costa F., Draper C.. International consensus principles for ethical wildlife control.. Conserv. Biol. 2017;31:753–760.
- Wallach A.D., Bekoff M., Batavia C., Nelson M.P., Ramp D.. Summoning compassion to address the challenges of conservation.. Conserv. Biol. 2018;32:1255–1265.
- Hampton J.O., Hyndman T.H.. Underaddressed animal-welfare issues in conservation.. Conserv. Biol. 2019;33:803–811.
- Fraser-Celin V.-L., Hovorka A.J.. Compassionate Conservation: Exploring the Lives of African Wild Dogs (Lycaon pictus) in Botswana.. Animals 2019;9:16.
- Main D.C.J., Whay H.R., Green L.E., Webster A.J.F.. Effect of the RSPCA freedom food scheme on welfare of dairy cattle.. Vet. Rec. 2003;153:227–231.
- Whay H.R., Main D.C.J., Green L.E., Webster A.J.F.. An animal-based welfare assessment of group-housed calves on UK dairy farms.. Anim. Welf. 2003;12:611–617.
- Korte S.M., Olivier B., Koolhaas J.M.. A new animal welfare concept based on allostasis.. Physiol. Behav. 2007;92:422–428.
- Walker M.D., Duggan G., Roulston N., Van Slack A., Mason G.. Negative affective states and their effects on morbidity, mortality and longevity.. Anim. Welf. 2012;21:497–509.
- Hampton J.O., Teh-White K.. Animal welfare, social license, and wildlife use industries.. J. Wildl. Manag. 2019;83:12–21.
- Finn H.. Legal frameworks for wild animal welfare.. Aust. Environ. Rev. 2019;34:116–119.
- Temple D., Manteca X., Velarde A., Dalmau A.. Assessment of animal welfare through behavioural parameters in Iberian pigs in intensive and extensive conditions.. Appl. Anim. Behav. Sci. 2011;131:29–39.
- Samuel E.K., Whay H.R., Mullan S.. A preliminary study investigating the physical welfare and welfare code compliance for tethered and free-ranging horses on common land in South Wales.. Anim. Welf. 2012;21:593–598.
- Andreasen S.N., Sandøe P., Forkman B.. Can animal-based welfare assessment be simplified? A comparison of the Welfare Quality® protocol for dairy cattle and the simpler and less time-consuming protocol developed by the Danish Cattle Federation.. Anim. Welf. 2014;23:81–94.
- Heath C.A.E., Browne W.J., Mullan S., Main D.C.J.. Navigating the iceberg: Reducing the number of parameters within the Welfare Quality® assessment protocol for dairy cows.. Animals 2014;8:1978–1986.
- Mullan S., Szmaraged C., Hotchkiss I., Whay H.R.. The welfare of long-line tethered and free-ranging horses kept on public grazing land in South Wales.. Anim. Welf. 2014;23:25–37.
- Dalla Costa E., Dai F., Lebelt D., Scholz P., Barbieri S., Canali E., Zanella A.J., Minero M.. Welfare assessment of horses: The AWIN approach.. Anim. Welf. 2016;25:481–488.
- Blatchford R.A.. Poultry welfare assessments: Current use and limitations.. J. Anim. Sci. 2017;95:1382–1387.
- Czycholl I., Büttner K., Klingbeil P., Krieter J.. An Indication of Reliability of the Two-Level Approach of the AWIN Welfare Assessment Protocol for Horses.. Animals 2018;8:7.
- Hockenhull J., Whay H.R.. A review of approaches to assessing equine welfare.. Equine Vet. Educ. 2014;26:159–166.
- Hill S.P., Broom D.M.. Measuring zoo animal welfare: Theory and practice.. Zoo Biol. 2009;28:531–544.
- Whitham J.C., Wielebnowski N.. Animal-based welfare monitoring: Using keeper ratings as an assessment tool.. Zoo Biol. 2009;28:545–560.
- Clegg I.L.K., Borger-Turner J.L., Eskelinen H.C.. C-Well: The development of a welfare assessment index for captive bottlenose dolphins (Tursiops truncatus). Anim. Welf. 2015;24:267–282.
- Kagan R., Carter S., Allard S.. A universal animal welfare framework for zoos.. J. Appl. Anim. Welf. Sci. 2015;18:S1–S10.
- Sherwen S.L., Hemsworth L.M., Beausoleil N.J., Embury A., Mellor D.J.. An animal welfare risk assessment process for zoos.. Animals 2018;8:130.
- Littin K.E., Mellor D.J., Warburton B., Eason C.T.. Animal welfare and ethical issues relevant to the humane control of vertebrate pests.. N. Z. Vet. J. 2004;52:1–10.
- Littin K.E., Fisher P., Beausoleil N.J., Sharp T.. Welfare aspects of vertebrate pest control and culling: Ranking control techniques for humaneness.. Rev. Off. Int. Epizoot. 2014;33:281–289.
- Baker S.E., Ellwood S.A., Watkins R., MacDonald D.W.. Non-lethal control of wildlife: Using chemical repellents as feeding deterrents for the European badger Meles meles.. J. Appl. Ecol. 2005;42:921–931.
- Baker S.E., Sharp T.M., Macdonald D.W.. Assessing animal welfare impacts in the management of European rabbits (Oryctolagus cuniculus), European moles (Talpa europaea) and Carrion crows (Corvus corone). PLoS ONE 2016;11:e0146298.
- Gray M.E., Cameron E.Z.. Does contraceptive treatment in wildlife result in side effects? A review of quantitative and anecdotal evidence.. Reproduction 2010;139:45–55.
- Sharp T., Saunders G.. A Model for Assessing the Relative Humaness of Pest Animal Control Methods.. 2011.
- Beausoleil N.J., Fisher P., Mellor D.J., Warburton B.. Ranking the negative impacts of wildlife control methods may help advance the Three Rs.. ALTEX Proc. 2012;1:481–485.
- Beausoleil N.J., Mellor D.J.. Advantages and limitations of the Five Domains model for assessing welfare impacts associated with vertebrate pest control.. N. Z. Vet. J. 2015;63:37–43.
- Hampton J.O., Cowled B.D., Perry A.L., Miller C.J., Jones B., Hart Q.. Quantitative analysis of animal-welfare outcomes in helicopter shooting: A case study with feral dromedary camels (Camelus dromedarius). Wildl. Res. 2014;41:127–135.
- Hampton J.O., Forsyth D.M., Mackenzie D., Stuart I.. A simple quantitative method for assessing animal welfare outcomes in terrestrial wildlife shooting: The European rabbit as a case study.. Anim. Welf. 2015;24:307–317.
- Hampton J.O., Hyndman T.H., Barnes A., Collins T.. Is wildlife fertility control always humane?. Animals 2015;5:1047–1071.
- Hampton J.O., Jones B., Perry A.L., Miller C.J., Hart Q.. Integrating animal welfare into wild herbivore management: Lessons from the Australian Feral Camel Management Project.. Rangel. J. 2016;38:163–171.
- Hampton J.O., Forsyth D.M.. An assessment of animal welfare for the culling of peri-urban kangaroos.. Wildl. Res. 2016;43:261–266.
- Hampton J.O., Adams P.J., Forsyth D.M., Cowled B.D., Stuart I.G., Hyndman T.H., Collins T.. Improving animal welfare in wildlife shooting: The importance of projectile energy.. Wildl. Soc. Bull. 2016;40:678–686.
- Hampton J.O., Robertson H., Adams P.J., Hyndman T.H., Collins T.. An animal welfare assessment framework for helicopter darting: A case study with a newly developed method for feral horses.. Wildl. Res. 2016;43:429–437.
- Hampton J.O., Edwards G.P., Cowled B.D., Forsyth D.M., Hyndman T.H., Perry A.L., Miller C.J., Adams P.J., Collins T.. Assessment of animal welfare for helicopter shooting of feral horses.. Wildl. Res. 2017;44:97–105.
- Sharp T.M., McLeod S.R., Leggett K.E.A., Gibson T.J.. Evaluation of a spring-powered captive bolt gun for killing kangaroo pouch young.. Wildl. Res. 2015;41:623–632.
- Allen B.L., Allen L.R., Ballard G., Drouilly M., Fleming P.J.S., Hampton J.O., Hayward M.W., Kerley G.I.H., Meek P.D., Minnie L.. Animal welfare considerations for using large carnivores and guardian dogs as vertebrate biocontrol tools against other animals.. Biol. Conserv. 2019;232:258–270.
- Hing S., Hampton J.O., Gibson T.J.. Animal welfare and the killing of wildlife by captive bolt in Australia.. Aust. Zool. 2019;40:170–180.
- Mellor D.J., Reid C.S.W.. Concepts of Animal Well-Being and Predicting the Impact of Procedures on Experimental Animals.. 1994. pp. 3–18.
- Mellor D.J., Patterson-Kane E., Stafford K.J.. The Sciences of Animal Welfare.. 2009.
- Mellor D.J., Beausoleil N.J.. Extending the ‘Five Domains’ model for animal welfare assessment to incorporate positive welfare states.. Anim. Welf. 2015;24:241–253.
- Mellor D.J.. Operational details of the five domains model and its key applications to the assessment and management of animal welfare.. Animals 2017;7:60.
- Beausoleil N.J., Mellor D.J., Baker L., Baker S.E., Bellio M., Clarke A.S.. “Feelings and Fitness” Not “Feelings or Fitness”–The Raison d’être of Conservation Welfare, Which Aligns Conservation and Animal Welfare Objectives.. Front. Vet. Sci. 2018;27.
- Green T.C., Mellor D.J.. Extending ideas about animal welfare assessment to include ‘quality of life’ and related concepts.. N. Z. Vet. J. 2011;59:263–271.
- Stafford K.J.. Animal Welfare in New Zealand.. 2013.
- Mellor D.J., Hunt S., Gusset M.. Caring for Wildlife: The World Zoo and Aquarium Animal Welfare Strategy.. 2015.
- Mellor D.J.. Updating animal welfare thinking: Moving beyond the ‘Five Freedoms’ towards ‘A life worth living’.. Animals 2016;6:21.
- Duncan I.J.H.. The changing concept of animal sentience.. Appl. Anim. Behav. Sci. 2006;100:11–19.
- Fraser D.. Understanding Animal Welfare: The Science in It’s Cultural Context.. 2008.
- Broom D.M.. Considering animals’ feeling.. Anim. Sentience 2016;5:1–11.
- Broom D.M.. Sentience and animal welfare: New thoughts and controversies.. Anim. Sent. 2016;57:1–8.
- Ledger R., Mellor D.J.. Forensic use of the five domains model for assessing animal welfare compromise when preparing expert opinions for animal cruelty prosecutions.. Animals 2018;8:101.
- Mellor D.J.. Welfare-aligned sentience: Enhanced capacities to experience, interact, anticipate, choose and survive.. Animals 2019;9:440.
- Beausoleil N.J., Mellor D.J., Stafford K.J.. Validating indicators of sheep welfare.. 2017.
- Panksepp J.. Affective consciousness: Core emotional feelings in animals and humans.. Conscious. Cognit. 2005;14:30–80.
- Murrell J.C., Johnson C.B.. Neurophysiological techniques to assess pain in animals.. J. Vet. Pharmacol. Ther. 2006;29:325–335.
- Boissy A., Manteuffel G., Jensen M.B., Moe R.O., Spruijt B., Keeling L.J., Winckler C., Forkman B., Dimitrov I., Langbein J.. Assessment of positive emotions in animals to improve their welfare.. Physiol. Behav. 2007;92:375–397.
- Denton D.A., McKinley M.J., Farrell M., Egan G.F.. The role of primordial emotions in the evolutionary origin of consciousness.. Conscious. Cognit. 2009;18:500–514.
- Kenward H., Pelligand L., Savary-Bataille K., Elliott J.. Nausea: Current knowledge of mechanisms, measurement and clinical impact.. Vet. J. 2015;203:36–43.
- Mellor D.J.. Positive animal welfare states and encouraging environment-focused and animal-to-animal interactive behaviours.. N. Z. Vet. J. 2015;63:9–16.
- McMillan F.D.. A world of hurts—Is pain special?. JAVMA 2003;223:183–186.
- Gregory N.G.. Physiology and Behaviour of Animal Suffering.. 2004.
- Verbeek E., Waas J.R., McLeay L.M., Matthews L.R.. Measurement of feeding motivation in sheep and the effects of food restriction.. Appl. Anim. Behav. Sci. 2011;132:121–130.
- Verbeek E., Oliver M.H., Waas J.R., McLeay L.M., Blache D., Matthews L.R.. Reduced cortisol and metabolic responses of thin ewes to an acute cold challenge in mid-pregnancy: Implications for animal physiology and welfare.. PLoS ONE 2012;7:e37315.
- Verbeek E., Waas J.R., Oliver M.H., McLeay L.M., Ferguson D., Matthews L.R.. Motivation to obtain a food reward of pregnant ewes in negative energy balance: Behavioural, metabolic and endocrine considerations.. Horm. Behav. 2012;62:162–172.
- Verbeek E., Ferguson D., Lee C.. Are hungry sheep more pessimistic? The effects of food restriction on cognitive bias and the involvement of ghrelin in its regulation.. Physiol. Behav. 2014;123:67–75.
- Ashley F.H., Waterman-Pearson A.E., Whay H.R.. Behavioural assessment of pain in horses and donkeys: Application to clinical practice and future studies.. Equine Vet. J. 2005;37:565–575.
- Gregory N.G.. Physiological Mechanisms Causing Sickness Behaviour and Suffering in Diseased Animals.. Anim. Welf. 1998;7:293–305.
- Fraser D., Duncan I.J.. ‘Pleasures’, ‘pains’ and animal welfare: Toward a natural history of affect.. Anim. Welf. 1998;7:383–396.
- Spinka M., Newberry R.C., Bekoff M.. Mammalian Play: Training for the Unexpected.. Q. Rev. Biol. 2001;76:141–168.
- Held S.D.E., Špinka M.. Animal play and animal welfare.. Anim. Behav. 2011;81:891–899.
- Yeates J.W., Main D.C.J.. Assessment of positive welfare: A review.. Vet. J. 2008;175:293–300.
- Deag J.M.. Behavioural ecology and the welfare of extensively farmed animals.. Appl. Anim. Behav. Sci. 1996;49:9–22.
- Balcombe J.P.. Animal pleasure and its moral significance.. Appl. Anim. Behav. Sci. 2009;118:208–216.
- Spinka M., Wemelsfelder F.. Environmental challenge and animal agency.. 2011. pp. 27–43.
- Yeates J.W.. Naturalness and Animal Welfare.. Animals 2018;8:53.
- Portas T.. Proceedings of the RSPCA Australia Scientific Seminar. Achieving positive animal welfare outcomes in zoos and aquariums, when coping is not enough: Promoting positive welfare states in animals.. 2013. pp. 46–50.
- Littlewood K.E., Mellor D.J.. Changes in the Welfare of an Injured Working Farm Dog Assessed Using the Five Domains Model.. Animals 2016;6:58.
- Beausoleil N.J., Fisher P., Littin K.E., Warburton B., Mellor D.J., Dalefield R.R., Cowan P.. A systematic approach to evaluating and ranking the relative animal welfare impacts of wildlife control methods: Poisons used for lethal control of brushtail possums (Trichosurus vulpecula) in New Zealand.. Wildl. Res. 2016;43:553–565.
- McGreevy P., Berger J., de Brauwere N., Doherty O., Harrison A., Fiedler J., Jones C., McDonnell S., McLean A., Nakonechny L.. Using the Five Domains Model to Assess the Adverse Impacts of Husbandry, Veterinary, and Equitation Interventions on Horse Welfare.. Animals 2018;8:41.
- Clegg I.L.K., Delfour F.. Can We Assess Marine Mammal Welfare in Captivity and in the Wild? Considering the Example of Bottlenose Dolphins.. Aquat. Mamm. 2018;44:181–200.
- McKenzie R.. Australia’s Poisonous Plants, Fungi and Cyanobacteria: A Guide to Species of Medical and Veterinary Importance.. 2012. p. 253.
- Dalla Costa E., Murray L., Dai F., Canali E., Minero M.. Equine on-farm welfare assessment: A review of animal-based indicators.. Anim. Welf. 2014;23:323–341.
- Somerville R., Brown A.F., Upjohn M.. A standardised equine-based assessment tool used for six years in low and middle income countries.. PLoS ONE 2018;13:e0192354.
- Henneke D.R., Potter G.D., Kreider J.L., Yeates B.F.. Relationship between condition score, physical measurements and body fat percentage in mares.. Equine Vet. J. 1983;15:371–372.
- Carroll C.L., Huntington P.J.. Body condition scoring and weight estimation of horses.. Equine Vet. J. 1988;20:41–45.
- Gleerup K.B., Forkman B., Lindegaard C., Andersen P.H.. An equine pain face.. Vet. Anaesth. Anal. 2015;42:103–114.
- Dalla Costa E., Minero M., Lebelt D., Stucke D., Canali E., Leach M.C.. Development of the Horse Grimace Scale (HGS) as a Pain Assessment Tool in Horses Undergoing Routine Castration.. PLoS ONE 2014;9:e92281.
- Hampton J.O., Hyndman T.H., Laurence M., Perry A.L., Adams P., Collins T.. Animal welfare and the use of procedural documents: Limitations and refinement.. Wildl. Res. 2016;43:599–603.
- Linklater W.L., Cameron E.Z., Minot E.O., Stafford K.J.. Stallion harassment and the mating system of horses.. Anim. Behav. 1999;58:295–306.
- Cameron E.Z., Linklater W.L., Stafford K.J., Minot E.O.. Maternal investment results in better foal condition through increased play behaviour in horses.. Anim. Behav. 2008;76:1511–1518.
- Ransom J.I., Cade B.S.. Quantifying equid behavior: A research ethogram for free-roaming feral horses.. 2009.
- Ransom J.I., Cade B.S., Hobbs N.T.. Influences of immunocontraception on time budgets, social behavior, and body condition in feral horses.. Appl. Anim. Behav. Sci. 2010;124:51–60.
- Wemelsfelder F., Hunter E.A., Lawrence A.B., Mendl M.T.. Assessing the ‘whole-animal’: A Free- Choice-Profiling approach.. Anim. Behav. 2001;62:209–220.
- Wemelsfelder F.. How animals communicate quality of life: The qualitative assessment of behaviour.. Anim. Welf. 2007;16:25–31.
- Hintze S., Murphy E., Bachmann I., Wemelsfelder F., Würbel H.. Qualitative Behaviour Assessment of Horses Exposed to Short-term Emotional Treatments.. Appl. Anim. Behav. Sci. 2017;196:44–51.
- Minero M., Dalla Costa E., Dai F., Canali E., Barbieri S., Zanella A., Pascuzzo R., Wemelsfelder F.. Using qualitative behaviour assessment (QBA) to explore the emotional state of horses and its association with human-animal relationship.. Appl. Anim. Behav. Sci. 2018;204:53–59.
- Wemelsfelder F., Hunter E.A., Mendl M.T., Lawrence A.B.. The spontaneous qualitative assessment of behavioural expressions in pigs: First explorations of a novel methodology for integrative animal welfare measurement.. Appl. Anim. Behav. Sci. 2000;67:193–215.
- Keay J.M., Singh J., Gaunt M.C., Kaur T.. Fecal glucocorticoids and their metabolites as indicators of stress in various mammalian species: A literature review.. J. Zoo Wildl. Med. 2006;37:234–244.
- Sherwen S.L., Fanson K.. Validation of an assay to measure glucocorticoid metabolites in the droppings of little penguins (Eudyptula minor). J. Zoo Aquar. Res. 2015;3:134.
- Linklater W., Macdonald E., Flamand J.R.B., Czekala N.M.. Declining and low fecal corticoids are associated with distress, not acclimation to stress, during the translocation of African rhinoceros.. Anim. Conserv. 2010;13:104–111.
- Rakotoniaina J.H., Kappeler P.M., Kaesler E., Hämäläinen A.M., Kirschbaum C., Kraus C.. Hair cortisol concentrations correlate negatively with survival in a wild primate population.. BMC Ecol. 2017;17:30.
- Kalliokoski O., Jellestad F.K., Murison R.. A systematic review of studies utilizing hair glucocorticoids as a measure of stress suggests the marker is more appropriate for quantifying short-term stressors.. Sci. Rep. 2019;9:11997.
- Barnard C.J., Hurst J.L.. Welfare by design: The natural selection of welfare criteria.. Anim. Welf. 1996;5:405–433.
- Klingel H.. Social organization and reproduction in equids.. J. Reprod. Fertil. 1975;23:7–11.
- Grange S., Duncan P., Gaillard J.M.. Poor horse traders: Large mammals trade survival for reproduction during the process of feralization.. Proc. Biol. Sci. 2009;276:1911–1919.
- Garrott R.A., Taylor L.. Dynamics of a feral horse population in Montana.. J. Wildl. Manag. 1990;54:603–612.
- Linklater W.L., Cameron E.Z., Minot E.O., Stafford K.J., Veltman C.J.. Feral horse demography and population growth in the Kaimanawa Ranges, New Zealand.. Wildl. Res. 2004;31:119–1128.
- Harvey A.M., Meggiolaro M.N., Hall E., Watts E.T., Ramp D., Šlapeta J.. Wild horse populations in south-east Australia have a high prevalence of Strongylus vulgaris and may act as a reservoir of infection for domestic horses.. Int. J. Parasitol. Parasites Wildl. 2019;8:156–163.
- Slivinska K., Dvojnos G., Kopij G.. Helminth fauna of sympatric Przwalski’s Equus przewalskii Poljav, 1881 and domestic horses E. caballus L. in the Chernobyl exclusion zone, Ukraine.. Helminthologia 2006;43:27–32.
- Klugh D.. Principles of occlusal equilibration.. 2010. pp. 69–88.
- Dixon P., du Toit N., Dacre I.. Equine dental Pathology.. 2011. pp. 129–147.
- Linklater W.L., Cameron E.Z., Stafford K.J.. Social and spatial structure and range use by Kaimanawa wild horses (Equus caballus: Equidae). N. Z. J. Ecol. 2000;24:139–152.
- Cameron E., Linklater W., Stafford K., Minot E.. Social grouping and maternal behaviour in feral horses (Equus caballus): The influence of males on maternal protectiveness.. Behav. Ecol. Sociobiol. 2003;53:92–101.
- Scorolli A.L., Lopez Cazorla A.C.. Demography of feral horses (Equus caballus): A long-term study in Tornquist Park, Argentina.. Wildl. Res. 2010;37:207–214.
- Beausoleil N.J., Mellor D.J., Stafford K.J.. Methods for Marking New Zealand Wildlife: Amphibians, Reptiles and Marine Mammals.. 2004.
- Mellor D.J., Beausoleil N.J., Stafford K.J.. Marking Amphibians, Reptiles and Marine Mammals: Animal Welfare, Practicalities and Public Perceptions in New Zealand.. 2004.
- Calvo B., Furness R.W.. A review of the use and the effects of marks and devices on birds.. Ring Migrat. 1992;13:129–151.
- Casper R.M.. Guidelines for the instrumentation of wild birds and mammals.. Anim. Behav. 2009;78:1477–1483.
- Walker K.A., Trites A.W., Haulena M., Weary D.M.. A review of the effects of different marking and tagging techniques on marine mammals.. Wildl. Res. 2012;39:15–30.
- Hawkins P.. Bio-logging and animal welfare: Practical refinements.. Mem. Natl. Inst. Polar Res. 2004;58:58–68.
- Hampson B.A., de Laat M.A., Mills P.C., Pollitt C.C.. Distances travelled by feral horses in ‘outback’ Australia.. Equine Vet. J. 2010;42:582–586.
- Silver S.C., Ostro L.E.T., Ma L.K.. The use of camera traps for estimating jaguar Panthera onca abundance and density using capture/recapture analysis.. Oryx 2004;38:148–154.
- Ullas Karanth K., Nichols J.D., Samba Kuma N.. Estimating of Demographic Parameters in a Tiger Population from Long-term Camera Trap Data.. 2010. pp. 145–162.
- Si X., Kays R., Ding P.. How long is enough to detect terrestrial animals? Estimating the minimum trapping effort on camera traps.. PeerJ 2014;2:e374.
- Van Gemert J.C., Verschoor C.R., Mettes P., Epema K., Koh L.P., Wich S.. Nature Conservation Drones for Automatic Localization and Counting of Animals.. 2014.
- Vas E., Lescroël A., Duriez O., Boguszewski G., Grémillet D.. Approaching birds with drones: First experiments and ethical guidelines.. Biol. Lett. 2015;11:20140754.
- Ivošević B., Han Y.-G., Cho Y., Kwon O.. Use of conservation drones in ecology and wildlife research.. J. Ecol. Environ. 2015;38:113–118.
- Linklater W.L., Henderson K.M., Cameron E.Z., Stafford K.J., Minot E.O.. The robustness of faecal steroid determination for pregnancy testing Kaimanawa feral mares under field conditions.. N. Z. Vet. J. 2000;48:93–98.
- Sigurjónsdóttir H., Haraldsson H.. Significance of Group Composition for the Welfare of Pastured Horses.. Animals 2019;9:14.
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