Increasing disease outbreaks and declining biodiversity underscore the need for understanding the impact pathogens have on wildlife populations. To understand how zoonoses impact wild animal welfare, we created a severity index. Using signs of disease information from a bacterial zoonotic disease database, we quantified severity of each sign of disease combined with the number of welfare domains and body systems the pathogen impacts to find the severity index value (SIV) of each unique host-pathogen relationship. We then investigated the effects of host-pathogen richness and conservation status against SIV. We found there to be a strong, negative correlation between increasing pathogen richness and SIV. Species of least concern (LC) were not significantly more likely to have higher SIV than species of conservation concern (CC), but CC species did not have a significant decline of SIV with increasing pathogen richness. This study provides an insight into the relationships between pathogen richness and the risk of pathogen infections to wildlife.

Norway rats (Rattus norvegicus) are considered one of the most significant vertebrate pests globally, because of their impacts on human and animal health. There are legal and moral obligations to minimise the impacts of wildlife management on animal welfare, yet there are few data on the relative welfare impacts of rat trapping and baiting methods used in the UK with which to inform management decisions. Two stakeholder workshops were facilitated to assess the relative welfare impacts of six lethal rat management methods using a welfare assessment model. Fifteen stakeholders including experts in wildlife management, rodent management, rodent biology, animal welfare science, and veterinary science and medicine, participated. The greatest welfare impacts were associated with three baiting methods, anticoagulants, cholecalciferol and non-toxic cellulose baits (severe to extreme impact for days), and with capture on a glue trap (extreme for hours) with concussive killing (mild to moderate for seconds to minutes); these methods should be considered last resorts from a welfare perspective. Lower impacts were associated with cage trapping (moderate to severe for hours) with concussive killing (moderate for minutes). The impact of snap trapping was highly variable (no impact to extreme for seconds to minutes). Snap traps should be regulated and tested to identify those that cause rapid unconsciousness; such traps might represent the most welfare-friendly option assessed for killing rats. Our results can be used to integrate consideration of rat welfare alongside other factors, including cost, efficacy, safety, non-target animal welfare and public acceptability when selecting management methods. We also highlight ways of reducing welfare impacts and areas where more data are needed.

There has been limited research into the effectiveness of penetrating captive bolt (PCB) for stunning horses (Equus caballus) at slaughter. This study observed 100 horses at a commercial abattoir in Mexico, stunned using pneumatic PCB. Animals were assessed at the time of stunning and immediately after for signs of effective/ineffective stunning and shot positioning, with macroscopic gross brain pathology conducted to determine brain trauma. Twenty-five percent (25/100) received more than one shot and 28% (28/100) displayed behavioural signs of ineffective stunning. Of these 28 animals, all had deviations of more than 10 mm from the suggested shot position outlined by the Humane Slaughter Association with rostral-caudal deviation associated with an absence of damage to the thalamus, midbrain, and pons. Forty-four percent (44/100) of animals displayed no damage to critical brain structures (thalamus, midbrain, pons and medulla), with this associated with ineffective stunning. Overall, 16% of shots missed the brain (16/100), with a higher proportion of poll shots (30%) missing the brain compared to frontal shots (12%). There is the potential, when animals are shot into the poll, for paralysis from damage to the spinal cord and caudal brainstem structures. Appropriate position, angle and performance of PCB is therefore vital to achieving an effective stun, by targeting critical brain structures responsible for maintaining consciousness and ensuring proper PCB maintenance. Animals should be routinely checked between stunning and exsanguination, with minimal time between these stages, to minimise recovery of consciousness and alleviate suffering for horses at slaughter.

Monitoring the concentration of glucocorticoid metabolites (GCMs) in faecal samples is a non-invasive tool for physiological stress evaluation, particularly useful when studying wild species. However, both negative and positive stimuli (distress and eustress, respectively) can lead to a rise in glucocorticoids. Thus, besides validating whether GCM concentration in faeces reflects endogenous adrenal activity, we also need to identify behavioural indicators of distress to avoid misinterpretation. Therefore, we submitted four adult male spotted pacas (Cuniculus paca) to an exogenous adrenocorticotropic hormone (ACTH) challenge-test in a Latin square design (4 × 4) to monitor changes in the GCM concentration in faeces. We also aimed to describe behaviours potentially indicative of distress. We collected excreted faeces and video-recorded the animals’ behaviours for five consecutive days, one day before and four days after application of the following four treatments: 1st control (no-handling); 2nd control (intra-muscular [IM] injection of saline solution); low-dose ACTH (IM injection of 0.18 ml ACTH); and high-dose ACTH (IM injection of 0.37 ml ACTH). There was a peak in the concentration of GCM in faeces collected 24 h after the injection of the high-dose ACTH treatment. Additionally, independent of the treatments, spotted pacas spent less time on exploration and feeding states, while spending more time in the inactive but awake (IBA) state following the treatment application (challenge day). The use of GCM concentration in faecal samples together with the behavioural changes (less exploration and feeding, and more IBA) showed to be efficient as a non-invasive tool for welfare assessment of farmed spotted paca.

The successful survival of crocodilian hatchlings is largely dependent upon nest care by females. Nonetheless, it is crucial to understand how environmental degradation affects nest site selection and parental behaviour in female crocodilians. Therefore, our objective was to evaluate the relationship between anthropogenic disturbances and nesting behaviour in free-living broad-snouted caiman (Caiman latirostris). We compared nests in a disturbed and a non-disturbed area, and anticipated differences in nest density, hatching success, female size, egg number and biomass, and parental care behaviour. We monitored 44 nests over four years in Brazil, covering 58.25 km, in a disturbed area (n = 8) and a non-disturbed area (n = 36). According to our findings, nest density was significantly higher in the non-disturbed area (1.31 nests per linear km) compared to the disturbed area (0.25 nests per linear km). However, there was a significantly higher frequency of parental care behaviour (86%) in the disturbed area compared to the non-disturbed area (34%). The other factors studied showed no statistical difference between the two areas. The results indicate that females prefer to nest in healthier, preserved environments, away from anthropogenic disturbances. Yet, presumably at the cost of extra energy expenditure, increased parental care appears to buffer against a reduction in hatching success. Despite the behavioural buffer, the clear preference for non-disturbed nesting and nursery locations underscores the need to identify and protect the remaining non-disturbed areas inhabited by these animals. Our findings suggest that these measures should positively impact the welfare and protection of C. latirostris and other crocodilian species.

Large numbers of decapod crustacea are farmed and harvested globally for human consumption. Growing evidence for the capacity of these animals to feel pain, and therefore to suffer, has led to increased concern for their welfare, including at slaughter. In New Zealand, decapod crustacea are protected by animal welfare legislation. There is a requirement that all farmed or commercially caught animals of these species killed for commercial purposes are first rendered insensible. The aim of this study was to evaluate the efficacy of the Crustastun™, a commercially available bench-top electrical stunner, in two commercially important New Zealand crustacean species; the rock lobster (Jasus edwardsii) and kōura (freshwater crayfish [Paranephrops zealandicus]). Animals were anaesthetised via intramuscular injection of lidocaine and instrumented to record the electrical activity of the nervous system, prior to being stunned according to the manufacturer’s instructions. Stunning efficacy was determined by analysing neural activity and observing behaviour post stunning. All ten P. zealandicus and three J. edwardsii appeared to be killed outright by the stun. Of the remaining J. edwardsii, six exhibited some degree of muscle tone and/or slow unco-ordinated movements of the limbs or mouthparts after stunning, although there was no recovery of spontaneous or evoked movements. One J. edwardsii was unable to be stunned successfully, likely due to its very large size (1.76 kg). None of the successfully stunned animals showed any evidence of return of awareness in the five minutes following stunning. It was concluded that the Crustastun™ is an acceptable method for killing P. zealandicus and for stunning all but the largest J. edwardsii.

Helicopter-based shooting using either a .308 semi-automatic rifle or a semi-automatic 12-gauge shotgun is widely used to manage non-native ungulate populations in Australasia, but the animal welfare outcomes of these two firearms have not been robustly compared. We conducted a randomised field study to compare the animal welfare outcomes of helicopter-based shooting of fallow deer (Dama dama) using a shotgun with three types of lead-based shot (Winchester® 00 Buck, 1 Buck or 4 Buck) relative to a .308 rifle with 135-grain lead-based bullets in New South Wales, Australia, in 2023. All deer that were shot at (n = 390) were killed. Time-to-event curves for times from pursuit to first shot, first shot to insensibility, and the sum of these two metrics (‘total time’), were similar among the four ammunition types. The mean number of shots fired per deer was similar across all four ammunition types, but the mean number of wound tracts per deer increased across the four ammunition types with the number of projectiles per cartridge. All deer subjected to post mortem examination had $ \ge $ 1 wound tract or projectile in the thorax. Our study indicates that using a .308 semi-automatic rifle or a 12-gauge semi-automatic shotgun for helicopter-based shooting of non-native deer, when the latter is used at ranges ≤ 30 m, provides similar animal welfare outcomes.

Globally, millions of animals transition through wildlife rehabilitation facilities annually. Data recorded at these facilities can be used to quantitatively assess factors which result in the animals’ admittance, treatment, release, and survival, and how impacts such as high pathogen avian influenza (HPAI) has altered these parameters. Twenty-five years of records of herring gull (Larus argentatus) admittances into RSPCA Mallydams Wood Wildlife Rehabilitation Centre, Hastings, UK (between 1999 and 2024) were reviewed to determine admission factors and their impacts on the number of days in care and the likelihood of release. Additionally, for the years 1999 to 2010, data were collected on days of post-release survival and distances from the centre travelled from ringed and released birds. During that 25-year period, 17,334 herring gulls were admitted into the Mallydams Centre with 9,013 released, and 2,796 ringed and released between 1999 and 2010. Release rates varied significantly with the category of problem identified at admission. Wild nesting herring gulls, even without the impact of HPAI, have been declining throughout the UK, and the additional anthropogenic pressures on urban gull populations have resulted in a documented national decline in the species. Rehabilitating and returning birds to the wild has shown to be important both for their animal welfare and population, as well as helping identify the impact of HPAI on local urban populations of all relevant species. Results from this research can be utilised to adapt training and resources at rehabilitation centres and determine euthanasia protocols to optimise animal welfare along with release and survival success.

Animal models are a key component of translational medicine, helping transfer scientific findings into practical applications for human health. A fundamental principle of research ethics involves weighing the benefits of the research to society against the burden imposed on the animals used for scientific purposes. The utilisation of wild animals for research requires evaluation of the effects of capture and invasive sampling. Determining the severity and duration of these interventions on the animal’s physiology and behaviour allows for refining study methodology and for excluding or accounting for biased data. In this study, 39 Scandinavian brown bears (Ursus arctos) captured either while hibernating in winter or via helicopter in summer and that underwent surgery as part of a human health project had their movement, body temperature and timing of onset of hibernation compared with those of 14 control bears that had not been captured during the same period. Bears captured in winter and summer showed decreased movement from den exit until late summer, compared to those in the control group. Bears captured in summer showed reduced movement and body temperature for at least, respectively, 14 and 3 days, with an 11% decrease in hourly distance, compared to pre-capture levels, but did not differ in the timing of hibernation onset. We reveal that brown bear behaviour and physiology can be altered in response to capture and surgery for days to months, post-capture. This has broad implications for the conclusions of wildlife studies that rely upon invasive sampling.

Wild orangutans (Pongo spp.) rescued from human-wildlife conflict must be adequately rehabilitated before being returned to the wild. It is essential that released orangutans are able to cope with stressful challenges such as food scarcity, navigating unfamiliar environments, and regaining independence from human support. Although practical skills are taught to orangutans in rehabilitation centres, post-release survival rates are low. Psychological resilience, or the ability to ‘bounce back’ from stress, may be a key missing piece of the puzzle. However, there is very little knowledge about species-appropriate interventions which could help captive orangutans increase resilience to stress. This scoping review summarises and critically analyses existing human and non-human animal resilience literature and provides suggestions for the development of interventions for orangutans in rehabilitation. Three scientific databases were searched in 2021 and 2023, resulting in 63 human studies and 266 non-human animal studies. The first section brings together human resilience interventions, identifying common themes and assessing the applicability of human interventions to orangutans in rehabilitation. The second section groups animal interventions into categories of direct stress, separation stress, environmental conditions, social stress, and exercise. In each category, interventions are critically analysed to evaluate their potential for orangutans in rehabilitation. The results show that mild and manageable forms of intervention have the greatest potential benefit with the least amount of risk. The study concludes by emphasising the need for further investigation and experimentation, to develop appropriate interventions and measure their effect on the post-release survival rate of orangutans.

Growing interest in bat-borne zoonoses has intensified field sampling of wild bats, raising questions about welfare, methodological transparency, and conservation impacts. We conducted a Systematic Quantitative Literature Review of zoonotic research published between 2014–2024 and involving capture and sampling of bats worldwide, querying Scopus and PubMed. A total of 226 studies met the inclusion criteria, spanning five continents and focusing predominantly on viruses (71.2%). Invasive procedures were frequent and often performed on species of conservation concern: euthanasia was reported in 48.2% of studies, anaesthesia in 20.3%, blood sampling in 18.6%, and PIT-tagging in 1.7%. Methodological transparency was frequently insufficient: 46.3% of studies failed to report essential procedural details, preventing assessment of adherence to welfare guidelines, while explicit non-compliance was identified in 15.0% of cases. Less than half of the studies supported their sampling approaches by citing established protocols or guidelines. Ethical approvals and capture or sampling authorisations were generally present, although inconsistently detailed. Overall, our findings reveal substantial gaps in procedural transparency in bat zoonotic research. We encourage the scientific community to strengthen welfare standards and ensure full methodological disclosure within a One Health-One Welfare framework, balancing public health objectives with wildlife welfare and long-term conservation priorities.

Infra-red thermography (IRT) is increasingly being used to estimate physiological stress responses in animals via changes in eye surface temperature. The aim of this study was to determine whether eye temperature of harbour seals (Phoca vitulina) changes in response to routine handling and the potentially painful procedure of flipper-tagging, and if responses to tagging can be mitigated by subcutaneous injection of lidocaine. Orphaned pups (n = 52) at a rehabilitation facility were assigned to one of four treatments: Lidocaine (handled twice, once for injection and once for tagging); Saline (also handled twice); Tag Only (handled once); Sham Tag (handled once). Eye temperature increased more when pups were first handled compared to pups that were not handled and increased further in pups that underwent a second handling. Eye temperature of pups that were tagged without any previous treatment (Tag Only) increased compared to pups that were sham-tagged. Eye temperature also tended to increase after pups were injected with lidocaine but not saline. These results suggest that: (i) handling causes a physiological stress response; (ii) increased eye temperature arising from the second handling suggests the first handling was likely aversive, resulting in sensitisation to further handling; (iii) the rise in eye temperature after tagging, but not sham-tagging, may reflect pain from tagging; and (iv) lidocaine, at the dosage tested, did not appear to reduce the physiological response to tagging. These results show promise for the use of eye temperature to monitor stress responses and for evaluating the potential aversiveness of routine procedures in seals.

Capturing wild birds with mist nets is very common for studying many aspects of avian biology. However, except for adrenocortical reactivity, little is known about other physiological responses to this potentially stressful procedure. Here, we focused on body temperature (Tb) in migratory songbirds, as large numbers are caught for population monitoring and studies of migratory biology. Tb is sensitive to acute stress in other vertebrates and contexts, usually showing an increase (stress-induced hyperthermia). We sampled garden warblers (Sylvia borin), whinchats (Saxicola rubetra) and barn swallows (Hirundo rustica) captured with mist nests using standard protocols at an island stopover site in the central Mediterranean during spring migration. Tb was measured within 3 min (T0), 30 min (T30) and 180 min (T180) from the time the bird hit the net, using an analogue probe inserted into the throat, and a body condition score was calculated for each bird. In the garden warbler, but not the other two species, a slight but significant reduction in Tb occurred after 180 min. In all species, the change in Tb after 3 h of confinement was positively correlated to the change in ambient temperature (Ta) but not to body condition. The mean (± SEM) change in Tb over 3 h was −1.68 (± 0.16)°C for garden warblers, therefore within the expected range of normothermy in small birds. Such reduction in Tb is contrary to the expectation of stress-induced hyperthermia; these results suggest that garden warblers are able to modulate their body temperature and that these small changes are influenced by fluctuations in ambient temperature. Therefore, Tb might not be a good indicator of capture stress in small passerine migrants. Our results also indicate that restraint for ringing procedures is unlikely to have adverse effects on Tb regulation of migratory birds, if held within the time-frame typical of ringing operations.

Kite flying is a popular hobby and sport for children and adults. Despite being illegal in Rio de Janeiro state, Brazil, the use of abrasive threads remains widespread and poses a health risk to both humans and animals. In this study, we analysed the records of 462 magnificent frigatebirds (Fregata magnificens) submitted to rehabilitation centres or found dead along the southern coast of Rio de Janeiro state from October 2016 to August 2020. Of these, 244 individuals (52.8%) presented wing lesions consistent with kite-string injury, which can have a critical impact on the ability of frigatebirds to fly and will ultimately cause their death. Even when veterinary care is provided, only a small proportion of the individuals (2%) will fully recover the ability to fly in order to be released back to the wild. In 2020, an atypical increase in the number of individuals with kite-string injuries (~1,200% increase compared to other years) was noted in the weeks following the suspension of school activities and commerce in response to the COVID-19 pandemic. The number of frigatebirds with kitestring injuries recorded in a given week was positively correlated with internet searches for kite-related terms, which also peaked during the quarantine period of the COVID-19 pandemic. This illustrates how pandemic events may aggravate existing human-wildlife conflicts, and how preparedness plans need to incorporate measures to help communities cope with boredom and isolation during quarantine in ways that do not negatively impact the welfare and conservation of wildlife.

The stranding of cetaceans raises significant welfare and associated logistical issues. A survey of opinions on euthanasia methods based on the recommendations of an International Whaling Commission (IWC) workshop was conducted. Descriptive statistics showed that the workshop recommendations were generally supported and understood, and these included the use of specific euthanasia techniques, but important barriers to adherence were identified, including lack of governmental support, lack of resources, and lack of experienced or trained personnel. Conjoint analysis of factors identified that ‘time to death’ was considered the most important determinant of welfare outcome. In view of the findings of this study, it is recommended that the IWC should consider creating a training programme for responders (both veterinary and non-veterinary) to ensure that trained personnel are available who can implement timely and tailored euthanasia techniques, if required, when strandings occur. Further research on this topic is also advocated to ensure a better understanding of what is being applied in different nations.

The aim of this study was to investigate the relative effectiveness of a rapidly expanding Bonded hunting bullet and an explosively expanding Varmint bullet in young harp seals (Pagophilus groenlandicus). The study was conducted as an open, controlled and randomised parallel-group designed field trial. The animals were pre-randomised (1:1) into one explosively expanding (Varmint) and one expanding (Bonded) bullet type group, with 75 animals in each. The study sample consisted of young, weaned harp seals, 2-7 weeks of age, of both sexes, from the Greenland Sea harp seal population. The study was conducted during the regular hunt. Instantaneous death rate (IDR) and time to death (TTD) were the main variables. The observed IDR was 84% in both bullet groups. Correcting for Weather Condition Index, the IDR for the Varmint bullet was significantly higher compared to the Bonded. The mean TTD was shortest in the Varmint group, but the difference did not reach significance. Compared to the Bonded, a significantly higher total cranial damage score and bleeding intensity, and significantly lower frequencies of bullet exit wounds were detected in the Varmint group. The post mortem reflex movements caused by the Varmint bullet were significantly more powerful with longer duration and higher frequencies of clonic contractions. In conclusion, the results indicate a higher effectiveness of the Varmint bullet relative to the Bonded. The Varmint bullet may thus improve animal welfare in the hunt of young harp seals.

There is a growing demand for civet coffee (also known as ‘Kopi Luwak’ in Indonesia), a luxury coffee produced from coffee cherries that have been eaten and partially digested by civets. Traditionally made using scat collected from the wild, the trend for ‘caged’ civet coffee, where live civets are taken from the wild and housed in captive conditions, is increasing. There is a rapidly expanding civet coffee tourist industry that has emerged within the last five years in Indonesia. The present paper is based on observations of the housing conditions of 48 wild-caught common palm civets (Paradoxurus hermaphroditus) at 16 of these tourist-orientated coffee plantations in Bali. A score between 0-4 indicating welfare concerns was given for eight husbandry factors at each plantation, including: mobility, hygiene, surfaces, shelter, noise, food, water, and social interactions. In addition, interviews were conducted with senior tour guides at each of the plantations to gather information regarding tourist activities and the civet coffee production taking place therein. The data allowed for a welfare assessment to be made, which highlights the inadequate conditions and negative impact on common palm civets associated with the caged commercial production of this luxury product, which are not associated with traditional collection of scat from wild-living civets. We hope that our findings will inform tourists and tour operators about the ethical implications of visiting these attractions.

For animals undergoing rehabilitation it is vital to monitor welfare in a way that is feasible, practical, and limits stress to the animal. The industry gold standard is to assess welfare under the Five Domains model, including nutrition, environment, physical health, and behaviour as the first four physical domains and mental domain as the fifth. Feasibility and effectiveness of these domains for assessing welfare of sea turtles undergoing rehabilitation were reviewed and it was determined that the mental state can be best assessed through behavioural changes. A scoping review of the literature was conducted using Scopus and Web of Science to investigate use of environmental enrichment devices (EEDs) as a measure of welfare in sea turtles. Behavioural assessments using EEDs were found to be well-documented; however, most EED studies pertained largely to livestock or zoo animals. Furthermore, studies rarely concentrated on reptiles, and specifically sea turtles. Results also showed that certain welfare assessment methods may be less appropriate for short-term captivity experienced during rehabilitation. Additionally, the hospital environment limits the ability to address some of the domains (ie biosecurity, feasibility, safety of turtle, etc, might be compromised). This review shows that only three of the nine environmental enrichment strategies described in the literature suit the specific requirements of sea turtles in rehabilitation: feeding, tactile, and structural. It is documented that turtles display behaviours that would benefit from EEDs and, therefore, more specific studies are needed to ensure the best welfare outcomes for sea turtles undergoing rehabilitation.

Free-ranging pet cats (Felis catus) frequently kill wildlife but also return live prey to their owners. This raises welfare concerns if live animals released by cat owners subsequently die, since this is preventable, eg through prompt euthanasia. To estimate the mortality rate of birds released alive by cat owners, we examined the fates of 3,597 cat-attacked individuals submitted to four RSPCA wildlife centres in the UK. Individuals from 64 species were received but most cases (77%) involved just seven species commonly found in urban areas. The overall mortality rate (based on all individuals received at centres, ie including those which perished in transport, those which were euthanased on arrival and those which were admitted for care after having been triaged) was 78%; the post-admittance mortality rate (n = 2,070 birds admitted for care) was 62%. On average, individuals that perished (n = 2,798) survived for 3.0 days before dying or being euthanased. Juveniles were more likely to survive to release than adults, possibly because their small size means they are less likely to receive injuries that are ultimately fatal. Extrapolating from the limited data currently available, and applying conservative estimates at each stage, we estimate that a minimum of 0.3 million birds are released annually by cat owners but subsequently die. Substantial welfare improvements could be achieved if owners were more prepared to adopt strategies to limit hunting behaviour (eg fitting cats with collars and bells) and if owners and rehabilitators were able to effectively identify individuals with fatal injuries. The latter will require studies that quantify the effects of identifiable physical injuries on the likelihood of survival to release, in order to establish effective triage criteria.

Circumstances surrounding advances in stranding response and veterinary care have created a growing need for the long-term housing of captive sea turtles. However, the difficulty in recreating natural conditions in captive settings places a responsibility on caregivers to offset wild-type behavioural deficits with enrichment programming that is, preferably, commensurate with the limitations of each enclosure. Though standardised, multi-institutional behavioural monitoring programmes are currently lacking for marine turtles, facilities housing (or planning to house) sea turtles for the long-term are strongly advised to include ‘wellness’ as a fundamental part of their animal care protocol. Here, concepts of wellness and enrichment in sea turtles are reviewed, and a framework for developing longterm behavioural monitoring programming is provided.