Pre- and Post-release Welfare Indicators for Recovery Programs

Grantee: Laney Hayward Nute

Institution: University of Mississippi, United States

Grant amount: $30,000

Grant type: Small grants

Focal species: Attwater's Prairie-chicken (Tympanuchus cupido attwateri)

Conservation status: Endangered

Disciplines: Wildlife rehabilitation, animal behavior, ornithology

Research location: United States

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Project summary

Captive-raised animals translocated to the wild often suffer high mortality; for example, Attwater’s prairie chickens have had a survival rate of only 17-18% post-release in recent years. The focus of many translocation programs is on investing resources to produce more individuals rather than to improve the welfare of released animals. This project seeks to reduce the stress and suffering of released Attwater's prairie chicken by identifying a set of pre- and post-release indicators of welfare to target individuals for management interventions. Pre-release, the coping styles of individual birds will be identified during routine cage transfers and handling. Following release, the fine-scale movements of released birds will be traced using customized data loggers. By investigating the association of pre- and post-release behaviors with the body condition, daily environment changes, and ultimate survival of these individuals, it will be possible to identify which birds from future releases will need special attention to aid their survival. The researchers hypothesize that individuals with a more proactive (“bold”) personality will disperse further post-release and suffer higher mortality rates compared to more reactive individuals. 

Why we funded this project

Understanding of associations between coping style/personality and welfare outcomes/challenges could be used to predict at-risk individuals in need of interventions such as supplemental feeding, translocation, or medical treatment. For wildlife rehabilitation or “headstarting” programs, coping style associations could also be used to inform rearing protocols to promote resilient styles that result in improved individual welfare in the wild.

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Introducing a novel tool to compare stress levels in captive and wild Macaca fascicularis

Grantee: Vets4welfare

Institution: Vets4welfare Foundation, Netherlands

Grant amount: $20,000

Grant type: Small grants

Focal species: Crab-eating macaque (Macaca fascicularis)

Conservation status: Endangered

Disciplines: Physiology, wildlife rehabilitation, human-wildlife conflict

Research location: Indonesia, Netherlands

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Project summary

This project will compare cortisol concentrations in the hair of Indonesian monkeys (Macaca fascicularis) from three groups: a group whose members have spent their whole lives in the wild, a group that has been kept in captivity for the entertainment industry, and a group that are in the process of rehabilitation following rescue from the entertainment industry. Hair measurements can reflect welfare over a long period, as they integrate cortisol as they slowly grow. The concentration of cortisol in a segment of a hair is thought to reflect the activity of the animal’s physiological stress response at the time that segment was produced. On that premise, the project aims to compare the stress response of M. fascicularis under wild, poor-welfare captive (entertainment), and high-welfare captive (rehabilitation) environments. The hair cortisol data will be compared with veterinary and forensic records and other welfare-relevant observations (e.g., of infections or injuries) where possible. The researchers also intend to determine whether mistreatment in captivity leaves a signal in hair cortisol that could be detected after the fact and used to identify monkeys that have been illegally trafficked. 

Why we funded this project

Although this project focuses narrowly on anthropogenic harms in a particular threatened species, we funded it because their approach is interesting and very similar to one we have been interested in applying to study the welfare of stocked fish (i.e., fish raised in a hatchery and then released into the wild) using biological aging methods, another category of putative welfare indicators that integrate stress over time. Between these two funded studies, we are interested to see 1) how welfare indicators for wild and captive environments of varying quality compare and 2) whether hair cortisol from individuals whose environment changed is consistent (at the corresponding points in time) with that of individuals who were only exposed to one environment or the other. We anticipate that the relationship for the latter question is more complex than described, but investigating it will help us learn more about the validity of hair cortisol measurements and the importance of prior experiences in shaping animals’ stress responses.

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Improving the welfare of translocated individuals - European mink as a case study

Grantee: Maria Diez Leon

Institution: University of London, United Kingdom

Grant amount: $28,965

Grant type: Small grants

Focal species: European mink (Mustela lutreola)

Conservation status: Critically endangered

Disciplines: Wildlife rehabilitation, animal welfare science

Research location: Spain

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Project summary

Conservation breeding programs do not proactively consider or even assess welfare across all stages, nor track the welfare of released individuals. We therefore lack data on how individual welfare state pre-release might affect welfare post-release. This project aims to fill the gap by assessing how levels of two behaviors thought to track positive and negative welfare states — play behaviors and abnormal repetitive behaviors — influence post-release welfare metrics in two on-going reintroduction programs for the European mink, and compare the welfare of released minks to individuals in an established “benchmark” wild population. Fecal glucocorticoid metabolite levels will also be measured to validate these behavioral indicators pre- and post-release. By differentially raising mink in conditions known to improve welfare, the researchers will investigate whether captive environments that promote play and decrease abnormal repetitive behaviors improve pre-release and post-release welfare, whether individual welfare state pre-release correlates with post-release welfare outcomes, and how the welfare of captive-born individuals differs from that of wild-born individuals. 

Why we funded this project

We are interested in the comparison of long-term welfare outcomes between individuals born and protected in captivity and individuals born in the wild, which can help us understand how welfare issues differ between captive and wild environments and how much early-life experiences influence long-term welfare. The project’s objective of identifying improvements for the early-life care of animals who are to be released into the wild also helps us assess “headstarting,” a practice in which juveniles of a species are reared in captivity before being released at a less dangerous life stage, as a near-term intervention for improving the lifetime welfare of animals who have vulnerable juvenile stages but are relatively long-lived as adults. Finally, the applicant has a background in conservation but has demonstrated a long-term interest in wild animal welfare, such as attending an April 2022 workshop on animal sentience (LSE/Rethink Priorities).

Find Maria’s other project, studying American minks and Eurasian otters, here.

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Developing a consensus profile of wild animal welfare: integrating non-invasive monitoring of the gut microbiome with stress physiology and behavior

Grantee: Sam Sonnega

Institution: University of Massachusetts Dartmouth, United States

Grant amount: $29,130

Grant type: Small grants

Focal species: White-footed mice (Peromyscus leucopus)

Conservation status: Least concern

Disciplines: Physiology, animal welfare science, animal behavior

Research location: United States

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Publications

Sonnega, S. and Sheriff, M.J. (2024). Harnessing the gut microbiome: a potential biomarker for wild animal welfare. Frontiers in Veterinary Science, 11. https://doi.org/10.3389/fvets.2024.1474028

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Project summary

This project will characterize the gut microbiome of wild white-footed mice (Peromyscus leucopus) and investigate its relationship with their stress physiology and behavior, including how it changes in response to ecological pressures. While a growing literature from lab-based studies has demonstrated the link between the gut microbiome and regulation of host physiology and behavior, the generality of these findings in ecological contexts remains largely untested. As part of this project, mice will be trapped during different seasons and fecal samples will be collected from which to measure both glucocorticoid concentrations and gut microbiome composition. Concurrently, open-field trials will be conducted to assess individual variation in cognitive bias towards optimism or pessimism (a well-established behavioral indicator of affective state). The mice’s perception of predation risk will also be experimentally manipulated by exposing free-living mice to playbacks of predator noises. By correlating the gut microbiome with both behavioral and endocrine metrics, a consensus profile of the mice’s welfare will be developed that reflects the complexity of their responses to both predictable and unpredictable environmental perturbations, and how those responses can scale up to population and ecosystem level changes via the demographic effects of stress in a so-called “landscape of fear.”

Why we funded this project

We are interested in the development and validation of the gut microbiome as a welfare indicator. Every additional indicator strengthens the interpretation of others, but understanding the gut microbiome may be especially important because it is part of the causal chain linking what is going on in the animal’s brain to fecal metabolites, which are often analyzed as a non-invasive and time-integrated record of physiological stress. This project also links and builds on other gut microbiome research we have funded (by Melissa Bateson, Pablo Capilla-Lasheras, and Davide Dominoni).

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Assessing the Welfare of Wild Olive Baboons (Papio anubis) at the Uaso Ngiro Baboon Project, Laikipia, Kenya

Grantee: Monica Wakefield

Institutions: Northern Kentucky University and Iowa State University, United States

Grant amount: $29,800

Grant type: Small grants

Focal species: Wild olive baboon (Papio anubis)

Conservation status: Least concern

Disciplines: Animal welfare science, animal behavior, primatology

Research location: Kenya, United States

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Project summary

This project aims to assess the welfare of wild baboons using a holistic approach. The study takes advantage of almost 40 years of long-term ecological, demographic, health, and behavioral information on >170 individually known baboons, and will examine how various factors such as age, sex, and social rank correlate with individual welfare measures such as incidence of injury and disease, body mass, and pro-social or agonistic behaviors. The annual scale of the dataset will also enable the researchers to test how events such as droughts have affected welfare during specific periods, and how these effects may have varied according to individual animals’ demographic profiles and biographies.

Why we funded this project

We are excited by this project’s analysis of a long-term longitudinal dataset because of the importance of understanding how wild animals’ welfare varies with demographic factors such as age and sex, as these groups often face different challenges and have different ecological and behavioral requirements, and negative welfare impacts that fall on young individuals may also have ripple effects throughout their lives. We also appreciate this project’s holistic approach. The long-term monitoring means it is possible to consider not only the usual downstream welfare indicators based on health and behavior, but also upstream factors that might influence them, such as social interactions and exposure to predators.

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Assessing the anthropogenic impacts, long-term health, and welfare of elasmobranch species within San Francisco Bay, California

Grantee: Meghan Holst

Institution: University of California, Davis, United States

Grant amount: $19,200

Grant type: Small grants

Focal species: Shark (Selachimorpha sp.)

Conservation status: Near threatened

Disciplines: Animal welfare science, population ecology, community ecology, marine biology, ichthyology

Research location: United States

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Project summary

Individuals belonging to several elasmobranch populations use the San Francisco Bay Estuary during critical periods of their life history. For example, the broadnose sevengill shark (Notorynchus cepedianus) is an apex predator that visits seasonally to pup. Pups then appear to reside in the estuary for several years before they join the adult population that migrates from Alaska to Baja, California. The San Francisco Bay also serves as a major harbor for container and cruise ships. To allow these large vessels to enter the bay, dredging occurs continuously within San Francisco Bay in the primary channel where many of the adult elasmobranchs also reside, potentially increasing contaminant exposure. Additionally, both commercial and recreational fishing occurs on shark species and their preferred prey, posing direct physiological impacts on elasmobranchs and constraints to their prey availability. Little has been done to evaluate potential unrecognized consequences of these activities on the health and welfare of elasmobranch species and the San Francisco Bay ecosystem. To address this gap in knowledge, this project will measure stress physiology and blood contaminants to evaluate whether the health and welfare of elasmobranchs is threatened within San Francisco Bay, and evaluate dietary needs of elasmobranch species within San Francisco Bay to determine whether individuals are threatened with hunger/starvation due to fishing of their preferred prey. Stable isotope analysis of the sharks and potential prey will also be used to more precisely identify their dietary needs and sensitivities, and ultimately map ecological relationships within the ecosystem.

Why we funded this project

We funded this project primarily because it addresses our interest in understanding the welfare implications of ecological system dynamics. The project also focuses on lifestage-specific ecological differences within the focal species, focusing on juveniles, which are the most numerous and often neglected. Additionally, the lead researcher is a PhD student who has an interest in wild animal welfare and has already demonstrated an aptitude for coordinating scientific research projects. The ability to write a compelling proposal at such an early research stage is very promising for their future career prospects.

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The animal welfare of animal warfare: how inter-group interactions affect wild animal wellbeing

Grantee: Dominic Cram

Institution: University of Cambridge, United Kingdom

Grant amount: $29,965

Grant type: Small grants

Focal species: Meerkats (Suricata suricatta)

Conservation status: Least concern

Disciplines: Animal behavior, population ecology, community ecology

Research location: United Kingdom, South Africa

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Project summary

Fierce group conflicts are not uniquely human, and many group-living animals regularly engage in “animal warfare.” These inter-group interactions play an influential role in natural population regulation, yet the health and well-being consequences for those involved remain unclear. Conservation and management interventions are currently developed with little understanding of how large-scale conflict affects welfare in wild animals. Given that anthropogenic habitat loss and climate change could increase the frequency of inter-group battles, there is an urgent need to investigate the welfare cost of animal warfare. This research program will investigate the welfare consequences of intergroup interactions and fights in wild Kalahari meerkats (Suricata suricatta). The project will take advantage of an established dataset of meerkat behavior, body weight, territory use, and reproduction, covering more than 500 inter-group interactions over 14 years. Identifying the short- and long-term welfare implications of inter-group interactions in meerkats will shed light on similar animal warfare in group-living insects, fish, birds, and mammals. Clarifying the circumstances that lead to the most harmful battles will provide a first step in understanding how their frequency could be reduced, which could limit the suffering they cause and enhance the welfare of group-living wild animals.

Why we funded this project

This project addresses a neglected topic related to our research priority of understanding conflicts of interest between wild animal groups. We especially appreciate this project’s holistic approach to welfare assessment, its attention to indirect effects (collateral damage) of animal conflicts in the form of costs to orphaned juveniles and the creation of a “landscape of fear,” and the openness of the investigators to considering interventions that could elevate wild animal welfare above its natural baseline.

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Physiological and behavioral effects of nicarbazin on feral urban pigeons (Columba livia)

Grantee: Jessica X. Wright-Lichter

Institution: Tufts University, United States

Grant amount: $30,000

Grant type: Small grants

Focal species: Urban pigeon (Columba livia domestica)

Conservation status: Least concern

Disciplines: Physiology, ornithology, animal welfare science

Research location: United States

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Project summary

Nicarbazin (NCZ) is an oral contraceptive that has been shown to be effective in feral urban pigeons (Columba livia). However, although it is EPA-approved and widely marketed, no published studies examine the impact of prolonged exposure to NCZ on the pigeons beyond the contraceptive effect. This is concerning because evidence from agricultural use of the compound (where it was originally developed as an antiparasitic drug) suggests that NCZ exposure may limit the ability of birds to cope with high heat. 

To study the impact of NCZ treatment on pigeon welfare, especially as a function of heat exposure, feral pigeons will be treated with NCZ for three weeks before being exposed to increased ambient temperature for four hours to assess their physiological and behavioral responses compared to a control group. This project will use changes in levels of the hormone corticosterone as a physiological proxy for welfare in exposed pigeons. The researchers will also look for behavioral correlations by measuring the onset and frequency of heat-mediating behaviors (e.g., panting, wing-spreading). The behavioral (and plausibly welfare-relevant) effects of NCZ treatment alone will also be assessed by quantifying impacts on affiliative and aggressive behaviors, social status, and access to feed at bait sites.

Why we funded this project

We funded this project because we see wildlife fertility control — particularly applied to urban pigeons — as a highly promising near-term intervention. We are especially interested in indirect welfare effects of fertility control (e.g.,on juvenile welfare and survival), but we have also been concerned by the lack of research on direct welfare impacts. This study will focus on direct welfare impacts while also providing some of the first data on NCZ’s effects on pigeon social dynamics, which are likely to be very important determinants of overall welfare. These data could then be used to guide the application of NCZ contraceptives (e.g., their seasonal timing) to maximize pigeon well-being while successfully controlling urban pigeon populations.

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Development of novel measures of welfare in juvenile European starlings exposed to nutritional stress

Grantee: Melissa Bateson

Institution: Newcastle University, United Kingdom

Grant amount: $60,000

Grant type: Challenge grants

Focal species: Starlings (Sturnidae sp.)

Conservation status: Least concern

Disciplines: Physiology, ornithology

Research location: United Kingdom

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Project summary

Juveniles of passerine species such as the European starling (Sturnus vulgaris) experience massive mortality, much of which is caused by direct or indirect effects of nutritional stress. Of birds that survive, many will bear the “scars” of early-life stress that have consequences for their welfare. The aim of this project is to identify the metabolic “fingerprint” of nutritional stress in starling nestlings and to validate sensitive and non-invasive molecular biomarkers that can be used to assess the welfare of wild starlings.

This group has been developing the hypothesis that biomarkers of biological age not only predict future morbidity and mortality, but also reflect the quality of an animal’s cumulative lifetime experience. Existing metrics of biological age, particularly telomere length, require invasive blood samples, and measurements are imprecise, meaning that large sample sizes are currently required to obtain significant effects in epidemiological studies. Estimating biological age based on measuring multiple age-related biomarkers (as is typical in the human aging literature) is likely to be more reliable than using telomere length alone. 

This project will use untargeted metabolomics to identify multiple novel biomarkers of exposure to nutritional stress in nestling starlings. This “fingerprint” will be validated by testing whether it predicts gold-standard behavioral measures of adult affective experience in a cohort of laboratory-raised birds. Metabolomics measures thousands of small molecules in one biological sample and can be performed on a range of tissues including blood, hair, and urine. The aim will be to identify an applicable panel of metabolites that can be measured cheaply and easily from feathers and the uric acid component of guano.

Why we funded this project

This project should introduce a novel indicator of long-term welfare that is less invasive, requires fewer resources, and is potentially more reliable than similar existing methods. The PI is a world leader in the field of animal behavior and is the main originator of using biological aging to understand long-term animal welfare, especially in non-model species. For that reason, we are especially confident in this work being high-quality and having great academic reach and influence.

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Integrating individual-level juvenile welfare in dynamic habitats across time and space

Grantee: Tom Luhring

Institutions: Wichita State University, Texas State University, and Stephen F. Austin University, United States

Grant amount: $162,604

Grant type: Challenge grants

Focal species: Sirens (Siren intermedia)

Conservation status: Least concern

Disciplines: Herpetology, physiology, climate science

Research location: United States

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Project summary

The project will track individual juvenile lesser sirens (Siren intermedia) within and across years for four populations in Eastern Texas. The lack of a terrestrial life-stage and severely limited overland dispersal ability means that hydrologically isolated pools function as closed populations, facilitating recaptures and simplifying demographic estimates. Siren health is directly impacted by the effects of the environment (e.g., drought conditions) through the impacts of resource availability on body condition and growth rates. Furthermore, sirens show strong size-dependent and seasonal shifts in antagonistic behaviors such as biting which lead to acute injuries. 

Aquatic amphibians are especially well-suited for the collection of water-borne stress hormones (corticosterone), which offer the least invasive method of evaluating an integrated measure of corticosterone levels that are passively being released through the skin, gills, feces, and urine. This project will use water-borne corticosterone release rates to investigate changes in stress physiology as a function of changes in the environment experienced by the individual (population density, drought severity index, water temperature, pH, conductivity) across time and space to understand coping capacity. These data will also be used to investigate the welfare impact of an established marking technique compared to a novel approach based on pattern recognition by a machine-learning algorithm. 

Why we funded this project

Juvenile mortality is especially high in amphibians, and amphibian welfare in general is a neglected subject. This project should provide proof of concept for a cost-effective approach for assessing welfare at both an individual and population level. The waterborne measurements have the potential to integrate corticosterone over a longer period of time, increasing its reliability as a welfare indicator. Finally, this project will test a novel, non-invasive approach to mark-recapture studies, which could facilitate much better individual-level welfare research for amphibians and other (especially aquatic) animals in the future.

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