Predicting density dependence of welfare of wild animal populations based on resource access linked to habitat availability and usage

Grantee: Ross MacLeod

Institutions: Liverpool John Moores University, United Kingdom

Grant amount: $159,744

Grant type: Challenge grants

Focal species: House sparrow (Passer domesticus)

Conservation status: Least concern

Disciplines: Ecological modeling, population ecology, animal welfare science

Research location: United Kingdom

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Project summary

This project seeks to adapt a habitat and population model to incorporate welfare and apply it to the study of an abundant and widespread avian species, the house sparrow (Passer domesticus). The researchers propose to utilize a variety of welfare metrics to validate model assumptions, which will then allow them to test assumptions related to the welfare implications of density-dependent population dynamics.

Why we funded this project

We funded this project because it addresses our proposal request very closely and proposes to investigate a key wild animal welfare question using a modeling framework. They are also planning to address their question using an abundant avian species. The project has high potential to inform future work focused on modeling total welfare in a population (i.e., combining both individual welfare and population size), and to create a model that can be replicated in other systems.

Find Ross’ other project, studying wild birds, here.

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Empirical assessment of welfare in wild American mink and Eurasian otters: the effects of intra- and inter-specific population density

Grantees: Lauren A. Harrington, Maria Diez Leon

Institutions: Oxford University, United Kingdom

Grant amount: $162,257

Grant type: Challenge grants

Focal species: American mink (Neovison vison), Eurasian otter (Lutra lutra)

Conservation status: Near threatened

Disciplines: Animal welfare science, community ecology, wildlife management

Research location: United Kingdom

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Project summary

This project seeks to determine whether the welfare of American mink (Neovison vison) is negatively impacted in the presence of high densities of Eurasian otters (Lutra lutra), whether both species’ welfare is compromised at relatively higher densities of conspecifics, and whether there is a seasonality to welfare impacts. The project will also assess whether behavioral time budget shifts in mink are associated with higher chronic stress levels, as a proxy for negative impact on mink welfare. These questions will be addressed by measuring welfare through several different domains, including behavioral (exploratory behavior, vocalizations), physical (body condition, ectoparasite load), and physiological (telomere length, fecal glucocorticoid metabolites and hair cortisol) metrics. 

Why we funded this project

This project has the potential to contribute significant information to the understanding of intra-specific density-dependent welfare and to the understanding of network effects among predator-prey and competitor interactions of wild animals. Its unusually diverse set of welfare metrics will allow for cross-validation, strengthening both this project and other projects applying the same metrics. The investigators each have a strong background in animal welfare and have made efforts to better align their work with  Wild Animal Initiative’s priorities for wild animal welfare, which makes them good candidates to carry forward the validation of these welfare indicators (particularly telomere attrition, which is still relatively immature in its use as a welfare indicator).

Find Maria’s other project, studying European minks, here.

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Social connections and their welfare implications in the wild

Grantee: Alex Thornton

Institutions: University of Exeter, University of Bristol, United Kingdom

Grant amount: $157,962

Grant type: Challenge grants

Focal species: Jackdaws (Coloeus sp.)

Conservation status: Least concern

Disciplines: Animal behavior, ornithology, animal welfare science

Research location: United Kingdom

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Project summary

This project seeks to understand the relationship between welfare and social interactions in wild bird populations. Using historical data, the researchers will also seek insight into how welfare varies among individuals in relation to the social system, early-life experiences, and interactions among individuals. They will also investigate whether social systems might play a role in helping to mitigate some of the negative anthropogenic impacts on welfare.

Why we funded this project

The study findings will help in understanding how wild animals cope with increasing temperatures and the impact of thermal stress on their welfare and health. Notably, previous work has suggested that T3 measurements in ungulates are especially sensitive to thermal stress, and so comparing T3 with other indicators based on different physiological pathways, such as glucocorticoids, could help researchers to diagnose the relative significance of different environmental stressors an animal is facing. The project’s behavioral metrics are also crucial for realizing that potential. A secondary reason for our interest in this project is that it has near-term policy implications, potentially highlighting the value of preserving or promoting specific landscape features for the ecosystem service they offer, in the form of shade, to wild ungulates.

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The impact of winter food provisioning on the welfare of wild urban hedgehogs

Grantee: Julia Nowack

Institution: Liverpool John Moores University, UK

Grant amount: $29,977

Grant type: Seed grant

Focal species: Western European hedgehog (Erinaceus europaeus)

Conservation status: Least concern

Disciplines: Physiology, population ecology, animal behavior

Research locations: United Kingdom

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Project summary

This project will investigate the welfare impacts of supplemental feeding during winter on European hedgehogs. Hedgehogs and other species have adapted to the lack of natural food during the winter by hibernating. Previous research, however, has suggested that hibernation may be interrupted when anthropogenic food sources are available. This project will use biologgers to collect data on winter activity and hibernation, as well as the animals’ use of specially designed feeding stations equipped with miniature thermal imaging devices, which will be used to non-invasively measure eye temperature as an indicator of physiological stress. Welfare assessment will also be supplemented by data on ectoparasite load, body mass, fecal glucocorticoid concentrations, latency to approach a feeding station, and survival rate for adults and juveniles.

Why we funded this project

Food provisioning is a potentially important near-term intervention that is already practiced in some contexts, but usually without data on or a primary interest in its wild animal welfare impacts. We appreciate that this project will use a non-invasive approach with multiple physiological and behavioral indicators to evaluate welfare impacts of supplemental feeding on wild European hedgehogs, including juveniles. The results could have implications for the management of other hibernators with access to supplementary feeding, such as dormice, bears, or chipmunks.

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Validation and efficacy of faecal glucocorticoid metabolites as indicators of animal welfare

Grantee: Miriam Zemanova

Institution: University of Fribourg, Animalfree Research, Switzerland, Oxford Centre for Animal Ethics, United Kingdom

Grant amount: $28,500

Grant type: Small grants

Disciplines: Physiology, animal welfare science

Research location: Switzerland, United Kingdom

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Project summary

One of the central components of the stress response is the production of glucocorticoids (GC). The measurement of glucocorticoid levels in blood serum is therefore often used in animal welfare studies. However, it is not always apparent how valuable these measurements are for understanding stress reactions and their relationship to animal welfare. Moreover, blood sampling causes discomfort and is impossible without restraint or immobilization, which can be harmful to the animal and distort the experimental results. Fecal glucocorticoid metabolites (FGM) may be a suitable non-invasive alternative to blood analysis. While there have been several reviews written on fecal glucocorticoids, no systematic review of their validity as an animal welfare indicator is currently available. Therefore, through a systematic review process, this project seeks to provide an evidence base for the efficacy of non-invasive measurement of stress levels in wild animals using fecal glucocorticoids. Evidence will be compiled from studies that have assessed the correlation between fecal glucocorticoids and at least one other credible animal welfare indicator or factor that may be assumed to lead to impaired welfare. The project also aims to compare the performances of blood and fecal samples to assess stress levels. 

Why we funded this project

This study will review the evidence base for the validity and efficacy of non-invasively obtained glucocorticoid measurements and identify both challenges and best practices for working with fecal samples across multiple animal taxa. This is important because WAI is supporting multiple projects utilizing FGM as a physiological welfare indicator. Invasive measurements of stress, such as blood-based GCs, are disadvantageous because, without proper strategy and training, the stress induced by the sampling procedure can influence the measurement. Therefore, non-invasive measurement techniques are not only better for the animals, but may make the science less expensive and more reliable. Another reason we are supporting this study is that it will help to address a general need for better validation of the link between glucocorticoids and animal welfare, which is related to but conceptually distinct from physiological stress.

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Field tests of bee welfare

Grantee: Vivek Nityananda

Institutions: Newcastle University, United Kingdom

Grant amount: $194,317

Grant type: Challenge grant

Focal species: Buff tailed bumblebees (Bombus terrestris)

Conservation status: Least concern

Disciplines: Animal welfare science, entomology, animal behavior

Research location: United Kingdom

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Project summary

Studying affective states in animals has been a key component towards assessing their welfare. Most studies that have used this approach have focused on vertebrates. Yet, the rapid decline in insect numbers calls out for novel methods to monitor their welfare and measuring their affective states would be an important approach. A few recent papers have indicated the presence of affective states in insects, especially bees. These papers have used judgement bias tests in laboratory settings. Recent findings using an active choice test in our lab have also shown robust evidence of affective states in bees due to changed expectations of rewards. However, there is no research looking at these states in the wild. To address this gap, this project seeks to develop and validate new tests for bee affective states in the wild and use these to assess the welfare of bees in the field.

This project will assess whether environments predicted to induce poor welfare and negative valence for bees– such as ones with poor nutrition or light pollution- induce changes in predicted markers of poor welfare. We will use performances in judgement bias tests and reduced responses to rewards in the wild as behavioral markers of welfare. We will also measure the role of neuromodulators (dopamine, serotonin) by measuring the differences in their expression, and of genes involved in their synthesis pathways, in the brains of wild bees in different environments. Measuring changes in these three different markers across different low-welfare environments will help validate them as measure of bee welfare and develop novel markers for wild bee welfare. They will thus providing vital tools for further biological and environmental research in a variety of pollinators.

Why we funded this project

We are generally excited to support this project because it focuses on a wild insect. Insects are extremely abundant and their welfare is typically neglected. Validating a cognitive judgment bias test that can be implemented in the field for a wild insect would be a powerful step forward.

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Thermal imaging as a non-invasive welfare assessment tool for tracking the impact of environmental stressors across wild animal populations

Grantee: Ross MacLeod

Institution: Liverpool John Moores University, United Kingdom

Grant amount: $29,810

Grant type: Small grants

Focal species: Wild birds

Conservation status: Least concern

Disciplines: Physiology, animal welfare science, population ecology, ornithology

Research location: United Kingdom

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Project summary

This project aims to test and validate a standardized multi-species approach to monitoring physiological stress in wild birds by using thermal imaging cameras to measure the animals’ body surface temperature, which could enable tracking of chronic stress in wild populations facing different levels of environmental stressors. Building on pilot work, the project will focus on wild bird populations to develop a standardized thermal imaging methodology capable of monitoring surface temperature of a wide range of free-living wild animals. The methodology will be validated using bird communities visiting 54 standardized feeding and drinking stations spread across three urban-rural gradients in the UK, to quantify how changes in surface temperature are linked to starvation risk, predation risk, and human disturbance.

Why we funded this project

This approach to measuring wild animals’ physiological stress levels through thermal imaging analysis has great potential for scalable monitoring of large numbers of individuals and is usable for cross-species comparisons. We appreciated that this team was interested in addressing non-anthropogenic causes of suffering in starvation and predation, and in extending their method to other species that tend to be neglected (e.g., wild rodents). This work also relates to the project by Paul Jerem that we previously funded, creating a longer-term relationship between Wild Animal Initiative and project participants.

Find Ross’ other project, studying house sparrows, here.

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Parasites in the city: How is the impact of parasites on wild animal welfare affected by urbanization?

Grantee: Amanda Trask

Institutions: Institute of Zoology (IOZ), Zoological Society of London (ZSL), United Kingdom

Grant amount: $199,941

Grant type: Challenge grant

Focal species: Eastern grey squirrel (Sciurus carolinensis)

Conservation status: Least concern

Disciplines: Infectious disease, population ecology

Research location: United Kingdom

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Project summary

Parasitism is likely a key determiner of wild animal welfare, while rapidly increasing urbanisation presents novel challenges and welfare threats, yet the extent that parasitism and urbanisation impact wild animal welfare, both independently and synergistically, remains a major knowledge gap. An individual’s parasite infection status, and the associated welfare impacts, is dependent on parasite exposure risk and susceptibility. Urbanisation may alter exposure risk, for example through changes to population density and resource distribution, and susceptibility, for example through altered host immune function from exposure to urban stressors. Urbanisation may also compound impacts of parasitism, if chronically stressed individuals are less able to cope with further welfare challenges, resulting in synergistic negative welfare effects. Furthermore, welfare impacts of parasites and urbanisation may vary across sex- and life-stage classes, for example due to hormonal influences and changes in immune function with chronic exposure to urban pollution.

We will address this knowledge gap, using grey squirrels from UK sites across an urbanisation gradient. We will use detailed individual-level data on parasite loads and physical and physiological welfare indicators, collected from dead squirrels killed as part of non-native species management, to determine welfare impacts across sites varying in degree of urbanisation, and across sexes and life stages. Then, we will use behavioural indicators from camera trap data to determine associations between population-level welfare, parasite prevalence and degree of urbanisation. Finally, we will estimate ‘welfare expectancy’ of individuals from different populations using sex- and life-stage specific welfare scores. We will expand on current theory and develop a modelling tool to incorporate demographic and environmental stochasticity in welfare states into population models, to aid prediction of how increasing urbanisation may impact wildlife welfare in the future. This study will provide vital knowledge to aid understanding and prediction of the experience and future responses of wild animals to parasites in the context of increasing urbanization, facilitating design and integration of welfare-friendly urban environments for wildlife.

Why we funded this project

Gray squirrels are abundant, they live in close proximity to humans, and they could benefit from welfare interventions such as wildlife fertility control in the near future. Gray squirrels are not native in the UK, where this study will be conducted, and the welfare of non-native species is generally understudied or undervalued compared with native species of conservation interest. This project provides a special opportunity to take advantage of data from squirrels who are being killed as part of a government program, and to access valuable metrics that are hard to measure non-invasively, thereby creating from their deaths an opportunity to gain valuable insights that could ultimately help other squirrels. In addition to their good range of welfare indicators, we appreciate that this project will consider sex- and age-specific variation in welfare impacts and attempt to estimate “welfare expectancy” at a population level.

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Raman spectroscopy as a novel non-invasive technique to assess wildlife welfare

Grantee: Teresa Romero

Institution: University of Lincoln, University of Portsmouth, United Kingdom

Grant amount: $19,100

Grant type: Small grants

Focal species: Tufted capuchin monkey (Cebus apella)

Conservation status: Critically endangered

Disciplines: Physiology, animal welfare science

Research location: United Kingdom

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Project summary

Steroid hormones are routinely used as biomarkers of stress and can be measured in different biological matrices, such as serum, saliva, feces, and urine. However, commonly used collection methods in wildlife are challenging; the stress they induce in the animals may affect hormone levels and also presents ethical issues. More recently, analysis of hormones accumulated in the hair has emerged as a non-invasive tool for measuring chronic stress in wildlife, but current limitations of hair analyses include variation in cortisol concentrations depending on sample preparation and the amount of hair required for cortisol extraction. This project will test whether Raman spectroscopy, which is suitable for the field and does not require sample pre-treatment, is a better way to use hair samples to assess steroid hormones. The planned methodology will make use of samples of mammalian hair with a known cortisol content using a control technique — liquid chromatography mass spectrometry — for comparison. The samples will be subjected to analysis by Raman to validate the technique and establish a robust analytical methodology for the non-invasive analysis of welfare biomarkers in wildlife.

Why we funded this project

Although this project is focused on development of chemical methods, we expect that the method, if validated, could make glucocorticoid assessment in the hair of wild animals much easier, increasing the future quantity and quality of that type of data. Hair is an especially interesting medium for glucocorticoid analysis because it integrates glucocorticoid levels in the body over time, causing the measurements to be more stable over time and potentially more indicative of baseline welfare, since the values are less sensitive to an animal’s most recent activities.

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Are we making urban wildlife sick?

Grantee: Carl Soulsbury

Institutions: University of Lincoln, United Kingdom

Grant amount: $148,741.43

Grant type: Challenge grant

Focal species: Red fox (Vulpes vulpes) and European hedgehog (Erinaceus europaeus)

Conservation status: Least concern

Disciplines: Animal welfare science, animal behavior, physiology

Research location: United Kingdom

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Project summary

Urbanisation causes profound changes to biodiversity. For many species living in urban areas, there is evidence that urban living leads to greater disease prevalence. It is unclear, however, (a) what factors drive this higher disease prevalence and (b) whether this leads to poorer wild animal welfare. We propose a study to compare two urban-dwelling species, red foxes and Eurasian hedgehogs, where we will characterize pathogen prevalence, load, and diversity across an urban-rural gradient. This study will be carried out at two scales: firstly, we will link pathogen loads, faecal glucocortoicoids and habitat at the landscape level, allowing us to broadly understand if urbanisation is associated with increased pathogen loads. We will then carry out a second, more detailed data collection where we will combine pathogen data with measures of stress (infra-red thermography, faecal glucocorticoids) and behavioural measures of affective valence (novel object and judgement bias tests). Here, we will link together pathogen loads and different measures of welfare at the individual level. Ultimately, our aim is to test, within each species, whether population differences in health and welfare are explained by environmental stressors arising from urbanisation (e.g., increased human population density and reduced habitat heterogeneity).

Why we funded this project

We appreciate that this project considers specific characteristics of urban environments, as opposed to simply comparing urban environments with rural ones. This way, it has more potential to inform near-term interventions. Plus, the project design humanely allows for animals’ voluntary participation. In addition to using an effective suite of welfare indicators to investigate the impact of different parasite loads on welfare, the combination of cognitive bias testing with non-invasive physiological stress metrics will provide information on the validity of those metrics, which are being used concurrently in other projects.

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Paying to play? Social time allocation, emotional contagion, and social attention as assays of welfare in wild animals

Grantee: Patrick Tkaczynski

Institution: Liverpool John Moores University, United Kingdom

Grant amount: $29,323

Grant type: Small grants

Focal species: Barbary macaque (Macaca sylvanus)

Conservation status: Endangered

Disciplines: Animal welfare science, animal behavior

Research location: Morocco, United Kingdom

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Project summary

For group-living vertebrates, play and grooming have a number of facets that could be potential indicators of positive welfare, but analysis of such behaviors are yet to be put into a formal framework for monitoring wild animal populations. The Middle Atlas region of Morocco hosts one of the largest populations of wild Barbary macaques, an endangered primate species. These animals face a number of environmental challenges that may disrupt positive social experiences, including anthropogenic disturbance, threats from natural and introduced predators, and an extreme climate. Focusing on six different macaque groups with variable group sizes and facing varying degrees of human exposure, this pilot project will use play and grooming behavior to quantify social time allocation, emotional contagion/synchronization, and social attention as potential assays of positive welfare. As human exposure is typically associated with poor health outcomes in wild animals, this pilot project will focus on this specific environmental challenge to help validate our assays, which can later be applied to examine how positive welfare varies across different gradients, such as climate change or variation in predator pressure. 

Why we funded this project

Most animal welfare research is focused on minimizing suffering, but it’s also vital to maximize positive experiences. The links between positive welfare and evolutionary fitness are also less obvious than for negative welfare, where factors like poor health seem to be associated with both poor welfare and low evolutionary fitness. Because more research focuses on fitness than welfare, the unclear relationship between fitness and positive welfare has contributed to the neglectedness of indicators of positive welfare. This project was one of the few we received that addressed the theme of positive welfare, and we hope that this pilot in primates will provide information to support similar studies in other social species.

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Developing an approach for assessing the welfare of wild birds through the use of bioacoustics analysis

Grantees: Luiza Figueiredo Passos

Institution: Liverpool John Moores University, United Kingdom

Grant amount: $29,060

Grant type: Small grants

Focal species: House sparrow (Passer domesticus)

Conservation status: Least concern

Disciplines: Animal welfare science, ornithology, population ecology, animal behavior

Research location: United Kingdom

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Project summary

Vocalisations carry emotional, physiological, and individual information, suggesting that they can serve as potentially useful non-invasive indicators for inferring wild animal welfare. Communication of affective states via vocalization is due to changes in emotions leading to deviations in the nervous system, causing physiological changes within the vocal production systems. Modern sound analysis techniques have provided tools to discriminate, analyze, and classify specific vocalizations, permitting them to be used for monitoring welfare of different farm and laboratory animals. However, this approach lacks validation for wild individuals. This proposal aims to use passive acoustic monitoring to record wild bird calls at different locations in urban, rural, and conservation-managed areas in the UK. This project will follow a comparative approach to identify vocal patterns and chorus characteristics related to different environmental risks (starvation risk, predation risk, human disturbance, etc.) so that these vocal signatures can be used to infer the welfare status of local bird populations across different environments. The focal species will be one of Europe’s most common species, the house sparrow (Passer domesticus). House sparrows provide an ideal first validation as the species has undergone a massive population decline in many parts of its range over the past 50 years, suggesting that its local populations are facing significant welfare challenges. Validating acoustic monitoring as a tool for non-invasive welfare monitoring in the wild for the first time will provide the basis for future application to birds in general, providing a method that could be used to monitor welfare and changes in welfare of wild birds at any location globally.

Project objectives

Objective 1: Evaluate how changes in sparrow welfare driven by changes in risk of starvation can be indicated by changes in the vocal signatures of local populations.

Objective 2: Understand relationship between predation risk driven changes in sparrows’ welfare and the vocal signatures of local populations.

Objective 3: Impact of human disturbance on sparrows’ welfare.

Why we funded this project

This project is very similar to projects by Claudia Wascher and Sam Reynolds. As stated, bioacoustic monitoring is an extremely promising approach because it is minimally invasive and inexpensive. However, it still needs to be validated, and given its potential future value, we felt that it would be best for it to be validated by at least two independent studies. This project was especially appealing because it focuses on such a ubiquitous species (the house sparrow) and is led by a researcher with a strong record in bioacoustics and an understanding of animal welfare science.

Find Luiza’s other project, studying wild newts, here.

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Developing an automated cognitive bias task for wild squirrels

Grantees: Vikki Neville and Lisa Leaver

Institutions: University of Bristol, University of Exeter, United Kingdom

Grant amount: $157,049

Grant type: Challenge grant

Focal species: Grey squirrel (Sciurus carolinensis)

Conservation status: Least concern

Disciplines: Animal welfare science, physiology, animal behavior

Research location: United Kingdom

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Project summary

The development of the cognitive judgment bias (CJB) task for non-human animals revolutionised the field of animal welfare. The CJB task: (a) is thought to measure both relatively better and relatively poorer welfare across the full spectrum of possible welfare states, (b) is non-invasive, and (c) has been validated using a meta-analytic approach. Moreover, the theoretical basis of the predictions for the CJB task should be applicable across taxa and, accordingly, it has been used successfully in many species. However, to date, its use has largely been in captive species and there are a dearth of examples in wild animals. A key barrier to implementation is that it is difficult to train animals to associate stimuli with particular outcomes: the time needed to do so makes these studies unsuccessful or infeasible in non-captive populations of animals. We propose that this could be overcome by capitalising on the natural behaviour of a species to reduce training time and by using equipment that allows automation of stimulus presentation and data collection.

The main aim of our proposed project is to develop a CJB task for use in wild animals, in particular wild squirrels. Our key objectives are to develop a task for collecting CJB data from grey squirrels which: (1) capitalises on their innate behaviour, obviating the need for extensive training, and (2) makes use of Raspberry Pi equipment so that the task can be easily implemented by other researchers and straightforwardly adapted for use across species to measure welfare and validate novel potential measures of welfare.

To assess that our task works as anticipated, secondary objectives will be to: (1) assess how CJB varies with task manipulations designed to alter affective valence (the distance of the equipment from cover, and levels of food provisioning in the environment), and (2) assess how CJB correlates with other potential non-invasive indicators of welfare (e.g. flight distance in response to humans, QBA scores, retrapability, social status, hair cortisol concentration, and fluctuations in eye temperature following positive and negative stimuli on the judgement bias test measured using infrared thermal cameras).

Why we funded this project

As noted above, cognitive bias tests are generally considered to be exceptionally robust welfare indicators, while gray squirrels are an abundant species and a prime target for near-term interventions. Therefore, we are excited to support the development of a cognitive judgment bias test for use on free-living gray squirrels, which will also help to assess the validity of simpler indicators, such as eye temperature and flight initiation distance.

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Assessing animal welfare from bioacoustic monitoring in red-billed choughs (Pyrrhocorax pyrrhocorax)

Grantees: Claudia Wascher

Institution: Anglia Ruskin University, United Kingdom

Grant amount: $18,679

Grant type: Small grants

Focal species: Red-billed chough (Pyrrhocorax pyrrhocorax)

Conservation status: Least concern

Disciplines: Animal welfare science, ornithology, population ecology, animal behavior

Research location: United Kingdom

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Project summary

In principle, animal vocalizations can be used to identify both positive and negative experiences. Specific vocal characteristics (e.g., mean fundamental frequency) and the rate of occurrence of certain call types can help to quantify animal welfare and are well-established in farm animals such as pigs, horses, cows, and chickens. But although bioacoustic monitoring is a well-established method in captive animals, the method has not been used in wild animals to assess positive and negative emotional states. This project will assess and validate the use of passive bioacoustic monitoring to assess welfare in a reintroduced population of red-billed choughs. The researchers will conduct a combination of automatic acoustic monitoring using “passive” acoustic recorders and direct observations (recording behavior via videos, monitoring activity during the night with night vision scopes, and “active” acoustic monitoring using high-quality directional microphone and parabolic dish). Their approach will allow them to record vocalizations and behavior during natural events expected to influence welfare, such as anthropogenic noise, predation events, intraspecific aggression, resting, or affiliative behaviors. 

Why we funded this project

This project will help to validate the use of passive acoustic monitoring to assess welfare states from variation in vocal behavior, which presents a non-invasive, cost-effective tool to assess the impact of positive and negative events on animal welfare. In theory, acoustic monitoring could be used to assess the welfare of a large number of individuals at a time, making it a particularly promising method to investigate.

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Validating the use of cognitive bias to assess affective valence in wild bird populations.

Grantees: Oliver Burman

Institutions: University of Lincoln, United Kingdom

Grant amount: $193,684.17

Grant type: Challenge grant

Focal species: Free-living wild birds, including (but not limited to): blue tits (Cyanistes caeruleus), great tits (Parus major), wrens (Troglodytes troglodytes), coal tits (Poecile ater), European robins (Erithacus rubecula), chaffinches (Fringilla coelebs), greenfinches (Chloris chloris), starlings (Sturnus vulgaris), blackbirds (Turdus merula) and Eurasian jays (Garrulus glandarius).

Conservation status: Least concern

Disciplines: Animal welfare science, ornithology, animal behavior

Research location: United Kingdom

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Project summary

Cognitive bias is a robust and validated measure of affective valence effective in a wide variety of animal species. However, this valuable approach has been primarily focused on the welfare assessment of captive animals and has not yet been demonstrated in wild free-living animal populations. This goal is crucial for addressing urgent contemporary issues such as the impact of anthropogenic and climatic change on wild animal welfare and to tackle key conservation challenges. In the first attempt to apply a cognitive judgement bias task in a free-living wild animal population, we found that wild birds struggled to complete the necessary training (discrimination) stage of the cognitive bias task. In the proposed project, our aim is therefore to validate two novel cognitive approaches to assessing affective valence in wild animals that do not require training, in conjunction with established behavioural and physiological indicators of welfare. Firstly, we will investigate a modified cognitive judgement bias task based on the innate avoidance of naturally occurring aversive prey, using the principle of imperfect Batesian mimicry. Secondly, we will modify and validate a cognitive attention bias task that relies on a spontaneous response to a potential threat. Both tasks will be assessed in populations of wild birds using natural variation in affective valence. Our anticipated outcomes are the development of an effective, validated measure of affective valence applicable to wild birds without the need for capture/restraint that can be translated across species; an invaluable tool in the assessment of wild animal welfare in response to a wide variety of environmental challenges.

Why we funded this project

This project’s results are intended to be generalizable to numerous woodland bird species (e.g., tits, wrens, starlings). We also appreciate its creatively humane approach to validation, using innate preferences and natural variation in affective valence, rather than training and experimental manipulation. Plus, the project considers both presumably positive (e.g., food, shelter) and presumably negative (e.g., predator abundance) welfare factors, which further strengthens the validation.

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Measuring health and frailty in wild insects

Grantee: Jelle Boonekamp

Institutions: University of Glasgow, United Kingdom

Grant amount: $63,536

Grant type: Ad hoc

Focal species: Field cricket (Gryllinae)

Conservation status: Least concern

Disciplines: Physiology, entomology

Research location: United Kingdom

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Project summary

From an evolutionary perspective, health and well-being is best expressed in terms of fitness variation, the logic being that animals who are optimally adapted to their local environment should be healthy. Hence, health and fitness are intimately entwined on a conceptual level. Morphological, behavioral, and physiological traits that are predictive of fitness could provide potential biomarkers of health, and such approaches have been developed for many different wild vertebrate species. However, due to their small size and mobility, it has proven exceedingly challenging to follow individual insects longitudinally in the wild, let alone their descendants, to measure individual performance and fitness. Consequently, there is a paucity of literature on wild insect health and well-being.

The aim of this project is to address this knowledge gap by developing a non-invasive frailty index that measures the health of individual insects in their natural habitat and that can be applied across species. Analogizing to frailty indices used in human patients, this project will develop an insect frailty index using relevant traits applicable to many different insect species. In humans, the frailty index is highly predictive of morbidity and remaining life expectancy. Similarly, this project seeks to validate the insect frailty index against mortality and fitness data in an insect population by testing whether “frail” individuals have increased mortality risk and reduced fitness. 

This project is made possible by the work that we have done to establish a long-term field study of a natural population of crickets (WildCrickets.org). Using a network of 140 video cameras, all the adults in the population are longitudinally monitored from their emergence in early spring to their natural death in late summer. All their movements, reproductive behaviors, fights, and predation events are recorded, and fitness is measured by genotyping and counting the number of surviving genetic descendants in the next year.

Why we funded this project

Willingness to investigate the welfare of insects is somewhat rare, as are creative ways to assess their welfare. This project both proposed a potentially usable metric, and has access to an unusually useful resource through the WildCrickets.org project. While any particular approach to assessing welfare in insects is unlikely to work, we are hoping to seed enough approaches and strategies that others take up the call, eventually drawing in enough different approaches to produce usable strategies for assessing insect welfare in the wild. Finally, because many of the project resources were already acquired through other sources, we were to fund exclusively the welfare-focused aspects of the project.

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Improving the welfare of wild and captive animals with integrated in-situ and ex-situ behavioural monitoring

Grantee: Sarah Richdon

Institutions: Bristol Zoological Society, United Kingdom

Grant amount: $30,000

Grant type: Seed grants

Focal species: White clawed crayfish (Austropotamobius pallipes)

Conservation status: Endangered

Disciplines: Animal welfare science, marine biology

Research location: United Kingdom

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Project summary

This project will investigate the welfare impacts of translocating captive-bred white-clawed crayfish (Austropotamobius pallipes) into an existing wild population. Both resident and introduced individuals will be fitted with transponders and marked for behavioral monitoring. To evaluate welfare, the researchers will observe social interactions (e.g. aggressive interactions), behavioral diversity, and the animals’ use of their habitat. For example, emigration of native individuals from the focal habitat may be indicative of intraspecific competition intensified by the translocation. Body condition will also be scored as a metric of health and resource access.

Why we funded this project

We are excited to fund a project focused on the welfare of invertebrates, in this case an aquatic crustacean. The monitoring methods and some findings of this project may also be applicable to other aquatic taxa. Translocation is already a commonly used intervention in conservation, yet its welfare implications are poorly understood. By learning about these, translocation strategies could potentially be improved, and we might gain insights that could be applied to other welfare-motivated interventions.

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How do human activities impair the welfare of highly social fish?

Grantee: Joachim Frommen

Institutions: Manchester Metropolitan University, United Kingdom

Grant amount: $28,960

Grant type: Seed grants

Focal species: The princess of Zambia (Neolamprologus pulcher)

Conservation status: Least concern

Disciplines: Ichthyology, physiology, genetics/genomics

Research location: United Kingdom, Zambia

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Project summary

This project will investigate the welfare of a common fish species in Lake Tanganyika, the princess cichlid (Neolamprologus pulcher), as they are exposed to varying levels of human activity. Across eight populations representing a range of distances to human settlements and shipping routes, the researchers will monitor behaviors indicative of stress or aggression, and measure body condition and the brain tissue expression of five genes involved in stress physiology (glucocorticoid response pathway; crf, cyp11b, gr1, gr2, mr). These welfare indicators will be compared with specific environmental characteristics, including boat noise, water visibility (sedimentary and algal load), human fishing intensity, temperature stress, and structural complexity of the local environment.

Why we funded this project

By focusing on an established model system (cichlids), this project is able to benefit from background knowledge of the species’ ecology and behavior and proceed to more neglected welfare questions, as well as potentially engaging a ready audience of cichlid researchers. An especially interesting component of this project is its investigation of brain gene expression to potentially better understand how stress physiology relates to an animal’s subjective experience.

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Investigating ways to assess and improve the welfare of leopards captured in response to conflict, in Nepal

Grantee: Jessica Bodgener

Institution: University of Kent and Wildlife Vets International, United Kingdom

Grant amount: $16,850

Grant type: Small grants

Focal species: Leopard (Panthera pardus)

Conservation status: Vulnerable

Disciplines: Wildlife rehabilitation, animal welfare science

Research location: Nepal, United Kingdom

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Project summary

Leopards are the most widespread and adaptable of the world’s big cats, occupying a wide variety of habitats ranging from remote rainforests to busy urban centers. In Nepal, the successful recovery of tiger populations is displacing leopards from protected parks and forcing them into more populated areas. Low densities of natural prey in these areas, coupled with an abundance of easily hunted feral dogs around settlements, have resulted in leopards colonizing urban and suburban environments. This has caused an increase in conflict with people, including the predation of farmed animals and occasional human attacks. Organizations responding to conflict events have limited resources and must attempt to balance animal welfare and conservation aims with public safety and sociopolitical demands. This has resulted in an ad hoc approach, with frequent interventions, but little to no opportunity to reflect and evaluate the impact or success of these actions. This project will focus on validating entirely non-invasive post-release monitoring techniques, including photogrammetric assessment of body condition and measurement of hair cortisol from fecal samples, to monitor the impact of translocation of leopards away from conflict areas on their health and welfare. 

Why we funded this project

We funded this project because it addresses two of our research priorities by seeking to validate non-invasive monitoring techniques, including hair cortisol as a measurement of chronic stress (which may be more informative of welfare than short-term measures of stress physiology). Although it focuses on leopards, the validation of these methods should be transferable to other species. The researcher, Jess Bodgener, also seems to have a long-term interest in wild animal welfare, and has genuine partnerships in place to build capacity and regard for wild animal welfare in Nepal.

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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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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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It takes guts to grow in the city: the role of the gut microbiome in the welfare of juvenile urban birds

Grantee: Pablo Capilla-Lasheras

Institution: University of Glasgow, United Kingdom

Grant amount: $59,052

Grant type: Challenge grants

Focal species: Blue tits (Cyanistes caeruleus)

Conservation status: Least concern

Disciplines: Physiology, population ecology, animal welfare science, ornithology, animal behavior

Research location: United Kingdom

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Publications

Reid, R., et al. (2024). The impact of urbanization on health depends on the health metric, life stage and level of urbanization: a global meta-analysis on avian species. Proceedings of the Royal Society B, 291(2027). https://doi.org/10.1098/rspb.2024.0617

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Project summary

Amongst the novel stressors that wildlife face in cities, shifts in diet are prevalent and have negative consequences for welfare, particularly in juveniles. Research clearly shows that juvenile birds in urban habitats have low-quality diets, causing stunted growth and increased early-life mortality. For example, in the UK alone, approximately 30 million blue tits hatch every year in cities, but around 63% of them die as juveniles. This project will study juvenile blue tits and investigate how to improve their welfare in urban areas using an integrative approach that will combine metrics of animal welfare with the study of gut microbiomes. Human and captive animal studies suggest that the gut microbiome composition may contain indicators of an animal’s welfare, but this has received little attention in a wild animal context. This study will combine a physiological welfare indicator (telomere attrition), a behavioral welfare indicator (begging behavior), and other health metrics with a study of juvenile birds’ gut microbiomes to link poor-quality urban diets, gut microbiome composition, and welfare. The project will also test a potential near-term dietary intervention (gut microbiome enrichment) to improve the life experience of juvenile birds growing in urban habitats.

Why we funded this project

Welfare is shaped by, and in turn influences, numerous aspects of an animal’s phenotype. Individual welfare indicators offer only limited insights, but combining indicators across multiple domains is thought to be extremely important for triangulating affective state, or “true” welfare. Because the gut microbiome represents a partially distinct domain, understanding how it relates to welfare could therefore strengthen all of our other indicators when they are used in combination. We were especially interested in this project due to the inclusion of an intervention experiment that could be implemented in the near future. Finally, this project will support an early-career researcher with an interest in wild animal welfare.

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Density-Dependent Welfare in Wild Bird Social Networks: Linking resource distributions with disease dynamics

Grantee: Josh Firth

Institution: University of Oxford, United Kingdom

Grant amount: $99,466

Grant type: Challenge grants

Focal species: Great tits (Parus major), blue tits (Cyanistes caeruleus)

Conservation status: Least concern

Disciplines: Animal behavior, community ecology, infectious disease, population ecology, ornithology, bio/eco-informatics, ecological modeling, animal welfare science

Research location: United Kingdom

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Project summary

This project seeks to understand the interplay among various potential density-dependent drivers of positive and negative welfare impacts to determine net welfare related to aggregation (increased density) in wild birds (two species of tit). Infectious disease transfer and increased competition, both likely to reduce welfare, are expected to be directly related to population density. However, population density also covaries with processes that are potentially beneficial to welfare, such as congregation around areas that provide high nutrition, various social benefits, opportunities for increased cooperation, or access to social information. The study will use long-term datasets to empirically determine how the relationship between population density and individual welfare is shaped by infectious disease, including the density-dependent relationship with disease spread. Additionally, using historical data, the project will test how population density, mediated by social contact, environment, and disease, determines individuals’ body condition and mortality risk. Based on the results of this observational phase of the study, the investigators will then manipulate density experimentally, to test model outputs and determine potential causal links.

Why we funded this project 

This project brings two unique advantages. First, the investigators have access to a population that has been subject to intensive monitoring for decades, meaning that much of the relevant ecological context is known and there is historical data to analyze retrospectively. Secondly, in part due to this long-term monitoring, the birds are tagged and observed at feeding stations equipped with RFID tags/readers that allow for experimental manipulation of the density and identity of birds feeding at particular stations. By empirically testing density-dependent models of welfare, the project could provide an increased understanding of the interplay among population density, infectious disease, and various social and environmental characteristics, and in doing so, identify drivers of welfare in wild birds.

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