Search

In an age of rewilding and dramatic declines in biodiversity, we are developing a new way to reintroduce raptors: parental hacking. The principle behind it is similar to traditional hacking, where the birds are released without contact with adult conspecifics. In parental hacking, our method, the parents feed their own offspring until the end of the post-fledgling dependency period. Our programme aims to reintroduce the white-tailed sea eagle (Haliaeetus albicilla) to the Upper Rhône Basin in France. It started in 2022 and will continue until 2030, with the release of 80 young eagles. We describe the method used in 2022, followed by the improvements made in 2023, and finally compare the two years. The young eagles were raised in aviaries at the reintroduction site by their captive-born parents in the Aigles du Léman Park (Haute-Savoie, France). In 2022, two young females and two young males were released as soon as they were able to fly at the age of three months, but they often ended up on the ground due to a lack of flying ability and attacks from wild black kites (Milvus migrans) defending their territory. Therefore, the young eagles were returned to their parents' aviary before being released a second time at five months in August 2022. One month after release, one male was already 50 km from the reintroduction site, while the other three stayed close to the park. In 2023, five young females and five young males were released at five months. This came after four weeks in a large training aviary to learn how to fly, perch, and fish. The behaviour of the young eagles after release varied greatly between individuals. Overall, 4 out of 10 young eagles travelled long distances and did not return to the reintroduction site to feed within a month, while the other 6 chose to stay close (within 20 km) to the reintroduction site. [ABSTRACT FROM AUTHOR]

Nomadic species are challenging to conserve, because their high mobility and irregular settlement patterns make it difficult to implement targeted conservation actions. Here, we report on the first sustained attempt to protect nests of Critically Endangered Regent Honeyeaters from predation and to release zoo-bred birds into a wild breeding event. During the 2023 breeding season, targeted culling of known nest predator species within the area of 10–12 wild breeding pairs within Capertee National Park was associated with a daily nest survival rate of 97.9%. This equated to an overall nest success rate of 48.6% and resulted in the fledging of 18 juveniles from nine nests – double the average nest success rate from 2015, 2016 and 2017 (24.1%) when Regent Honeyeaters bred in the same location. Population viability analysis indicates nest protection alone could slow the rate of population decline, but its effectiveness depends on the proportion of nests that can be located and protected each year. Fourteen zoo-bred Regent Honeyeaters were released approximately half way through the breeding event. Seven zoo-bred birds were confirmed alive 5 weeks post-release, but no zoo-bred birds released in 2023 attempted to breed in this year. Although our sample is small and prone to stochastic effects, we provide non-experimental evidence that nest predator management can play a key role in boosting recruitment of juvenile Regent Honeyeaters to the wild population. In combination with the reintroduction of zoo-bred birds and habitat restoration, nest predator management can help prevent imminent extinction of the Regent Honeyeater. [ABSTRACT FROM AUTHOR]

The overexploitation and illegal hunting of wildlife resources have become the important threats to biodiversity. The incessant practice of blending unlawfully acquired wild animals with legally farmed ones to conceal illicit activities necessitates our ability to discern between the two sources through scientific identification. Skeletal muscle serves as one of the primary targets for illegal hunting and trade products; however, an effective means of identifying their source remains elusive. In this study, we selected the common pheasant (Phasianus colchicus), a novel poultry species classified in the National Catalogue of Livestock and Poultry Genetic Resources as well as being considered as an exemplar case. We employed methylation-sensitive high resolution genetic melting（MS-HRM) assay to test 26 potential methylation level between wild and captive common pheasants at specific sites. We identified 11 loci that could be consistently detected. Statistical analysis revealed that seven sites including LOC116232884, NFATC2, FGF9-3, FGF9-2, MAPK8, DUSP10 and MYCN exhibited significant or highly significant differences in methylation levels between the two groups (P = 0. 000 - 0. 004) . The overall accuracy rate for discriminating each locus ranged from 62. 22% to 82. 78%. Furthermore, the cumulative discrimination power reached 99. 999 93%. The findings not only offer valuable locus resources and detection methods for distinguishing between wild and captive common pheasants but also serve as direct reference for identifying other similar species. [ABSTRACT FROM AUTHOR]

One of the conservation measures of the globally near-threatened cinereous vulture is restoring populations via translocations, with some vultures originating from breeding centers. These centers need to have reproductive success, and securing good welfare levels should be a priority due to the negative implications a compromised welfare has on reproduction. Thus, assessing welfare in breeding centers is essential. Remote methods should be preferred, such as behavior analysis and use of space using camera systems. The study's first objective was to develop an activity budget that could be used as a baseline for detecting behavior irregularities. The second was to determine if behavior analysis and use of space could detect potential welfare issues in a breeding center. The study developed an activity budget that could be used as a standard for behavior analysis for the captive population. Behavior irregularities were detected, and the potential need to improve the enclosure and its surroundings were noticed. Altogether, the proposed methodology and results will contribute to the detection of possible welfare issues in breeding centers and, consequently, improve reproductive success and species' conservation. [ABSTRACT FROM AUTHOR]

The endangered Sonoran pronghorn (Antilocapra americana sonoriensis) has a large portion of its range within a military operations area in southwestern Arizona, USA. Sonoran pronghorn have been actively managed in this region for more than 20 years. Recovery efforts have included release of captive‐born pronghorn into areas both currently and historically occupied by wild pronghorn. These areas provide habitat for federally endangered essential and experimental non‐essential, referred to as 10(j), pronghorn populations. More than 20 years of monitoring efforts have resulted in a large dataset on their spatial occurrence and movement within these areas. To synthesize long‐term trends and seasonality in Sonoran pronghorn movement and mortality, we employed a suite of quantitative analyses that characterized the pronghorns' 1) individual and population‐level home ranges, 2) occurrence near active military targets, 3) trends in seasonal group sizes and composition, 4) sex‐ and group‐specific survivorship, and 5) changes in movement‐based behavior following release from captivity. We found strong seasonal trends throughout, including sex‐specific differences in seasonal movement rates, home ranges, survival, and group composition. Further, captive‐born pronghorn released into the endangered population exhibited markedly higher survival compared to those released in 10(j) areas. Captive‐born pronghorn exhibited significant seasonal use of active military target areas. These analyses, which represent the most comprehensive analysis of Sonoran pronghorn movement and survival to date, have important implications for the future conservation and management of this endangered species. Our results indicate that active management of endangered Sonoran pronghorn has successfully increased survival, and we recommend maintaining or increasing current recovery efforts, such as captive breeding and placement of supplemental resources throughout their range (e.g., freestanding water and supplemental forage), to further boost the survivorship of both wild‐ and captive‐born pronghorn. Moreover, future management efforts could use our seasonality results to create dynamic prediction models of when and where pronghorn are likely to overlap with military activities to best manage interactions. Our methods have added application to other mobile species of conservation interest occurring in disturbed and resource‐limited landscapes. [ABSTRACT FROM AUTHOR]

Captive breeding of freshwater mussels is essential for conservation strategies to maintain populations of endangered bivalve mollusks. In the Czech Republic, breeders use detritus from natural sources, preferably from nearby streams and spring areas, to prepare pearl mussels for release into the target localities to reestablish sustainable populations in their native habitats. This strategy is subject to sudden changes, and breeders must consider different detritus qualities between seasons and the unpredictability of weather conditions. Therefore, harvesting natural detritus on a regular basis is challenging and time-consuming, and more samples require more testing, which increases the cost of captive breeding. We proved that juvenile freshwater pearl mussels grew faster when fed detritus stored frozen in a freezer than when fed the same chilled detritus. Therefore, detritus can be harvested under optimal conditions and stored in a freezer for the remaining season, thereby simplifying and reducing mussel conservation costs. Moreover, this approach offers a sustainable, environmentally friendly method that does not require the industrial production of artificial feeds. [ABSTRACT FROM AUTHOR]

The Alaotran gentle lemur (Hapalemur alaotrensis) is one of the world's most endangered primates and shows low success rates in captive breeding programmes. This study tested biologically relevant scent enrichment using two synthesised mixtures likely to convey information about female fertility on the behaviour of three unsuccessful breeding pairs in captivity. Specifically, we compared the baseline and enrichment periods by combining behavioural observations (n = 240 h) with faecal endocrinology (n = 80 samples), focussing on cortisol and testosterone measurements via enzyme immunoassay techniques. Then, we tested two different mixtures to assess potential behavioural differences and evaluate the effectiveness of olfactory enrichment using scented and unscented cotton strips. Olfactory behaviours differed by sex and enrichment conditions, with both sexes exhibiting increased behaviours during enrichment compared to the baseline. Sexual behaviours increased during the enrichment period, with variations in frequency between males and females depending on the condition. No significant changes were observed in faecal cortisol levels. However, one male showed a significant increase in testosterone during the second enrichment mixture. Nevertheless, overall differences between baseline and enrichment were not significant. Our findings suggest that while the scent enrichment showed limited effectiveness, biologically meaningful scents may trigger species-specific behaviours. [ABSTRACT FROM AUTHOR]

Captive breeding can be a useful tool for the management of threatened species, but such programs often begin with a bottleneck which may lower reproductive fitness by increasing inbreeding and allowing deleterious alleles to increase in frequency by reducing effective population size. Dryococelus australis, the Lord Howe Island stick insect, is a critically endangered insect that has been bred at the Melbourne Zoo in Melbourne, Australia, since shortly after the species was rediscovered in 2001. We analysed a long‐term dataset of phenotypic measurements from this captive breeding program to determine whether reproductive fitness has declined in captivity. We found a clear signal of decline in direct (egg hatching success) and indirect (egg and nymph size) fitness indicators over time. We compared a captive line descended from the original program founders to a new hybrid line that has recent wild ancestry. The hybrid line showed an immediate improvement in egg hatch rate, suggesting the potential for genetic rescue. Egg and nymph size did not show as dramatic a change, although this line had only existed for just over a single generation at the time of data collection. These results argue strongly for the regular sourcing of new genetic material from the wild D. australis population to counteract fitness declines in captivity. Aside from benefiting the captive population, this would also improve the prospects of establishing new wild populations in the future, using individuals sourced from captivity. [ABSTRACT FROM AUTHOR]

Ex situ conservation is a complementary strategy to in situ efforts and is vital for safeguarding endangered species through maintenance and breeding in captivity with potential for reintroductions into natural environments. However, it is crucial to recognize that prolonged captivity can lead to diminished abilities of organisms over generations. Factors linked to the impact of phenotypic plasticity during development, such as restricted movement, may affect organism performance during ex situ conservation efforts, potentially making reintroduction into the wild unfeasible. Consequently, it is imperative to analyze physiological differences between captive‐bred and wild individuals. Therefore, this study investigates how captivity influences locomotor performance, morphology, and metabolic capacities of adults and juveniles of the threatened treefrog Ololygon alcatraz, in comparison to natural populations. We obtained proportional measurements of individuals and assessed their locomotor performance through jumping exercise. We also measured the metabolic capacities of the frogs by examining the activity of enzymes involved in energetic metabolic pathways in their skeletal muscle fibers. We found that wild adult frogs had larger limbs, greater jumping abilities, and a more glycolytic profile, while captive adult frogs had smaller limbs and increased aerobic enzyme activity compared to their wild counterparts. These differences probably arise from phenotypic plasticity in ontogenetic development that differs between captive and natural environments, as juveniles do not show such differences. These results highlight the need for innovative strategies in managing captive O. alcatraz populations, which will aid in their successful translocation to the wild and strengthen ex situ conservation efforts. [ABSTRACT FROM AUTHOR]

This study presented the first comprehensive report on the induced breeding and embryonic development of Mystus tengara. Matured brooders were induced with synthetic hormone (GONOPRO-FH) at a dosage of 0.5ml/ kg body weight for males and 1ml/ kg body weight for females in each trial. The trial conducted at a water temperature of 29°C yielded the highest fertilization rate of 84% and hatching rate of 93% among the three trials. The fertilized eggs were 0.5mm in diameter, spherical, transparent, and highly adhesive. The zygote stage extended up to 00:15 hour post fertilization (hpf), followed by cleavage stage (00:15-01:20 hpf), blastula stage (01:40-03:25 hpf), gastrula stage (03:45-05:24 hpf), segmentation stage (08:20-12:27 hpf) and pharyngula stage (13:09-14:10 hpf). Hatching occurs at 15:00 hpf, resulting in larvae with an average length of 1.62mm. The outcomes of this study hold significant implications for commercial fish farmers and breeders, facilitating the production of superior-quality seeds at reduced expenses. Furthermore, these findings contribute to both species' conservation efforts and advancements in species taxonomy. [ABSTRACT FROM AUTHOR]

Conservation breeding programs (CBPs) are often the lifeline between extinction and survival for many imperilled amphibian species. With the goal of recovering wild populations, CBP success is reliant on their ability to successfully manage ex situ populations over time, breed viable offspring, and maintain genetic diversity and adaptive potential. Reproductive technologies have emerged as an important tool in the conservation toolkit to allow managers to improve reproductive output and genetic management, and their use in amphibian conservation is expanding. To date, studies investigating the efficacy of hormone therapies in amphibians typically only report spawning and fertility rates and do not monitor offspring to later stages of development. For the first time, here we assess the effect of hormone therapies on captive breeding outcomes beyond oviposition, to the point of metamorphosis, in the critically endangered Baw Baw frog, Philoria frosti. To determine the effect of hormone therapy on spawning success and offspring viability, male-female pairs were administered either 0 µg/g gonadotropin-releasing hormone agonist (GnRHa), 0.5 µg/g GnRHa, or 0.5 µg/g GnRHa + 10 µg/g metoclopramide (MET) (n = 12 pairs/treatment), and the number of pairs ovipositing, time to oviposition, clutch size, metamorph mass, and the proportion and number (mean and total) of offspring to metamorphosis were quantified. Overall, the percentage of pairs that oviposited was high across all treatment groups (92-100%). The percentage of fertile clutches was highest in the GnRHa group (92%) and lowest in the GnRHa + MET group (82%), though differences were not statistically significant. Both hormone treatment groups took significantly less time to oviposit than the control pairs. Notably, the proportion of eggs developing to metamorphosis was significantly higher in the GnRHa group, resulting in 74% (total eggs=539) metamorphosing compared to approximately 50% in the control and GnRHa +MET treatments (total eggs= 273 and 264, respectively). Interestingly, weight at metamorphosis was statistically similar across all groups, and results are consistent with previous studies in this species that show a narrow range in size at metamorphosis. The continued application of GnRHa is recommended to improve conservation outcomes for the critically endangered Baw Baw frog. The outcomes of this research advance our understanding of the impact of hormone therapies on reproductive outcomes and will inform amphibian conservation breeding programs globally. [ABSTRACT FROM AUTHOR]

Reintroductions of threatened species is a conservation strategy utilised around the world. Unfortunately, many translocated individuals have poor rates of survival post‐release. If released individuals are unable to socially integrate into wild populations, they might lose the safety of the group or fail to learn critical skills. We examined the effects of age and captivity on sociality and migration survival for the critically endangered orange‐bellied parrot (Neophema chrysogaster). As part of recovery efforts, adult birds are released in spring to contribute to breeding and juveniles are released in autumn prior to migration. Historically, captive‐bred adults have low rates of migration survival, whereas captive and wild juveniles survive at comparable rates. We investigated both the long‐term impacts of captivity on sociality and how sociality impacted migration survival by constructing social networks and comparing captive and wild birds of different age classes. We found no differences between captive and wild birds, suggesting that released birds integrated into the population. However, juveniles were more strongly connected and demonstrated greater network stability than adults. While we found no impact of sociality on survival, our results provide evidence of different migration strategies previously described for juveniles and adults: adults depart in small groups and juveniles depart as a larger flock a few weeks later. We suggest that the low migration survival of captive‐bred adults may be attributable to this cohort missing the juvenile flocking phase. These results suggest that a juvenile developmental phase may be impactful in this species for future survival. [ABSTRACT FROM AUTHOR]

Simple Summary: This study presents an integrated conservation framework for the globally threatened fishing cat, synthesizing both ex situ management and in situ strategies. The strategy aligns with the One Plan Approach, which views captive populations as part of a broader metapopulation network, and the Opportunities to Thrive framework, which emphasizes animal welfare in captivity. This study analyzed the genetic diversity of a recently initiated fishing cat captive breeding population by the West Bengal Zoo Authority, India, and conducted a population viability analysis. The results suggest that the current genetic diversity (56%) and population carrying capacity (30 individuals) can be sustained for over 100 years through a strategy of supplementation and harvesting. Introducing two adult males and females annually will allow for sustainable harvesting to supplement wild populations. Additionally, this study identified 21 potential reintroduction zones in the Sundarbans and Terai regions of West Bengal, using environmental criteria that favor fishing cat occurrence. This work offers a comprehensive blueprint for applying the One Plan Approach to ensure the long-term survival of the fishing cat. The One Plan Approach advocates for a hybrid species management framework, wherein captive-bred populations are considered metapopulations nested within a broader network of zoos and wild populations Additionally, the Opportunities to Thrive framework aims to enhance animal welfare by addressing the physiological, psychological, and emotional needs of captive individuals, thereby improving conservation outcomes. Here, we present an integrated framework for the conservation of a globally threatened wetland wild cat species, the fishing cat, by synthesizing optimal ex situ management practices and in situ conservation strategies. Further, we examined the genetic constitution of the founder population in a fishing cat captive breeding program that was recently initiated by the West Bengal Zoo Authority, India and conducted a population viability analysis to suggest how best to maintain the genetic diversity of the population. We found that the present genetic diversity of 56% and maximum carrying capacity of the captive population (30 individuals) can be maintained for more than 100 years with a combination of supplementation and harvesting. Keeping stochastic events in mind, the introduction of two adult males and females to the existing population each year will seamlessly allow the harvesting of two adult males and two adult females every alternate year to supplement wild populations. Further, we adopted the proposed integrated framework to delineate recommendations for the supplementation of wild populations in West Bengal. We used environmental criteria known to influence fishing cat occurrence to identify 21 potential reintroduction zones in the Sundarbans landscape and Terai region in northern West Bengal with habitable areas for the fishing cat that are larger than the maximum known species' home range. Our study is timely and insightful because it provides a holistic blueprint for implementing the One Plan Approach in safeguarding a threatened species. [ABSTRACT FROM AUTHOR]

ABSTRACT Translocating individuals from multiple source populations is one way to bolster genetic variation and avoid inbreeding in newly established populations. However, mixing isolated populations, especially from islands, can potentially lead to outbreeding depression and/or assortative mating, which may limit interbreeding between source populations. Here, we investigated genetic consequences of mixing individuals from two island populations of the dibbler (Parantechinus apicalis) in an island translocation. Despite a high level of genetic divergence between the source populations (FST ranges 0.33–0.64), and significant differences in body size, individuals with different ancestries were able to successfully interbreed in captivity and in the wild. However, the genetic contributions from each source population were unequal initially despite each of the source populations contributing an equal number of founders. Mating success of captive animals based on the pedigree suggests that this bias toward one source population was due to founder mortality and the mating success of younger and heavier animals. Nevertheless, genetic contributions in the translocated population became equal over time with no parental purebreds, suggesting an extreme excess of hybrids across multiple years. While genetic variation in the translocated population was comparable or higher than the source populations, the increase was short‐lived. Genetic composition of captive animals may not reflect what happens in the wild. These changes post‐translocation highlight the need for continued genetic monitoring.

Rearing animals in captivity for conservation translocation is a complex undertaking that demands interdisciplinary management tactics. The maladapted behaviors that captive animals can develop create unique problems for wildlife managers seeking to release these animals into the wild. Often, released captive animals show decreased survival due to predation and their inability to display appropriate anti-predator, vigilance, and risk-analysis behaviors. Additionally, released animals may have poor foraging skills, further increasing their vulnerability to predation. Often conservation translocation programs use anti-predator training to ameliorate these maladapted behaviors before release but find mixed results in behavioral responses. The behavioral scope of analyzing the effect of anti-predator trainings is frequently narrow; the effect of this training on an animal's risk-analysis competency, or ability to assess the predation risk of a foraging patch and subsequently adjust its behavior, remains unstudied. Using a captive-reared passerine species, the American robin (Turdus migratorius) (46 individuals), we applied an experimental giving up density test (GUD) to analyze the effect of anti-predator training on the robins' vigilance/risk-analysis behaviors, patch choice, and the GUD of food left behind after one foraging session. Robins moved and foraged freely between 3 foraging patches of differing predation risk before and after a hawk silhouette was presented for 1 min. Results indicate that after anti-predator training, robins displayed increased vigilance across most foraging patches and better foraging efficiency (higher vigilance and latency to forage with simultaneous lower GUD) in the safest patch. These results can have positive survival implications post-release, however, more research on this training is needed because anti-predator training has the potential to elicit indiscriminate increased vigilance to the detriment of foraging gains. Further research is required to standardize GUD's application in translocation programs with multigenerational captive-bred animals to fully comprehend its effectiveness in identifying and correcting maladaptive behaviors. GUD tests combined with behavioral analysis should be used by conservation translocation managers to examine the need for anti-predator and foraging trainings, the effects of trainings, and a group's suitability for release. [ABSTRACT FROM AUTHOR]

Dystocia, or obstructed labor, is a well‐documented phenomenon in various captive vertebrates, including fish. However, despite the documentation of dystocia in several viviparous (live‐bearing) Chondrichthyan species (i.e., sharks, rays, skates, and chimaeras), there are no reports to date of dystocia in any oviparous (egg‐laying) species. Here we present a case of a captive female epaulette shark (Hemiscyllium ocellatum) that demonstrated symptoms of dystocia in a research‐related captive breeding programme. This communication serves as documentation that dystocia can occur in oviparous Chondrichthyans, and this information can help inform researchers and veterinary practitioners for improved care. [ABSTRACT FROM AUTHOR]

Leadbeater's possums (Gymnobelideus leadbeateri) are a critically endangered marsupial found in a restricted area of cold, wet forest in South‐Eastern Australia. The majority of Leadbeater's possums inhabit highland forest, with one outlying lowland population. In 2012, a breeding program was established for the lowland Leadbeater's possums when this genetically distinct population faced imminent extinction. Successful reproduction by highland Leadbeater's possums in the international zoo‐based population between 1970 and 2010 led to the widespread belief that the species bred readily in captivity. Lowland possums have not bred in the 2012–2021 contemporary captive conservation breeding program. This study reviewed the historic captive‐breeding data and found that of the 84% (162/194) that reached reproductive maturity; 37% of males (n = 30) and 39.5% of females (n = 32) bred, and this success was highly skewed towards a subset of highly fecund individuals (14% of females and 15% of males produced 75% and 80% of all offspring). Although lack of reproductive output in the captive lowland animals could be explained if age at mortality was lower than that of highlands possums, comparison of the longevity of highland and lowland animals had no significant difference. Conservation objectives that specify how captive breeding may support in situ recovery of wild populations are integral to the success of captive programs. A lack of reflective analysis of past husbandry records allowed misconceptions of success and approaches implemented in the management of the breeding program, reducing the benefits for the conservation of this high profile threatened species. This case study provides a lesson for the management of conservation breeding programs and illustrates the importance of well‐defined conservation objectives, integration of in situ and ex situ strategies, and the importance of objective, systematic and timely analysis of available evidence to inform management objectives and improve conservation outcomes in real time. [ABSTRACT FROM AUTHOR]

Captive‐breeding programs are increasingly implemented to curb population declines but can have unintended negative effects on genetic diversity and phenotypes. Through an analysis of ~10 years of genetic monitoring, pedigree information, and phenotypic data, we evaluated a captive‐breeding program that uses adaptive management to reduce inbreeding and improve captive broodstock performance. A captive‐breeding program was established in 2012 to reintroduce spring‐run Chinook salmon to the southern edge of their range in California's San Joaquin River (SJR), using fish produced each year at the nearby Feather River Hatchery (FRH). We found that the SJR program adequately captured the genetic diversity of the FRH source population and that mate pairings guided by genetic relatedness reduced inbreeding. However, the SJR broodstock reared in captivity had smaller body size at maturity in comparison to the FRH source broodstock which matures at sea, but this effect disappeared when SJR juveniles were released from captivity to mature at sea. Phenotypic traits of SJR female parents also influenced reproductive performance; older mothers and those with smaller eggs had offspring with lower survival. These findings demonstrate that adaptive genetic monitoring and pedigree information can be powerful tools for reducing risks of captive breeding and evaluating program effectiveness. [ABSTRACT FROM AUTHOR]

The success of avian translocations depends on many factors. Release age is often cited as an influential factor that warrants further study, yet no general guidelines exist to improve the outcome of translocations. We conducted a systematic review of literature on captive‐reared or wild‐caught birds that incorporated >1 age class in their analyses of post‐release survival, dispersal, or reproduction. Fifty‐two studies met our search criteria, and 39 were retained for an evaluation of post‐release survival. For studies reporting at least one trend, more reported higher post‐release survival when birds were translocated at younger ages (68%) than at older ages (32%). This pattern was most pronounced for wild‐caught birds and for captive‐reared birds released within their first year of life. Captive‐reared birds of prey were an exception, with birds released at older ages often having higher survival than birds released at younger ages. We review the authors' hypotheses for why birds released at younger ages are more likely to settle, survive, and breed. More research is needed on the potential effects of release age on dispersal and reproduction. We recommend that future studies incorporate age of release as a covariate and control for the effect of season of release in experiments. [ABSTRACT FROM AUTHOR]

The golden-backed tree-rat (Mesembriomys macrurus) is a large semi-arboreal rodent that has suffered a significant reduction in range since European settlement. Seven (three male, four female) founding adults for a captive colony were captured on the Mitchell Plateau, Western Australia, and transferred to Alice Springs, Northern Territory. The reproduction, growth, development and behaviour of M. macrurus in captivity were recorded. Twenty-three litters were born with litter size of 1–3 (median litter size: 2; overall sex ratio parity). There was no apparent seasonality in breeding. Oestrous cycle (9.9 ± 0.4 days) and gestation (46.8 ± 2.8 days) were estimated from known births and birth dates determined from calculated growth curves. Mean weight at birth was 17.2 g (±1.3, n = 12) and growth of the young was rapid, with head length reaching the asymptote from 54 days and head-body length from 83 days. Young were weaned at about 40 days and adult pelage complete by 98 days. Reproductive maturity occurred from 5 to 6 months for females and in males testes became scrotal from 76 days. Developmental stages and captive behaviour were also recorded. These results are compared with reproduction and growth of the closely related black-footed tree-rat (M. gouldii) and brush-tailed rabbit-rat (Conilurus penicillatus). The golden-backed tree-rat, a large native rodent from tropical Western Australia and Northern Territory, was once abundant and widespread, but numbers have declined greatly. Its conservation depends on knowing its ecology and breeding biology, and in this study we provide the first details of the breeding biology of this tree-rat. This information is essential for developing conservation strategies to ensure the survival of this unique Australian species. Photograph by Euan Ritchie. [ABSTRACT FROM AUTHOR]

Boreal chorus frogs (Pseudacris maculata Agassiz 1850) are a widespread amphibian in North America, but several populations are in decline. Specifically, we are developing captive breeding and reintroduction methods for the Great Lakes/St. Lawrence–Canadian Shield population. Here we present the effects of tadpole density, food variety, and addition of supplemental minerals to rearing water on the growth, development, and survival during the larval and metamorph/juvenile stages. We conducted two experiments using a factorial design. We found that low tadpole density (1 vs. 2 tadpoles/L) and high food variety (five food items vs. three food items) significantly increased tadpole body length and Gosner stage after 2 weeks (p <.001), increased survival to metamorphosis (p <.001), decreased time to metamorphosis (p <.001), and increased weight after metamorphosis (p <.001). On average, tadpoles in the high density/low food treatment, compared to the low density/high food, were 25% smaller after 2 weeks, had 3.9× lower survival to metamorphosis, took 1.25× longer to reach metamorphosis, and weighed 1.5× less after metamorphosis. In contrast, neither density (0.5 vs. 1 tadpole/L) nor mineral supplemented water affected growth and development, but tadpole survival was higher at 1 tadpole/L. Our findings demonstrate the feasibility of rearing boreal chorus frogs in captivity and provide guidelines for rearing this and similar species in a laboratory environment. [ABSTRACT FROM AUTHOR]

Fruit bats (genus Pteropus) are typically island‐endemic species important in seed dispersal and reforestation that are vulnerable to increased extinction risk. An effective method of reducing extinction risk in vulnerable species that cannot be conserved in their native habitat is establishing an ex‐situ captive breeding programme. Due to anthropogenic threats and low population numbers, in the early 1990s, a captive breeding programme was established at Jersey Zoo, British Isles, for Critically Endangered Livingstone's fruit bats (Pteropus livingstonii). Here we use six polymorphic microsatellite loci to assess genetic diversity in the captive breeding population of Livingstone's fruit bats (P. livingstonii), 30 years after the programme's establishment, investigating change over generations and comparing our findings with published data from the wild population. We found no significant difference between the genetic diversity in the captive and wild populations of Livingstone's fruit bats (P. livingstonii), in both expected heterozygosity and allelic richness. The captive population has retained a comparable level of genetic diversity to that documented in the wild, and there has been no significant decline in genetic diversity over the last 30 years. We advise that a full pedigree of the paternal lineage is created to improve the management of the captive breeding programme and further reduce the possibility of inbreeding. However, it appears that the captive breeding programme is currently effective at maintaining genetic diversity at levels comparable to those seen in the wild population, which suggests reintroductions could be viable if genetic diversity remains stable in captivity. Research highlights: The captive breeding programme of Critically Endangered Livingstone's fruit bats shows comparable genetic diversity to current wild populations.This level of genetic diversity has remained stable in the captive population for 30 years, since its first establishment, across four generations of animals.The captive breeding programme of Livingstone's fruit bats is currently managed effectively, minimising inbreeding, and retains reintroduction potential. [ABSTRACT FROM AUTHOR]

Translocation of captive-bred animals is a widely used conservation strategy to support the recovery of imperiled wild populations. Identifying which factors enhance or limit survival after release can be important in adapting translocation strategies, particularly for species with low survival rates after release from captivity. Many translocation programs track post-translocation survival, but few complete spatial-statistical assessments of mortality risk associated with release environments. Typically, few animals are released from captive breeding programs, limiting the sample size available for analyses. We aimed to create a workflow that used limited datasets to evaluate the influence of spatial conditions and other factors on mortality risk. Greater sage-grouse (Centrocercus urophasianus) are endangered in Canada and of conservation concern throughout their range in the United States. After the species declined precipitously in Canada, a captive breeding program was initiated with subsequent releases in Alberta and Saskatchewan. Despite success in captive breeding, mortality rates of released sage-grouse were high. We used GPS- and VHF-based locations of released sage-grouse to determine how spatial features influence mortality risk of sage-grouse after release from captivity. We implemented a multistep approach to quantify and map risk relative to the environmental features associated with mortality. We also assessed whether the movement behaviors of sage-grouse correspond with environmental risk factors by using a combination of survival models and integrated step-selection functions. Mortality of sage-grouse in Alberta was hastened in areas close to anthropogenic disturbance. Although birds in Alberta avoided areas of higher mortality risk, those in Saskatchewan did not, perhaps due to environmental and selection constraints. This multistep approach allowed us to utilize small sample sizes to assess key risk factors in the landscape. This process supports the adaptive modification of translocation plans and can similarly support other data-limited scientists and managers in assessing environmental mortality risk and defining conservation actions for endangered species. [ABSTRACT FROM AUTHOR]

In recent decades, studies on animal coloration have expanded significantly, from understanding color production and perception mechanisms to exploring the selective pressures driving these patterns. Conservation biology has begun leveraging these studies to develop effective strategies, gauge public support for conservation projects, select flagship species, and determine reproductive pairs and optimal rearing and release conditions for captive breeding. Critically endangered Aeolian wall lizards (Podarcis raffonei) were housed at the Fondazione Bioparco di Roma for a pilot captive breeding project following alarming hypotheses of rising numbers of "green" hybrids (P. raffonei × P. siculus) in one of the four surviving populations. Through a quantitative analysis of visible dorsal color in captive and natural populations, we aim to determine whether P. raffonei is characterized by seasonal variation in its dorsal coloration and if color is influenced by sex and ontogenesis. Our findings show that P. raffonei's dorsal pigmentation varies between seasons. In spring, the size and age of the animals does not seem to affect any color component, while the sexes always differ in their hue, with males having consistently more yellow-green dorsa. Between-year analyses, including measurements from the wild population, indicate that yearly variation is not limited to the captive population but also occurs in nature. We caution against identifying potential hybrids based solely on phenotypic traits. [ABSTRACT FROM AUTHOR]

After a massive decline, the Griffon Vulture (Gyps fulvus) population in Bulgaria has now stabilised as a result of the hard work of conservation programmes, although it is still listed as an Endangered species (EN) in the country's Red Data Book. Due to a series of unfortunate events, another species - the Cinereous Vulture (Aegypius monachus) became extinct in Bulgaria and recovered only recently due to systematic re-introduction efforts. Along with the poor living conditions, a predisposing factor for the decreasing population of the vultures is the fact they hatch only a single egg; two may be laid on exceptions. The survival rate of the young is from medium to low. In that order, a method of double clutching has been applied in the hope of preserving and retrieving both of the vultures. This article aims to introduce the double clutching method in detail, as well as to show the results of its implementation into the breeding programme of the Cinereous Vulture and the Griffon Vulture at the Wildlife Rehabilitation and Breeding Centre of Green Balkans – Stara Zagora NGO. This research studies the time period 2019-2023. The purpose of this study is to compare the results of natural copulation and hatching and those of the double clutching method. The data taken are used for studies for both the Cinereous and the Griffon Vulture's reproduction in correlation with their feeding programme and living conditions. The results of the study will be summarised into the following text for the purposes of shedding light on the positives of the double clutching method. [ABSTRACT FROM AUTHOR]

Captive breeding of wild animals is one of the mainstream measures for international wildlife conservation at present, but its actual conservation impact on wild populations is not clear. The viewpoints and attitudes of experts and scholars can help to clarify the protective role of captive breeding, and sentiment analysis is an important tool to judge individual attitudes and viewpoints. Based on the sentiment lexicon method, this study conducts a sentiment analysis on the literature abstracts related to the impact of international wildlife captive breeding and conservation. We searched the Web of Science database (1900—2022) for 81 articles on conservation impacts or effects of wildlife captive breeding and vertebrates. The literature analysis indicated that at present, the research on the impact of captive breeding of wildlife is continuing to deepen, and the species studied are mainly mammals. The proportion scholars’ attitudes towards the impact of captive breeding and protection was positive emptions (56. 8%), negative emotions (37. 0%), and neutral emotions (6. 2%) . The emotional attitudes of scholars were significantly related to breeding species. Red-billed chough (Pyrrhocorax pyrrhocorax), primates, ungulates and carnivora were representative species with positive attitudes, while the Asian houbara (Chlamydotis macqueenii), pangolins (Manis spp.), tigers (Panthera tigris) and aquatic mammals were representative species with negative attitudes. The success of captive breeding of representative species may be related to adaptability of human intervention and breeding technology maturity. The positive emotions of scholars on breeding of ex situ conservation population were relatively higher (63. 6%), while the negative emotions on management and utilization population breeding were higher (60. 0%) . Based on the above analysis, it is concluded that captive breeding is still one of the effective means for wild animal conservation, and both breeding of ex situ conservation population and breeding of management and utilization population can play a positive role under certain conditions. [ABSTRACT FROM AUTHOR]

This article discusses the decline of parasitic freshwater mussel populations and the need for conservation methods, particularly captive breeding, to reintroduce and protect these species. The focus is on the Depressed River Mussel (Pseudanodonta complanata), which is classified as vulnerable. The article presents a novel method for the long-term housing and husbandry of P. complanata, inspired by an outdoor mesocosm system used in Virginia, USA. The method involves creating a lake-like ecosystem with natural food sources for the mussels, reducing the reliance on nutrient-rich water or expensive custom food mixtures. The article also highlights the successful reproduction of P. complanata in captivity using this method and suggests further research to test its scalability and potential for juvenile mussel production. [Extracted from the article]

Human-induced global change poses an increasingly severe threat to biodiversity, with species having limited population sizes being particularly vulnerable. Mapping and modeling the distribution ranges of such species, along with detecting potential range shifts and contractions at both local and regional scales, are essential for developing effective conservation plans. Ruppell's vulture Gyps rueppelli, an ecologically important bird species native to Africa, is experiencing a rapid decline in its range. The purpose of this study is to map and model potential regional spatio-temporal distribution of Ruppell's vulture in Africa, alongside detecting the possibility of the species' range shifts and contractions. A total of 804 rarefied localities were identified where the Ruppell's vulture was the dominant bird species. This study employed the Maximum Entropy (MaxEnt) algorithm to perform species distribution modeling for the Ruppell's vulture. The modeling considered current climate conditions (1970s-2000s) as a baseline, along with two future climate change scenarios (Shared Socioeconomic Pathways: SSPs 245 and 585) for two future time periods (2050s and 2070s). The model's performance was evaluated by optimizing settings and examining the Area under the Receiver Operating Characteristic Curve (AUC-ROC). Among the 13 bioclimatic and anthropogenic variables included in the model, four (isothermality, cropland expansion, anthropogenic biomes, and urban expansion (in order of importance)) emerged as the most influential drivers of Ruppell's vulture regional distribution. All considered Species distribution models (SDMs) achieved high predictive performance, with AUC-ROC values exceeding 0.9.The model predicted a total of approximately 19,453 ha of suitable habitat for Ruppell's vultures in Africa, with East Africa identified as the most prominent region under the current climate scenario. Isothermality (38.8%) was the primary factor influencing Ruppell's vulture distribution, followed by agricultural expansion (29.9%) and anthropogenic biomes (7.2%) in the face of global change. The results reveal considerable future habitat loss (up to 61%) for Ruppell's vultures in the study area, alongside an eastward range shift (longitudinal axis) by the 2050s under projected climate change scenarios. These imply that Ruppell's vultures face imminent population decline and range shift due to significant habitat loss and climate change. Hence, prioritizing the development and implementation of a coordinated conservation program that incorporates captive breeding and assisted migration is critical to save this vulture species in its native African range.

The artificial reproduction of endangered marine species populations is becoming increasingly crucial. Determining the potential for reintegration into their natural ecological niche remains a persistent obstacle in conservation biology. Spotted seals (Phoca largha) are a flagship species in the Chinese marine ecosystem. Efforts have been made to artificially breed them to prevent local extinction. Our study monitored 18 captive-born (nine) and rehabilitated (nine) individuals released into the Bohai Sea between 2010 and 2020. We examined the ecological niche-seeking behavior of captive-born seals (CS) using rehabilitated wild seals (RS) as benchmarks. It encompassed three oceanic gradients, habitat patterns, and potential threats. The findings demonstrated that CS did not return to the appropriate latitudes, horizontals, and sea surface salinity gradients in the ocean. Despite a larger potential habitat area for CS, it exhibited high temporal variability (with an average monthly fluctuation of 53 %) and demonstrated limited spatial overlap with the RS habitat (27 % overlap in July), and four indices, including the Splitting and Global Moran's Indices indicated a higher level of habitat fragmentation. Additionally, the number of shipping hotspots and collision risk within the CS habitats were twice those of the RS. These findings suggest that the released CS did not fully integrate into its native ecological niche. Our objective is to offer a pragmatic approach and framework for monitoring and assessing marine species released into the ocean.

Conservation breeding programs (CBPs) are often the lifeline between extinction and survival for many imperilled amphibian species. With the goal of recovering wild populations, CBP success is reliant on their ability to successfully manage ex situ populations over time, breed viable offspring, and maintain genetic diversity and adaptive potential. Reproductive technologies have emerged as an important tool in the conservation toolkit to allow managers to improve reproductive output and genetic management, and their use in amphibian conservation is expanding. To date, studies investigating the efficacy of hormone therapies in amphibians typically only report spawning and fertility rates and do not monitor offspring to later stages of development. For the first time, here we assess the effect of hormone therapies on captive breeding outcomes beyond oviposition, to the point of metamorphosis, in the critically endangered Baw Baw frog, Philoria frosti. To determine the effect of hormone therapy on spawning success and offspring viability, male-female pairs were administered either 0 µg/g gonadotropin-releasing hormone agonist (GnRHa), 0.5 µg/g GnRHa, or 0.5 µg/g GnRHa + 10 µg/g metoclopramide (MET) (n = 12 pairs/treatment), and the number of pairs ovipositing, time to oviposition, clutch size, metamorph mass, and the proportion and number (mean and total) of offspring to metamorphosis were quantified. Overall, the percentage of pairs that oviposited was high across all treatment groups (92-100%). The percentage of fertile clutches was highest in the GnRHa group (92%) and lowest in the GnRHa + MET group (82%), though differences were not statistically significant. Both hormone treatment groups took significantly less time to oviposit than the control pairs. Notably, the proportion of eggs developing to metamorphosis was significantly higher in the GnRHa group, resulting in 74% (total eggs=539) metamorphosing compared to approximately 50% in the control and GnRHa+MET treatments (total eggs= 273 and 264, respectively). Interestingly, weight at metamorphosis was statistically similar across all groups, and results are consistent with previous studies in this species that show a narrow range in size at metamorphosis. The continued application of GnRHa is recommended to improve conservation outcomes for the critically endangered Baw Baw frog. The outcomes of this research advance our understanding of the impact of hormone therapies on reproductive outcomes and will inform amphibian conservation breeding programs globally.

Abstract Demand for wildlife and their products continues to grow, often despite increasingly militarised regulation and consumer awareness campaigns. We review the sustainability, legality and feasibility of wildlife farming of animals, as a potential conservation tool to ensure the development of an equitable and sustainable trade model. While there are some positive examples of well‐managed wildlife farming in trade, we identify common themes of misuse including the intentional mislabelling of wild‐caught specimens in global trade and the use of wild‐caught individuals to supplement captive stocks. We also highlight the frequent failure to incorporate biological data into management strategies, resulting in the widespread use of species with potentially unfavourable life history traits, which constrain the economic and biological sustainability of wildlife farming programmes. We develop a structured decision framework to aid the examination of when wildlife farming may most benefit or hinder species conservation. Synthesis and applications. Key opportunities include developing species suitability assessments and removing barriers to legitimate participation with wildlife farming among poor, rural communities. In the absence of management strategies that address the issues of species suitability and accessibility, wildlife farming will continue to place significant strain on wild populations while failing to provide conservation value and sustainable economic returns. Read the free Plain Language Summary for this article on the Journal blog.

Rapid biodiversity loss threatens many species with extinction. Captive populations of species of conservation concern (such as those housed in zoos and dedicated breeding centres) act as an insurance should wild populations go extinct or need supplemental individuals to boost populations. Limited resources mean that captive populations are almost always small and started from few founding individuals. As a result, captive populations require careful management to minimize negative genetic impacts, with decisions about which individuals to breed together often guided by the principle of minimizing relatedness. Typically this strategy aims to retain 90% of genetic diversity over 200 years (Soulé et al., Zoo Biology, 1986, 5, 101), but it has a weakness in that it does not directly manage for genetic load. In this issue of Molecular Ecology Resources, Speak et al. (Molecular Ecology Resources, 2024, e13967) present a novel proof‐of‐concept study for taking this next step and incorporating estimates of individual genetic load into the planning of captive breeding, using an approach that is likely to be widely applicable to many captive populations. [ABSTRACT FROM AUTHOR]

Concerns about species extinctions have produced efforts to stabilize these losses and to do so on a planetary scale. These conservation efforts call upon the language and politics of the commons, although in often divergent ways. Using ethnographic research that examines efforts to save the California condor, I analyze the moral claims that animate these conservation practices. The specter of the Sixth Extinction has led conservation communities to treat the Earth as a 'planetary commons', albeit an apocalyptic one. Yet 'touching extinction' produces practices of bioethical care that exist and resist the abstractions of the planetary commons. Lastly, I offer an example of condor reintroduction into the Grand Canyon to illustrate how these commoning practices have the potential to enact 'uncommon worlds'. [ABSTRACT FROM AUTHOR]

Purpose: Aplocheilus dayi (Ceylon Killifish) is a freshwater fish endemic to Sri Lanka, but its conservation has not received much attention as uncontrolled fishing for ornamental purposes and many other human activities have posed significant threats to its survival. Therefore, this study aimed to provide baseline information on the development of a captive breeding system and to study the embryonic and larval development of A. dayi. Research Method: Matured A. dayi fish were acclimatised for two weeks prior to the experiments. A suitable breeding substrate to facilitate successful spawning was identified using two substrates; spawning mop, and sand while no substrate was used as the control. The subsequent breeding experiment (to find the best sex ratio) was performed using different sex combinations (Male: female 1:1, 1:2, 1:3, and 2:4). Subsequently, eggs were collected and analysed for fertility, hatchability, and embryonic development studies. Findings: Spawning mop seemed to be the most preferred spawning substrate for A. dayi. Egg parameters, including fertilisation rate and hatchability, were not significant upon the sex ratios; however, the ratio between male: and female (1:2) had the highest significance (p<0.05) in egg production (4 eggs/day). Moreover, we found that A. dayi eggs showed a lengthy incubation period (11 - 13 days at 25±1 °C), indicating their dormancy nature to bypass the hostile conditions before being hatched. Research Limitations: The breeding pattern under captivity needs to be examined over an extended period in different experimental settings, such as using other culture techniques with varying density ratios. Originality/Value: A. dayi can be successfully bred in captivity, and further this study gives the readers factual information on the embryonic development of A. dayi. [ABSTRACT FROM AUTHOR]

The application of reproductive technologies to amphibian conservation breeding programs is gaining momentum and the field is poised to contribute significantly toward amphibian species recovery. We briefly discuss the opportunities for reproductive technologies to enhance conservation breeding outcomes, including their potential to enhance the genetic management, and in turn, the fitness of threatened species. Despite this potential, an important consideration that is not yet well understood is the degree to which specific reproductive technologies might influence (either enhance, or in some instances potentially decrease) individual fitness and lead to shifts in population viability. The development of a standardised approach to monitoring offspring throughout life-stages to detect changes to morphology, behaviour, physiology, survivorship, and developmental trajectories is essential. The primary focus of this review is to provide a 'best-practise' framework for quantifying key fitness determining traits expected to contribute to the fitness of individuals and long-term viability of populations, which will ultimately allow us to progress the field of amphibian reproductive technologies and assess the impact of protocol refinement. [ABSTRACT FROM AUTHOR]

Once rodents have been successfully eradicated from Lord Howe Island, Australia, the critically endangered Lord Howe Island stick insect (Dryococelus australis (Montrouzier)) may be reintroduced, a century after it was thought to have become extinct. In captive populations of D. australis, elevated mortalities have been associated with bacterial pathogens. To better define the infectious risk posed by entomopathogens to the reintroduction program, we investigated the bacteria isolated from captive D. australis kept at Melbourne Zoo and on Lord Howe Island and from environmental samples and free-living invertebrates collected on various parts of the island. At Melbourne Zoo, Serratia and Pseudomonas spp. were the bacteria most frequently isolated between 2013 and 2019. Serratia spp. were also the organisms most frequently isolated from insects sampled in April 2019 from the captive population on Lord Howe Island. In addition, Serratia spp. were isolated from a range of environmental samples collected on Lord Howe Island during March–April 2019. These environmental isolates had a broader range of biochemical and molecular characteristics than those obtained from the captive insect populations. A large proportion of these isolates were urease positive and had biochemical profiles previously not described for Serratia spp. This study highlights the need for better surveillance for potential pathogens in understudied regions and sites. We conclude that infections caused by Serratia spp. might pose a problem to the captive breeding program for D. australis but that the risk of introducing novel pathogens to Lord Howe Island through infected insects is low. Our study explores some of the potential risks involved in captive breeding and provides a valuable example of using pathogen surveillance to better inform an invertebrate conservation program. [ABSTRACT FROM AUTHOR]

The Jardine River turtle (Emydura subglobosa) was selected as a potential model species for studies on freshwater turtles and general reptile physiology. Attempts to establish a freshwater turtle laboratory line were made when an adult pair of E. subglobosa was received in 2016 by the Laboratory of Inland Fisheries and Aquaculture (Poznań University of Life Sciences). The first generation of offspring was obtained in 2017, and the second generation in 2023. In each generation, unrelated specimens were added to the animal cohort to avoid inbreeding. Husbandry regimes were established, and a basal diet for nutritional experiments was developed and manufactured by two methods, producing extruded feed and a gelatinesolidified variant. The establishment of the Freshwater Turtle Laboratory Line (FTLL) provides an opportunity to improve the development of husbandry techniques, increase knowledge of reptile physiology, and use laboratory-raised animals as model species for research and education. [ABSTRACT FROM AUTHOR]

European ground squirrel (Spermophilus citellus) populations have declined precipitously over the last 70 years. Its protection cannot be ensured solely by protecting its habitat; it is also necessary to protect the animals ex situ. In our study, within a European ground squirrel species protection program, we examined two elements of indoor housing technology. Knowledge of the animals' needs is essential for captive housing and breeding success, so in our tests, the animals could freely choose both nest-building materials and feed. In the nest material preference test, the animals could choose from three materials with different structures: paper, Lignocel and hay. In the feed preference test, the animals could also choose from three types of feed: commercial rabbit feed, complete rabbit feed and a natural feed mixture. The first two feeds were in granulated format, and the third was a grain feed mix. Among the nesting materials, they preferred hay, which allowed them to build better-quality nests. Among the feeds, they preferred the grain feed mix, the composition closest to their natural feed, and it was the only one that contained animal protein. Our results contribute to the successful maintenance and breeding the European ground squirrel in captivity. [ABSTRACT FROM AUTHOR]

Simple Summary: This study focuses on the spontaneous lesions observed in a captive colony of geriatric Julia Creek dunnarts, an endangered carnivorous marsupial. Despite their conservation status, no prior research has focused on the conditions affecting captive individuals attaining senescence. We examined one wild and thirty-five captive-born, mostly elderly dunnarts that failed to reproduce over several breeding periods. From these, ten dunnarts had normal findings. Among females, the most common issue was cystic glandular hyperplasia (eight cases); cutaneous lesions were infrequent (two cases). Males showed testicular degeneration, aspermatogenesis, or atrophy (three cases). Cutaneous lesions compatible with epitheliotropic T cell lymphomas were observed in both sexes (five cases) and thus, an underlying oncogenic viral etiology is suspected. This is the first study that documents spontaneous diseases in aging Julia Creek dunnarts, shedding light on geriatric conditions within a conservation context. Julia Creek dunnarts are an endangered species of carnivorous marsupials and the focus of multiple conservation strategies involving significant resources such as captive breeding programs. Despite the relevance for conservation, no study to date has focused on evaluating geriatric diseases in dunnarts. This study describes the pathology findings in a group of one wild and thirty-five captive-born, mostly geriatric Julia Creek dunnarts that failed to produce offspring over multiple breeding periods. A total of 20 females and 16 males were submitted for a postmortem examination, with ages ranging from 9 to 42 and 12 to 42 months for females and males, respectively. Of these, 10 had unremarkable findings. The most common condition in females was cystic glandular hyperplasia (n = 8), typical of hormonal dysregulation profiles in senescence, particularly hyperestrogenism. Rarely, cutaneous disease represented by unidentified dermal round cell infiltrates was observed in females (n = 2). Primary reproductive hormonal dysregulation was also suspected in males diagnosed with testicular degeneration, aspermatogenesis and/or atrophy (n = 3). Cutaneous round cell infiltrates, possibly compatible with epitheliotropic lymphomas, were seen in males (n = 3), and 2/3 affected males also had concurrent testicular degeneration or atrophy, indicating male sex could be a predictor for lymphoid neoplasia in aged dunnarts, especially in individuals with concurrent testosterone-luteinizing hormone dysregulation as it occurs in gonadectomized animals. The role of an underlying viral etiology is also explored. This study is the first to describe major spontaneous diseases in endangered aged Julia Creek dunnarts, providing an important understanding of senescence and geriatric diseases within a conservation context. [ABSTRACT FROM AUTHOR]

Demand for wildlife and their products continues to grow, often despite increasingly militarised regulation and consumer awareness campaigns. We review the sustainability, legality and feasibility of wildlife farming of animals, as a potential conservation tool to ensure the development of an equitable and sustainable trade model.While there are some positive examples of well‐managed wildlife farming in trade, we identify common themes of misuse including the intentional mislabelling of wild‐caught specimens in global trade and the use of wild‐caught individuals to supplement captive stocks.We also highlight the frequent failure to incorporate biological data into management strategies, resulting in the widespread use of species with potentially unfavourable life history traits, which constrain the economic and biological sustainability of wildlife farming programmes.We develop a structured decision framework to aid the examination of when wildlife farming may most benefit or hinder species conservation.Synthesis and applications. Key opportunities include developing species suitability assessments and removing barriers to legitimate participation with wildlife farming among poor, rural communities. In the absence of management strategies that address the issues of species suitability and accessibility, wildlife farming will continue to place significant strain on wild populations while failing to provide conservation value and sustainable economic returns. Read the free Plain Language Summary for this article on the Journal blog. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Translocation of captive-bred animals is a widely used conservation strategy to support the recovery of imperiled wild populations. Identifying which factors enhance or limit survival after release can be important in adapting translocation strategies, particularly for species with low survival rates after release from captivity. Many translocation programs track post-translocation survival, but few complete spatial-statistical assessments of mortality risk associated with release environments. Typically, few animals are released from captive breeding programs, limiting the sample size available for analyses. We aimed to create a workflow that used limited datasets to evaluate the influence of spatial conditions and other factors on mortality risk. Greater sage-grouse (Centrocercus urophasianus) are endangered in Canada and of conservation concern throughout their range in the United States. After the species declined precipitously in Canada, a captive breeding program was initiated with subsequent releases in Alberta and Saskatchewan. Despite success in captive breeding, mortality rates of released sage-grouse were high. We used GPS- and VHF-based locations of released sage-grouse to determine how spatial features influence mortality risk of sage-grouse after release from captivity. We implemented a multistep approach to quantify and map risk relative to the environmental features associated with mortality. We also assessed whether the movement behaviors of sage-grouse correspond with environmental risk factors by using a combination of survival models and integrated step-selection functions. Mortality of sage-grouse in Alberta was hastened in areas close to anthropogenic disturbance. Although birds in Alberta avoided areas of higher mortality risk, those in Saskatchewan did not, perhaps due to environmental and selection constraints. This multistep approach allowed us to utilize small sample sizes to assess key risk factors in the landscape. This process supports the adaptive modification of translocation plans and can similarly support other data-limited scientists and managers in assessing environmental mortality risk and defining conservation actions for endangered species.

The Brazilian Merganser (Mergus octosetaceus) is one of the rarest birds in South America, and it is a critically endangered Anatidae species with an estimated population of less than 250 adult individuals in the Brazilian Cerrado. A captive population was established a few years ago at Zooparque Itatiba (São Paulo state) where 46 individuals were kept, and the founding population (progenitors derived from nature) was composed of 19 of the ex situ birds, derived from the four remaining localities with wild populations in Brazil. To characterize the genetic diversity and the genealogical relationships of the captive population, it is essential to conduct appropriate ex situ management and to assist future reintroduction projects. Thus, we have identified 425 SNPs by massively parallel sequencing of ddRAD libraries that allowed us to genotype individuals of the captive population. We observed a close relatedness between 70% of the captive population and founding individuals of Jalapão and Alto Paranaiba localities, indicating the need for supplementation with individuals from other areas of Canastra and Veadeiros. Even though many captives present a high level of inbreeding, we have identified some individuals with a high genetic value (less inbred) that can be selected for the breeding program to generate individuals for a future pilot reintroduction project.

Two subspecies of Saker Falcon are commonly accepted - Western (Falco cherrug cherrug) and Eastern (Falco cherrug milvipes), which are differentiated by their distribution range and phenotype. In Bulgaria, Western Saker Falcons are breeding ex situ in the Wildlife Rehabilitation and Breeding Centre, part of Green Balkans - Stara Zagora NGO, with the aim of restoring the nesting population of the species in the country and both Western and Eastern - in the Breeding Centre for Birds of Prey in Burgas for the purpose of sale for the needs of falconry in the country and abroad. In 2021, a total of 115 birds from the two breeding centres were sampled. The samples were analysed in Bielefeld University (Germany) at nine microsatellite loci. Structure analyses were performed to establish the optimal explanatory number of groups. We compared the putative genetic groups with the known/expected origin of falcons. A separation in two groups best explained the allelic variation between samples. Out of 68 Saker Falcons with putatively Eastern origin, 66 were ascribed to genetic group 2 and two falcons had unclear, mixed or hybrid genetic fingerprints. Out of 42 Sakers with putatively Western origin, 33 were ascribed to genetic group 1, seven to genetic group 2 and two individuals appeared to have a mixed signature of genetic groups 1 and 2 with dominating alleles of group 2. Five known hybrids were scored as mixed signature with dominating genetic cluster 2. This suggests that the two (Eastern and Western) populations of Saker Falcon origin suggested by the subspecies' definitions are also adequate to be considered in breeding programmes. Genetic cluster 1 might represent the ancestral alleles shared with other falcons, while specific novel alleles allow the discrimination of secured Eastern Sakers (group 2), while these populations may be occasionally invaded by individuals from the west.

Parrots are popular with pet consumers and are one of the most traded groups of live birds around the world. China has been considered as an important country in bird trades, but we know little about China’s import and export of parrots. Using the latest data available from the CITES Trade Database, we analyzed China’s import and export of CITES-listed live parrots from 1981–2022 to better understand the patterns and dynamics of these trades. China imported 155,339 parrots of 173 species and exported 608,987 parrots of 42 species during the study period with an annual average of about 18,500 individuals, accounting for c. 5% of the global average number. The most imported parrots to China were Grey Parrot (Psittacus erithacus) and Monk Parakeet (Myiopsitta monachus), while the most exported ones were Fisher’s Lovebirds (Agapornis fischeri), Rosy-faced Lovebirds (Agapornis roseicollis), and Yellow-collared Lovebird (Agapornis personatus). Since the early 21st century, China’s imports of parrots gradually increased, but exports decreased more pronouncedly, making China’s international parrot trade volume declining in the past 20 years. China’s international parrot trade routes also changed over time, with the destination of parrot exports shifting from Europe to Africa and the Arabian region, while more parrots being gradually imported from countries in South America and Africa. The vast majority of parrots exported from China were captive-bred non-native species like Fisher’s Lovebirds, while a substantial proportion of imported parrots were wild-sourced and the proportion has been increasing in the last decade. The fact that China exported much more parrots than imported suggests existence of large-scale parrot farming and domestic parrot trade in China. Attention needs to be paid to monitoring China’s import of increasing proportion of wild-sourced parrots from South America countries and its potential impacts on their wild populations. Close monitoring of and more studies on domestic and illegal parrot trade are essential to fully understand the role China plays in the international trade of parrots.

Simple Summary: We used 46 individuals of the critically endangered Brazilian Merganser, currently endemic to the Cerrado biome in Brazil, to understand genetic diversity and the genealogical relationships of the captive population. By characterizing 425 genomic variants in these captive specimens, our study unveiled a significant level of inbreeding, with approximately 70% of the captive birds tracing their lineage back to the founders from just two localities. Leveraging the identified DNA variants, we also identified less inbred individuals suitable for the potential future reintroduction into the wild. The Brazilian Merganser (Mergus octosetaceus) is one of the rarest birds in South America, and it is a critically endangered Anatidae species with an estimated population of less than 250 adult individuals in the Brazilian Cerrado. A captive population was established a few years ago at Zooparque Itatiba (São Paulo state) where 46 individuals were kept, and the founding population (progenitors derived from nature) was composed of 19 of the ex situ birds, derived from the four remaining localities with wild populations in Brazil. To characterize the genetic diversity and the genealogical relationships of the captive population, it is essential to conduct appropriate ex situ management and to assist future reintroduction projects. Thus, we have identified 425 SNPs by massively parallel sequencing of ddRAD libraries that allowed us to genotype individuals of the captive population. We observed a close relatedness between 70% of the captive population and founding individuals of Jalapão and Alto Paranaiba localities, indicating the need for supplementation with individuals from other areas of Canastra and Veadeiros. Even though many captives present a high level of inbreeding, we have identified some individuals with a high genetic value (less inbred) that can be selected for the breeding program to generate individuals for a future pilot reintroduction project. [ABSTRACT FROM AUTHOR]