Review of hyperdispersal in wildlife translocations

Species translocation is a common tool to reverse biodiversity loss, but it has a high failure rate. One factor that contributes to failure is postrelease hyperdispersal, which we define as the long-distance movement of individuals resulting in their failure to contribute to population establishment. We reviewed reported incidences of hyperdispersal and compared rates of hyperdispersal among taxa, population demographics, release cohorts, and success of mitigation techniques. Of 151 conservation translocations (reinforcements and reintroductions) in which animals were tracked, hyperdispersal was confirmed in 52.1% of programs. The prevalence of hyperdispersal (percentage of studies) was relatively consistent across taxa (42.9-60%), but hyperdispersal rates in birds were likely underestimated because 76.9% of bird translocations showed incidences in which birds could not be located after release, but hyperdispersal was unable to be confirmed. Eutherians exhibited a higher average incidence of hyperdispersal (percentage of hyperdispersing individuals in a cohort) of 20.2% than birds, reptiles, and marsupials (10.4%, 15.7%, and 10.3%, respectively). No significant trends were observed for sex, source population, or translocation type, but there were nonsignificant trends for males to hyperdisperse more than females and for higher incidences of hyperdispersal in reinforcements relative to reintroduction programs. Mitigation techniques included temporary confinement, supplementation of resources, and releasing animals in social groups, but only half of studies examining mitigation techniques found them useful. Hyperdispersal incidence was variable within taxa, and we advise against forming translocations strategies based on results from other species. Hyperdispersal is a significant welfare, economic, and conservation issue in translocations, and we suggest definitions, reporting, and experimental strategies to address it.

Return to 1616: Multispecies Fauna Reconstruction Requires Thinking Outside the Box

Conservation translocations have become increasingly popular for 'rewilding' areas that have lost their native fauna. These multispecies translocations are complex and need to consider the requirements of each individual species as well as the influence of likely interactions among them. The Dirk Hartog Island National Park Ecological Restoration Project, Return to 1616, aspires to restore ecological function to Western Australia's largest island. Since 2012, pest animals have been eradicated, and conservation translocations of seven fauna species have been undertaken, with a further six planned. Here, we present a synthesis of the innovative approaches undertaken in restoring the former faunal assemblage of Dirk Hartog Island and the key learnings gathered as the project has progressed.

The endangered brain: actively preserving ex-situ animal behaviour and cognition will benefit in-situ conservation

Endangered species have small, unsustainable population sizes that are geographically or genetically restricted. Ex-situ conservation programmes are therefore faced with the challenge of breeding sufficiently sized, genetically diverse populations earmarked for reintroduction that have the behavioural skills to survive and breed in the wild. Yet, maintaining historically beneficial behaviours may be insufficient, as research continues to suggest that certain cognitive-behavioural skills and flexibility are necessary to cope with human-induced rapid environmental change (HIREC). This paper begins by reviewing interdisciplinary studies on the 'captivity effect' in laboratory, farmed, domesticated and feral vertebrates and finds that captivity imposes rapid yet often reversible changes to the brain, cognition and behaviour. However, research on this effect in ex-situ conservation sites is lacking. This paper reveals an apparent mismatch between ex-situ enrichment aims and the cognitive-behavioural skills possessed by animals currently coping with HIREC. After synthesizing literature across neuroscience, behavioural biology, comparative cognition and field conservation, it seems that ex-situ endangered species deemed for reintroduction may have better chances of coping with HIREC if their natural cognition and behavioural repertoires are actively preserved. Evaluating the effects of environmental challenges rather than captivity per se is recommended, in addition to using targeted cognitive enrichment.

Tracking the global application of conservation translocation and social attraction to reverse seabird declines

The global loss of biodiversity has inspired actions to restore nature across the planet. Translocation and social attraction actions deliberately move or lure a target species to a restoration site to reintroduce or augment populations and enhance biodiversity and ecosystem resilience. Given limited conservation funding and rapidly accelerating extinction trajectories, tracking progress of these interventions can inform best practices and advance management outcomes. Seabirds are globally threatened and commonly targeted for translocation and social attraction ("active seabird restoration"), yet no framework exists for tracking these efforts nor informing best practices. This study addresses this gap for conservation decision makers responsible for seabirds and coastal management. We systematically reviewed active seabird restoration projects worldwide and collated results into a publicly accessible Seabird Restoration Database. We describe global restoration trends, apply a systematic process to measure success rates and response times since implementation, and examine global factors influencing outcomes. The database contains 851 active restoration events in 551 locations targeting 138 seabird species; 16% of events targeted globally threatened taxa. Visitation occurred in 80% of events and breeding occurred in 76%, on average 2 y after implementation began (SD = 3.2 y). Outcomes varied by taxonomy, with the highest and quickest breeding response rates for Charadriiformes (terns, gulls, and auks), primarily with social attraction. Given delayed and variable response times to active restoration, 5 y is appropriate before evaluating outcomes. The database and results serve as a model for tracking and evaluating restoration outcomes, and is applicable to measuring conservation interventions for additional threatened taxa.

Lessons Learned for Pre-Emptive Capture Management as a Tool for Wildlife Conservation during Oil Spills and Eradication Events

Pre-emptive capture or translocation of wildlife during oil spills and prior to pest eradication poison applications are very specific conservation goals within the field of conservation translocation/reintroduction. Protection of wildlife from contamination events occurs during either planned operations such as pest eradication poison applications, or unplanned events such as pollution or oil spills. The aim in both incidences is to protect at-risk wildlife species, ensuring the survival of a threatened regional population or entire species, by excluding wildlife from entering affected areas and therefore preventing impacts on the protected wildlife. If pre-emptive capture does not occur, wildlife may unintentionally be affected and could either die or will need capture, cleaning, and/or medical care and rehabilitation before being released back into a cleared environment. This paper reviews information from pre-emptive captures and translocations of threatened wildlife undertaken during past oil spills and island pest eradications, to assess criteria for species captured, techniques used, outcomes of responses, and lessons learned. From these case studies, the considerations and planning needs for pre-emptive capture are described and recommendations made to allow better use and preparedness for pre-emptive capture as a preventative wildlife conservation tool.

Using a substitute species to inform translocation of an endangered territorial mammal

Substitute species can inform management strategies without exposing endangered species to unacceptable risk. Furthermore, experimental approaches may help to identify the causes of translocation failures, improving the chances of success. We used a surrogate subspecies, Tamiasciurus fremonti fremonti to test different translocation techniques to inform on potential management actions with regards to the endangered Mt. Graham red squirrel (Tamiasciurus fremonti grahamensis). Individuals of both subspecies defend year-round territories in similar mixed conifer forests at elevations between 2650-2750 m, where they store cones to survive over winter. We fitted VHF radio collars to 54 animals, and we monitored their survival and movements until individuals settled on a new territory. We considered the effect of season, translocation technique (soft or hard release), and body mass on survival, distance moved after release, and time to settlement of translocated animals. Survival probability averaged 0.48 after 60 days from the translocation event and was not affected by season or translocation technique. 54% of the mortality was caused by predation. Distance moved and number of days to settlement varied with season, where winter was characterized by shorter distances (average of 364 m in winter versus 1752 m in fall) and a smaller number of days (6 in winter versus 23 in fall). The data emphasized on the potential of substitute species to provide valuable information for possible outcomes of management strategies to closely related endangered species.

The Role of Zoos and Aquariums in a Changing World

Zoos and aquariums have evolved significantly. From their origins as enclosures for the mere entertainment of the public, these institutions have undertaken new functions responding to the biodiversity crisis and social demands. Modern zoos and aquariums have the opportunity to educate people, contribute to species conservation, and produce animal-related research. However, there is increasing criticism toward the outcomes of their actions and the holding of species in their facilities. This review offers an integrated analysis of the state of knowledge about the role that zoos and aquariums play today. It describes their performance regarding their conservation, education, and research functions, highlighting general patterns and offering future perspectives. It identifies some challenges common to all these institutions, concluding that the way they keep up with the ever-growing social and environmental expectations will be decisive hereafter.

Social feasibility assessments in conservation translocations

Improving the effectiveness of conservation translocations could contribute to reversing global biodiversity loss. Although evaluations of ecological factors affecting translocation outcomes are commonplace, consideration of human social factors remains rare, hindering improvements to this conservation practice. We analysed 550 translocation case studies to explore the inclusion of social factors in project feasibility assessments. Reviewed projects often failed to assess social feasibility, and assessments, where attempted, tended to be narrow in scope. Consequently, challenges such as proactively addressing conflict often remained unaddressed. Insufficient knowledge sharing and prioritisation of ecological feasibility, to the detriment of social feasibility, remain barriers to effective planning. Successful outcomes of translocations are linked to early assessment of social feasibility and to the establishment of long-term commitments between people, places, and partners.

Current genetic structure of European vendace Coregonus albula (L.) populations in Latvia after multiple past translocations

The European vendace Coregonus albula (L.), also known as the European cisco, is a widespread fish species in northern Europe, often regarded as an example of a glacial relict. It is an economically valuable fish and has been artificially propagated in Latvia since 1900. Despite past translocations of larvae and fry and its current protection status, it can be found in only 15 Latvian lakes. We used nine microsatellite markers to study vendace populations from nine Latvian lakes. A higher mean allelic richness and private allelic richness in Lake Riču suggest that this population may be indigenous. Three complementary clustering methods revealed similar grouping into three distinct genetic groups. According to the results, European vendace populations in the Latvian lakes studied may currently be a mixture of several other populations after multiple translocations.

Animal Personality and Conservation: Basics for Inspiring New Research

Simple Summary

The study of animal personality is important to conserve animals because it can help in selecting the most appropriate individuals to be released into the wild. Individuals not so bold or aggressive, less stressed, who explore their new environment with greater caution are often more likely to survive after release into the wild. In contrast, bolder and more aggressive animals reproduce more successfully and, therefore, can be released with the aim of rapid repopulation of an area. These and other aspects of how animal personality can help in conservation programs, as well as how to collect personality data are covered in this paper.

Abstract

The number of animal species threatened with extinction are increasing every year, and biologists are conducting animal translocations, as one strategy, to try to mitigate this situation. Furthermore, researchers are evaluating methods to increase translocation success, and one area that shows promise is the study of animal personality. Animal personality can be defined as behavioral and physiological differences between individuals of the same species, which are stable in time and across different contexts. In the present paper, we discuss how animal personality can increase the success of translocation, as well as in the management of animals intended for translocation by evaluating personality characteristics of the individuals. Studies of the influence of birthplace, parental behavior, stress resilience, and risk assessment can be important to select the most appropriate individuals to be released. Finally, we explain the two methods used to gather personality data.