Species, causes, and outcomes of wildlife rehabilitation in New York State

Rehabilitation outcomes of bird-building collision victims in the Northeastern United States

Building collisions are a leading threat to wild birds; however, only those that are found dead or fatally wounded are included in current mortality estimates, with injured or stunned birds largely assumed to survive long-term. Avian building collision victims are often brought to wildlife rehabilitators for care, with the hopes they can be released and resume their natural lives. We examined the wildlife rehabilitation records of over 3,100 building collisions with 152 different avian species collected across multiple seasons to identify patterns of survival and release among patients. The number of admissions varied by season; fall migration had the highest number of cases and winter had the least number of cases, and summer having the lowest release proportion and winter having the highest. The most common reported injury was head trauma and concussion. Our logistic and Poisson models found that mass had a strong positive effect on release probability, and the season of summer had a strong negative effect on release probability. Mass and winter had a strong positive effect on treatment time, and age and the seasons of fall and winter had a strong negative effect on treatment time in these models. Ultimately, about 60% of patients died in care, either by succumbing to their injuries or by euthanasia. Patients that were released remained in care for longer than patients that died. This study reports different data than carcass studies and views bird-building collisions from the perspective of surviving victims to explore longer-term effects of these collisions on mortality. Increased communication and collaboration between wildlife rehabilitators and conservation researchers is recommended to better understand building collisions and how to respond to this leading threat to wild birds. These findings, along with our estimate of delayed mortality, suggest that overall collision mortality estimates based on carcass collection far exceed one billion birds in the U.S. each year.

Survey of antimicrobial and probiotic use practices in wildlife rehabilitation in the United States

Antimicrobial resistance is a global health concern. As such, there have been increased efforts to monitor and standardize antimicrobial prescribing practices in humans and domestic animals. In contrast, there is relatively little known about specific prescribing practices in wild animals despite the wide use of antimicrobials and other microbial interventions, such as probiotics to treat captive wildlife. Therefore, the goal of this study was to examine current antimicrobial and probiotic use from a cross-section of wildlife rehabilitation facilities in the United States. An anonymous electronic survey was sent to 105 United States permitted wildlife facilities to collect information about admissions, current antimicrobial and probiotic use practices, and current staff knowledge and attitudes surrounding antimicrobial resistance and probiotic effectiveness. Respondents from over 50% of facilities participated in the survey (54/105), including 45 facilities that treated birds. All facilities reported using antimicrobials, including some from groups considered critically important for human medicine, for a wide range of medical conditions and prophylaxis. Among antibiotics, enrofloxacin and amoxicillin-clavulanic acid were the most commonly used. Antifungals were not as widespread, but itraconazole was the most commonly used. Over 75% of respondents said that their facilities would benefit from having standardized antimicrobial guidelines in place. Probiotics were also used in more than 50% of facilities, but there was notable disparity in opinions regarding their efficacy. The results of this survey are a first step towards understanding antimicrobial and probiotic use practices in the treatment of captive wildlife and developing an antimicrobial stewardship program for wildlife rehabilitation.

Causes of admissions and mortality in patients of a wildlife rehabilitation centre in Bulgaria

Wildlife rescue centres are specialised units with ecological, conservational and veterinary medical activities, which include treatment, rehabilitation, breeding and releasing rare and endangered wild animals into their natural habitat, as well as environmental education. These centres provide an opportunity to monitor ongoing ecological changes in wildlife, environmental pollution and emerging diseases. With the present study, we aimed to analyse the causes and conservation status of the largest wildlife rehabilitation centre in Bulgaria. A total of 18,720 patients, from 26 orders with various conservation statuses and different etiology, have been admitted to the rehabilitation centre for over 25 years. The summarised results showed that 40% of the patients were admitted with an unknown etiology and the proportion of anthropogenic causes was 18%. Natural factors related to incidents with wild animals were 32%, while a share of 10% of the wildlife which resided at the WRBC referred to a part of re-introduction programmes. This type of analysis of wildlife rehabilitation centres could provide useful information about the status of populations and ecosystems, as well as support conservation practices.

Wildlife Pediatrics

Injured, sick, and orphaned wildlife neonates arrive by the thousands to wildlife rehabilitation centers, veterinary hospitals, and wildlife hospitals in North America. With the ultimate goal of releasing them back into the wild, veterinarians need to know the ecology, biology, and specific problems encountered by the various species of wildlife.

Trends in Admissions and Outcomes at a British Wildlife Rehabilitation Centre over a Ten-Year Period (2012-2022)

Millions of animals pass through wildlife rehabilitation centres (WRCs) globally each year, some dying in captivity, others euthanised, and some released into the wild. Those caring for these animals are generally well-intentioned, but skills, knowledge, and resources may be limited, potentially compromising animal welfare. WRC databases provide an opportunity to provide an evidence base for treatment and conservation efforts. 42,841 records of animals admitted over a 10-year period to a British WRC were analysed. More birds (69.16%) were admitted than mammals (30.48%) and reptiles and amphibians (0.36%). Most admissions were in the summer (48.8%) and spring (26.0%) months. A total of 9 of the 196 species seen made up 57% of admissions, and hedgehogs were the most common species admitted (14% of all admissions and 20% of mammals). Juvenile animals (35.5%) were admitted more frequently than 'orphans' (26.0%) or adults (26.4%). 'Orphaned' was also the predominant reason for admission (28.3%), followed by 'injured' (25.5%). 42.6% of animals were eventually released back to the wild, 19.2% died in captivity, and 37.2% were euthanised; 1% of outcomes were unknown. The prognosis was better for orphaned animals than for those admitted because of injury. Unexpected natural deaths in captivity were found to decline over the period of study, consistent with improved early triage. These findings can be used to focus veterinary and WRC training and seasonal resources on the species and case types most likely to be successfully rehabilitated and released. The findings also have the potential to contribute to our understanding of anthropogenic impacts, historical and regional variations in ecosystem health, and resultant implications for animal welfare.

A Retrospective Analysis of Admission Trends and Outcomes in a Wildlife Rescue and Rehabilitation Center in Costa Rica

The evaluation of data regarding rehabilitation practices provides reference values for comparison purposes among different rehabilitation centers to critically review protocols and efficiently improve each center. The aim of the present work was to present the main causes of admission to Rescate Wildlife Rescue Center for each taxonomic group, to determine the admission factors that influenced the release and mortality, and to determine the predictive factors of release and mortality of wildlife. To this end, a retrospective study was carried out based on 5785 admissions registered in the database of Rescate Wildlife Rescue Center in Costa Rica in 2020 and 2021. Statistical analysis consisted of sample characterization via the analysis of several categorical variables: species, order, class, age group, cause of admission, outcome, clinical classification and days in the hospital, and respective association with the mortality or release rate. Most of the rescue animals were birds (59.3%), then mammals (20.7%), reptiles (17.4%), and finally 'others' (2.6%). The main causes of admission were 'captivity' (34.9%), 'found' (23.3%), and 'trauma' (19.3%). Animals rescued due to 'captivity' and the classes 'birds' and 'reptiles' had the highest release rates. The causes of admission 'trauma' and 'orphanhood' and the class 'birds' had the highest mortality rates. In general, a greater number of days spent in the hospital and membership in the classes 'reptiles', 'juveniles', in need of 'basic care', or 'clinically healthy' were predictors of survival. In contrast, the age groups 'infant' and 'nestling' were predictors of mortality. These results demonstrate the value of maintaining, improving, and studying databases from wildlife rehabilitation centers, as they can provide useful information that can be used to enhance the allocation of economic resources, treatment methods, disease surveillance, public education, and regulatory decision-making, leading to a better understanding of threats to wildlife and subsequent implementation of conservation actions.

Brief exposure to captivity in a songbird is associated with reduced diversity and altered composition of the gut microbiome

The gut microbiome is important for host fitness and is influenced by many factors including the host's environment. Captive environments could potentially influence the richness and composition of the microbiome and understanding these effects could be useful information for the care and study of millions of animals in captivity. While previous studies have found that the microbiome often changes due to captivity, they have not examined how quickly these changes can occur. We predicted that the richness of the gut microbiome of wild-caught birds would decrease with brief exposure to captivity and that their microbiome communities would become more homogeneous. To test these predictions, we captured wild house sparrows (Passer domesticus) and collected fecal samples to measure their gut microbiomes immediately after capture ("wild sample") and again 5-10 days after capture ("captive sample"). There were significant differences in beta diversity between the wild and captive samples, and captive microbiome communities were more homogenous but only when using nonphylogenetic measures. Alpha diversity of the birds' microbiomes also decreased in captivity. The functional profiles of the microbiome changed, possibly reflecting differences in stress or the birds' diets before and during captivity. Overall, we found significant changes in the richness and composition of the microbiome after only a short exposure to captivity. These findings highlight the necessity of considering microbiome changes in captive animals for research and conservation purposes.

Interrupted Lives: Welfare Considerations in Wildlife Rehabilitation

Each year in the United States, thousands of sick, injured, or displaced wild animals are presented to individuals or organizations who have either a federal or state permit that allows them to care for these animals with the goal of releasing them back to the wild. The purpose of this review is to demonstrate the complexity of considerations rehabilitators and veterinarians face while trying to optimize the welfare of wild animals in need of care and rehabilitation. The process of rehabilitation is inherently stressful for wildlife. Maintaining an animal's welfare during the rehabilitation process-from initial contact and tria+ge to the animal's euthanasia, release, or captive placement-requires deliberate, timely and humane decision making. The welfare of wild animals can be improved by preventing human-related causes of admission, providing resources and support for wildlife rehabilitation (almost all rehabilitation in the United States is privately funded and access to veterinary care is often limited); further developing evidence-based wildlife rehabilitation methods and welfare measures, attracting more veterinary professionals to the field, harmonizing regulatory oversight with standards of care, training, and accountability, and increasing public education.

Conservation through Collaboration: Regional Conservation Programs of the North Carolina Zoo

In response to rapid biodiversity losses in recent decades, zoos have become more engaged in conservation issues. Solutions to conservation challenges are complex and require collaborative efforts across organizations. Zoos can be effective partners that can contribute diverse expertise and resources to protect wildlife and their habitats. While zoos often partner with international organizations to facilitate field-based conservation projects on the exotic animals they exhibit, some of the most meaningful conservation and education initiatives are conducted locally in partnership with local organizations. A core part of the mission of the North Carolina Zoo (Asheboro, NC, USA) is the conservation of wildlife and their natural habitats, both regionally and internationally. The goal of this article is to review the North Carolina Zoo’s regional conservation programs and the importance of partnerships with other local organizations in accomplishing shared goals. North Carolina Zoo plays an important role in regional conservation by protecting and managing natural lands, protecting declining amphibians through headstarting and habitat management, rehabilitating native wildlife, and working on local outreach and sustainability projects to reduce impacts on natural resources and inspire others to get involved in conservation. These programs were developed through partnerships with local and state government agencies, academic institutions, non-profit organizations, other zoos and aquariums, schools, libraries, and businesses. These collaborations have been instrumental in developing and implementing successful projects by pooling limited resources and sharing crucial expertise. They demonstrate how zoos are evolving to become leaders and partners in conservation, research, and education to protect local species and natural resources.

EVALUATION OF β-HYDROXYBUTYRATE, AMINO ACIDS, AND SELECTED CHEMISTRY VALUES IN THE PLASMA OF FREE-RANGING RED-TAILED HAWKS (BUTEO JAMAICENSIS)

The red-tailed hawk (Buteo jamaicensis) is a raptor species native to North America that is commonly presented to wildlife rehabilitators and veterinarians, but little is known about biomarkers of metabolic status in this species. This study evaluates plasma β-hydroxybutyrate (BHB) and free amino acids in 24 free-ranging red-tailed hawks in good body condition in order to establish reference intervals for these values. Standard biochemical analytes were also measured. The mean plasma BHB level measured was 13.9 mg/dl. Plasma amino acids were not similar to the few available reports in avian species. Standard biochemical analytes were similar to those previously reported for red-tailed hawks. These data serve as a foundation for further investigation into the use of these biomarkers to assess metabolic status of this species in health and disease.

Differences in Mortality of Pre-Weaned and Post-Weaned Juvenile European Hedgehogs (Erinaceus europaeus) at Wildlife Rehabilitation Centres in the Czech Republic

Previous research from several European countries has indicated that the European hedgehog (Erinaceus europaeus) is in decline. Wildlife rehabilitation centres contribute toward the protection of debilitated hedgehogs, including the young. Based on data from 27 wildlife rehabilitation centres, the mortality rate and the release rate of juvenile hedgehogs were evaluated depending on whether they were from normally timed litters (admitted from April to September) or from late litters (admitted from October to March). A total of 4388 juvenile European hedgehogs were admitted to wildlife rehabilitation centres in the Czech Republic from 2011 to 2020. The number of post-weaned young from late litters admitted (28%) did not differ from the number of pre-weaned young from late litters (29%). Where the outcome was known, young from late litters had the highest mortality rate (46%) in the year of admission. The release rate was the highest in post-weaned young from normally timed litters (86%). Further research should focus on the definition of optimal care and treatment of the underlying causes for admission of juvenile hedgehogs. The reproductive strategy (the timing of litters) of European hedgehogs under the climatic conditions of the Czech Republic affects the chance of survival of young at wildlife rehabilitation centres and likely also in the wild.

Diurnal raptors at rescue centres in the Czech Republic: Reasons for admission, outcomes, and length of stay

Rescue centres play an important role in the protection of raptors living in the wild by caring for injured or debilitated animals and abandoned young with the aim of returning them to the wild. A total of 22,538 raptors were admitted to 34 rescue centres in the Czech Republic in the years 2010-2019, with an increasing trend during the monitored period (rSp = 0.7333, p < 0.05). The most frequent reasons for their admission were other injuries and fractures (26.52%), the admission of young (22.98%), and the admission of raptors injured by electric shock injuries (20.51%). It proved possible to release 42.45% of admitted raptors back into the wild, the majority of which (91.05%) were released using the hard-release method. Foster parents were used in 1% of cases and a replacement nest in 0.2% of cases involving the rearing of young. In spite of all the care provided at rescue centres, a total of 39.97% of raptors admitted either died or had to be euthanized. Among them, most raptors were euthanized or died due to injuries caused by collision with a vehicle, electric shock injuries, and other injuries. This generally occurred shortly after admission (a median of two days). The importance of the work of rescue centres lies not merely in returning injured raptors back into the wild (which proves possible in around half of all cases), but also in obtaining information about the factors endangering raptors in the wild and contributing toward a decline in their populations. The findings provide information about human-wildlife interactions in the Czech Republic and their implications for conservation as well as on the effectiveness of rescue centres to successfully treat and subsequently release raptors back into the wild.

Experimental Release of Orphaned Wild Felids into a Tropical Rainforest in Southwestern Costa Rica

Simple Summary

A male ocelot (Leopardus pardalis) and a female margay (Leopardus weidii) brought in from the wild were held in captivity and rehabilitated, then radio-collared, released, and monitored at a national wildlife refuge previously assessed for predator and prey occurrence. Subsequently, the ocelot was trapped while preying on chickens, and the margay was found dead, likely due to ocelot predation. Avoiding habituation to humans, ensuring hunting abilities, and assessing release sites likely is not sufficient to ensure successful release of these species.

Abstract

A 3- to 4-mo-old male ocelot (Leopardus pardalis) and a 6- to 8-mo-old female margay (Leopardus weidii) were brought in from the wild, held in captivity, and rehabilitated for 906 and 709 days, respectively, at the Rescate Wildlife Rescue Center in Costa Rica. During captivity, both cats were kept as isolated as possible from humans and fed appropriate live wild prey. After maturing and demonstrating the ability to capture and feed on live prey, the cats were radio-collared, released at a national wildlife refuge previously assessed for predator and prey occurrence, and monitored. After 54 days, the ocelot was trapped while preying on chickens in a nearby community, and after 20 days, the margay was found dead, likely due to ocelot predation. Avoiding habituation to humans, assuring hunting abilities, and assessing release sites likely is not sufficient to assure successful release of these species, and more experimental releases with innovative and detailed protocols and monitoring are needed.