Welfare based primate rehabilitation as a potential conservation strategy: does it measure up?

Many primate species are threatened with extinction and are the focus of extensive conservation efforts including re-introduction, captive breeding and habitat conservation. Welfare-based rehabilitation (hereafter also ‘rehabilitation’) is a management strategy commonly used for primates, particularly those species targeted by the pet and bush meat trades. Rehabilitation of rescued primates typically has the dual motivation of welfare and conservation, but has not been assessed as a conservation strategy. As the species involved in rehabilitation are often endangered (e.g. chimpanzees, gorillas, orang-utans), it is important for rehabilitation projects to follow a ‘best practice’ model in order to increase positive outcomes. In this study, we compared the approaches of 28 welfare-based primate rehabilitation projects to the ‘IUCN guidelines for nonhuman primate re-introductions’, in addition to components of the ‘Best practice guidelines for the re-introduction of great apes’ in order to assess where additional work might be needed for released animals to contribute to conservation outcomes. Few projects examined complied with the guidelines for re-introduction, failing to incorporate important factors such as quarantine, long term post-release monitoring and training for predator awareness. Further development of species-specific rehabilitation guidelines may improve the outcomes of future rehabilitation projects. To support this, we recommend that detailed methods and results be published for all rehabilitation efforts, regardless of the outcome.     

Translocations of digging mammals and their potential for ecosystem restoration: a review of goals and monitoring programmes

1. Globally, translocations are commonly used to improve the conservation status of threatened species. There is increasing recognition that translocations of ecosystem engineers also have the potential to restore ecological processes. Digging mammals are often considered to be ecosystem engineers, as their diggings provide shelter for other species and can significantly alter soil properties, with subsequent changes to vegetation.
2. Using Australian species as a case study, we reviewed published and grey literature on digging mammal translocations to determine how often these translocations are conducted to restore ecosystem processes. We documented ecosystem-level monitoring and research efforts, and assessed whether restoration was perceived to be occurring post-release.
3. At least 208 translocations of 24 digging mammal species have been conducted in Australia, with a further 38 planned for the near future. Prior to 2019, only 3% of translocations included a goal relating to the restoration of ecosystem processes associated with digging activities. Nearly a quarter of pre-2019 translocations have been the subject of some form of ecosystem-level monitoring or research, but long-term ecosystem-level monitoring was very rare. In contrast, 74% of the translocations planned for post-2018 include a goal relating to the restoration of ecological processes and most also include plans to conduct ecosystem-level monitoring.
4. Ecosystem restoration was perceived to be occurring for 26% of the pre-2019 translocations. None of the documents we reviewed indicated that ecological degradation had occurred post-translocation, even when declines in other taxa were recorded.
5. The restoration of ecosystem processes is increasingly being identified as a goal for translocation programmes. Where this is the case, we suggest that translocation practitioners include success criteria for the restoration of ecosystem processes, and commit to long-term monitoring designed to detect ecosystem-level effects of translocations.

     

Lessons from practice: assessing early progress and success in river rehabilitation

This article comprises a literature analysis of 41 river rehabilitation projects to assess the short-term (5 years) ability of indicator groups to demonstrate progress towards river rehabilitation goals. Positive indications were compared to land-use, river size, rehabilitation intervention and time. A questionnaire was developed to investigate river manager’s interpretation of rehabilitation success and to assess their level of adherence to recommendations in the literature with regard to rehabilitation assessment on a conceptual level. A total of 54 responses were received from respondents based in Germany, The Netherlands and the United Kingdom. The results indicate that macroinvertebrate indicators, while widely used in assessing river rehabilitation efforts, exhibited a lower frequency of positive responses than most other indicator types in the short term. Conversely, terrestrial floodplain indicators exhibited the most frequent level of positive response for all ecological type indicators leading to recommendations for further investigations into their use for short-term monitoring. Assessment procedures recommended in literature are largely followed, illustrating the advances that have been made with regard to assessment planning. Indicator responses are influenced by scale factors, for example, land-use and river size, that are often not considered by rehabilitation managers. While an emphasis is placed on ecological, hydrological and morphological indicators in monitoring schemes, the socioeconomic perspective (emphasized in the literature as forming an integral part of the river system) is neglected.     

Behavioral Adaptation of Pan troglodytes troglodytes

As wild primate populations decline, numbers of orphaned primates, sanctuaries, and attempts to release primates back to the natural environment increase. Release projects frequently are poorly documented despite IUCN guidelines recommending post-release monitoring and systematic data collection as central to the process. Since 1996, Habitat Ecologique et Liberté des Primates (HELP) has been releasing wild-born orphaned chimpanzees into natural habitat in the Conkouati-Douli National Park, Republic of Congo. HELP developed a post-release monitoring system as an integral component. We present activity budgets and diet of released chimpanzees, and compared them to those of wild chimpanzee, as primary indicators of successful release. Feeding, moving, and resting dominated activity budgets, reflecting the overall patterns in wild populations. Diet was diverse and dominated by fruit, and the released chimpanzees showed specialization on a smaller number of species, as in many wild communities. The high survival rates of the chimpanzees and overall success of the release program are attributed to careful planning and post-release support facilitated via the monitoring process. Systematic post-release data collection monitoring has confirmed that wild-born chimpanzees can adjust behaviorally and nutritionally to the wild. Survival statistics of the reintroduced chimpanzees—confirmed 56%, possible 88%— reflect the behavioral adaptability.2nd revision March 11, 2005An erratum to this article can be found at     

Reading Mammal Diversity from Flies: The Persistence Period of Amplifiable Mammal mtDNA in Blowfly Guts (Chrysomya megacephala) and a New DNA Mini-Barcode Target

Most tropical mammal species are threatened or data-deficient. Data collection is impeded by the traditional monitoring approaches which can be laborious, expensive and struggle to detect cryptic diversity. Monitoring approaches using mammal DNA derived from invertebrates are emerging as cost- and time-effective alternatives. As a step towards development of blowfly-derived DNA as an effective method for mammal monitoring in the biodiversity hotspot of Peninsular Malaysia, our objectives were (i) to determine the persistence period of amplifiable mammal mtDNA in blowfly guts through a laboratory feeding experiment (ii) to design and test primers that can selectively amplify mammal COI DNA mini-barcodes in the presence of high concentrations of blowfly DNA. The persistence period of amplifiable mammal mtDNA in blowfly guts was 24 h to 96 h post-feeding indicating the need for collecting flies within 24 h of capture to detect mammal mtDNA of sufficient quantity and quality. We designed a new primer combination for a COI DNA mini-barcode that did not amplify blowfly DNA and showed 89% amplification success for a dataset of mammals from Peninsular Malaysia. The short (205 bp) DNA mini-barcode could distinguish most mammal species (including separating dark taxa) and is of suitable length for high-throughput sequencing. Our new DNA mini-barcode target and a standardized trapping protocol with retrieval of blowflies every 24 h could point the way forward in the development of blowfly-derived DNA as an effective method for mammal monitoring.     

Monitoring for the Management of Disease Risk in Animal Translocation Programmes

Monitoring is best viewed as a component of some larger programme focused on science or conservation. The value of monitoring is determined by the extent to which it informs the parent process. Animal translocation programmes are typically designed to augment or establish viable animal populations without changing the local community in any detrimental way. Such programmes seek to minimize disease risk to local wild animals, to translocated animals, and in some cases to humans. Disease monitoring can inform translocation decisions by (1) providing information for state-dependent decisions, (2) assessing progress towards programme objectives, and (3) permitting learning in order to make better decisions in the future. Here we discuss specific decisions that can be informed by both pre-release and post-release disease monitoring programmes. We specify state variables and vital rates needed to inform these decisions. We then discuss monitoring data and analytic methods that can be used to estimate these state variables and vital rates. Our discussion is necessarily general, but hopefully provides a basis for tailoring disease monitoring approaches to specific translocation programmes.     

Genome scale assessment of a species translocation program

Despite increased use of species translocations, controversy remains regarding the efficacy and efficiency of the strategy in obtaining conservation goals. Much of this controversy results from vague program objectives, unclear definitions of success, and lack of follow-up monitoring. We used the translocation program initiated by Zoo Knoxville for the federally threatened Bog Turtle (Glyptemys muhlenbergii) as a case study to demonstrate how genomic assessments not only assess the success of program objectives, but also allow managers to quickly obtain baseline data from which program objectives and explicit definitions of ‘success’ can be determined. Here we used 7030 SNP markers derived from RADseq data to confirm the premise that different source populations are genetically differentiated. Then we tested whether the release population has enhanced genetic diversity, as expected from a deliberate admixture. Although the release population had greater diversity than any source population, variation was lower than expected from modeling admixture with equal source contribution. Our results support the premise that genetic diversity can be maximized by including representatives from as many natural populations as possible. But failure to achieve the expected level of diversity could result from nonrandom success of founders from different sources or unrecorded bias in the implementation of the release program. Many existing and future translocation programs would benefit from genetic assessment similar to that conducted here with Bog Turtles.     

Assortative mating among animals of captive and wild origin following experimental conservation releases

Captive breeding is a high profile management tool used for conserving threatened species. However, the inevitable consequence of generations in captivity is broad scale and often-rapid phenotypic divergence between captive and wild individuals, through environmental differences and genetic processes. Although poorly understood, mate choice preference is one of the changes that may occur in captivity that could have important implications for the reintroduction success of captive-bred animals. We bred wild-caught house mice for three generations to examine mating patterns and reproductive outcomes when these animals were simultaneously released into multiple outdoor enclosures with wild conspecifics. At release, there were significant differences in phenotypic (e.g. body mass) and genetic measures (e.g. G_st and F) between captive-bred and wild adult mice. Furthermore, 83% of offspring produced post-release were of same source parentage, inferring pronounced assortative mating. Our findings suggest that captive breeding may affect mating preferences, with potentially adverse implications for the success of threatened species reintroduction programmes.     

Behavioral considerations of headstarting as a conservation strategy for endangered Caribbean rock iguanas

Headstarting animals in captivity prior to reintroduction into the wild has proven to be a valuable strategy in the conservation of critically endangered Caribbean rock iguanas (genus Cyclura). However, a major concern associated with headstarting programs is that some animals reared in a captive environment may lack the behavioral competency to survive and reproduce following release into the wild. Rock iguana headstarting programs are reviewed in terms of assessment and potential enhancement of behavioral competency both pre- and post-release. It may be possible to induce more highly developed antipredator behavior through carefully designed training programs, well-planned enclosures, and site-specific release strategies. Post-release foraging competency can likely be augmented by exposing release candidates to a wider range of natural food types prior to release and timing releases to coincide with periods of seasonal food abundance. The probability of successful settlement and social integration into the wild population may be increased through pre-release exposure to key biotic and abiotic environmental cues, spatial and temporal release strategies, and selection of appropriate release candidates. While empirical results to date suggest that Caribbean rock iguanas are prime candidates for headstart-release programs, avenues for future research are explored that could help enhance restoration success.     

On the merits and feasibility of wildlife monitoring for conservation: a case study from Katavi National Park,Tanzania

Although long‐term monitoring is viewed as an essential part of conserving wildlife populations, it is currently carried out in surprisingly few protected areas in Africa. Here, data from a 16‐year vehicle transect monitoring programme in Katavi National Park, western Tanzania, are presented. These data provide information on large mammal densities, identify declines in populations of several large mammal species as based on encounter rates, support worrying trends observed in aerial census data and shed light on the effectiveness of recent changes in legal protection. Ground and aerial surveys confirmed that waterbuck, topi, warthog, lion and spotted hyaena populations are all in decline and that this should be a cause for concern. Counting animals by driving vehicle transects is relatively easy and inexpensive to carry out, and data here show that such counts have several pay‐offs for conservation managers especially in identifying population declines; counts should be employed more often in East Africa and elsewhere.     

Measuring animal welfare within a reintroduction: an assessment of different indices of stress in water voles Arvicola amphibius

Reintroductions are an increasingly common conservation restoration tool; however, little attention has hitherto been given to different methods for monitoring the stress encountered by reintroduced individuals. We compared ten potential measures of stress within four different categories (neuroendocrine, cell function, body condition and immune system function) as proxies for animal welfare in water voles being reintroduced to the Upper Thames region, Oxfordshire, UK. Captive-bred voles were assessed pre-release, and each month post-release for up to five months. Wild-born voles were captured in the field and assessed from two months post-release. Plasma corticosteroid, hydration and body condition of captive-bred voles differed between their pre-release measures and both their first ("short-term") recapture, and their final recapture ("long-term" release), however only body condition and immunocompetence measured using the Nitroblue Tetrazolium (NBT) test were significantly different post-release between the first and last recaptures. Captive-bred animals had lower fat reserves, higher weight/length ratios and better immunocompetence (NBT) than did wild-born voles. Captive-bred males had higher ectoparasite burdens compared to wild-born males and, as reintroduction site quality decreased, became less hydrated. These observations indicate that some methods can identify changes in the stress response in individuals, highlighting areas of risk in a reintroduction programme. In addition, a single measure may not provide a full picture of the stress experienced; instead, a combination of measures of different physiological systems may give a more complete indication of stress during the reintroduction process. We highlight the need to monitor stress in reintroductions using measures from different physiological systems to inform on possible animal welfare improvements and thus the overall success rate of reintroductions.     

Release of rehabilitated Chlorocebus aethiops to Isishlengeni Game Farm in KwaZulu-Natal,South Africa

Chlorocebus aethiops are treated as vermin by some in South Africa, and this has resulted in injury, illness and death of hundreds of C. aethiops, with orphans being very common. Rehabilitation centres care for, rehabilitate and aim to return these monkeys to the wild. This study describes the release of 29 C. aethiops to Isishlengeni Game Farm in KwaZulu-Natal, South Africa. The troop was monitored for six months. Confirmed survival of the troop was 62%, with 17% suspected mortality and 21% of the troop unaccounted for. The release site was not ideal due to hunting activities, the proximity of dwellings and roads and the presence of a wild troop. Preparation for release could be improved through the provision of naturally occurring foods and pre-release disease screening. Post-release monitoring would greatly benefit from the use of tracking devices to allow all animals to be followed post-release.     

Evaluating the post-release efficacy of invasive plant biocontrol by insects: a comprehensive approach

We propose a comprehensive program to evaluate the post-release phase of biocontrol programs that use insect herbivores to control invasive plant species. We argue that any release should be done in randomized release and non-release sites and should be followed up by well-replicated sampling and experimental protocols that evaluate the degree of success or failure. These follow-up studies should include landscape scale monitoring across relevant habitat gradients of (1) the abundance of the biocontrol agent, (2) the impact of the biocontrol agent on the target plant species, (3) the potential for non-target effects, and (4) the response of native species and communities to a reduction in the invasive species. We also argue that (5) experimental reductions of the biocontrol agent are required to eliminate the chance that the putative impact of the biocontrol agent is not confounded with other causes. Finally, we describe six scenarios, informed largely by a community ecology perspective, in which a biocontrol agent may decrease the abundance or vigor of the target plant species but not lead to successful control where native communities re-establish. We classify these failure scenarios as either direct or indirect effects of the invasive plant species: Native Source Limitation, Static Competitive Hierarchies, Novel Weapons, Trophic Shifts, Invasive Engineering and Associated Invasives. Overall, we argue that well replicated and landscape-scale post release monitoring programs are required not only to evaluate critically the degree of success and failure of biocontrol programs worldwide but also to provide insights into improving future biocontrol efforts. Handling Editor: Heikki Hokkanen.     

Targeted detection of mammalian species using carrion fly‐derived DNA

DNA analysis from carrion flies (iDNA analysis) has recently been promoted as a powerful tool for cost‐ and time‐efficient monitoring of wildlife. While originally applied to identify any mammalian species present in an area, it should also allow for targeted detection of species and individuals. Using carrion flies captured in the Taï National Park, Côte d'Ivoire, we assessed this possibility by (i) screening carrion fly DNA extracts with nonspecific and species‐specific PCR systems, respectively, targeting mitochondrial DNA (mtDNA) fragments of any mammal or of Jentink's duiker (Cephalophus jentinki), three colobine monkeys (subfamily Colobinae) and sooty mangabey (Cercocebus atys); and (ii) genotyping carrion fly extracts containing sooty mangabey mtDNA. In comparison with the nonspecific PCR assay, the use of specific PCRs increased the frequency of detection of target species up to threefold. Detection rates partially reflected relative abundances of target species in the area. Amplification of seven microsatellite loci from carrion flies positive for sooty mangabey mtDNA yielded an average PCR success of 46%, showing that the identification of individuals is, to some extent, possible. Regression analysis of microsatellite PCR success and mtDNA concentration revealed that, among all carrion flies analysed for this study, 1% contained amounts of mammal mtDNA sufficient to attempt genotyping with potentially high success. We conclude that carrion fly‐derived DNA analysis represents a promising tool for targeted monitoring of mammals in their natural habitat.     

Mammals at rescue centres in the Czech Republic: Trends in intake and outcome,causes of admission,length of stay and release rate

Rescue centres in the Czech Republic care for injured, young uninjured, and otherwise physically damaged wild animals that are temporarily or permanently incapable of looking after themselves without assistance or incapable of surviving in the wild. We evaluated the numbers of mammals admitted to 37 rescue centres in the Czech Republic in a ten year period from 2011 to 2020, the causes leading to the admission of these mammals to rescue centres, their outcomes and their length of stay at rescue centres. In total, 73,499 mammals were admitted to the Czech rescue centres in the monitored period, with an increasing trend being found in the number of admissions (rSp = 0.9030, p < 0.05). The mammals admitted in the largest numbers were Chiroptera (39.36%), primarily the common pipistrelle (Pipistrellus pipistrellus), and Insectivora (35.85%), of which the largest proportion was made up of European hedgehogs (Erinaceus europaeus). Although according to the IUCN classification only 0.26% of admitted animals belonged among Endangered or Critically Endangered species, according to the Czech legislation, 47.21% of admitted mammals belonged to species in varying degrees of endangerment in this area. The most frequent reasons for admission were the admission of young (33.18%) with differences between the Orders - the highest number of admitted young of Rodentia (72.66% of all admitted Rodentia) and the lowest number of young of Chiroptera (2.74%). Of all mammals admitted to rescue centres, 45.83% were released back into the wild, 24.52% died at rescue centres, and 9.50% were euthanized. The highest release rate was achieved in Chiroptera (74.60%) especially those that suffered from malnutrition (63.09% of all admitted Chiroptera due to malnutrition). The length of stay was longest in young Artiodactyla released back to the wild (median 87 days). The data obtained from rescue centres provide an overview of the numbers and species of animals admitted and the outcome of their rehabilitation. Since almost half of mammals admitted could not be returned to the wild, it is also important to determine correctly which individuals should be treated and what is the most efficient use of resources for wildlife rehabilitation.     

Threats to mangroves from climate change and adaptation options: A review

Mangrove ecosystems are threatened by climate change. We review the state of knowledge of mangrove vulnerability and responses to predicted climate change and consider adaptation options. Based on available evidence, of all the climate change outcomes, relative sea-level rise may be the greatest threat to mangroves. Most mangrove sediment surface elevations are not keeping pace with sea-level rise, although longer term studies from a larger number of regions are needed. Rising sea-level will have the greatest impact on mangroves experiencing net lowering in sediment elevation, where there is limited area for landward migration. The Pacific Islands mangroves have been demonstrated to be at high risk of substantial reductions. There is less certainty over other climate change outcomes and mangrove responses. More research is needed on assessment methods and standard indicators of change in response to effects from climate change, while regional monitoring networks are needed to observe these responses to enable educated adaptation. Adaptation measures can offset anticipated mangrove losses and improve resistance and resilience to climate change. Coastal planning can adapt to facilitate mangrove migration with sea-level rise. Management of activities within the catchment that affect long-term trends in the mangrove sediment elevation, better management of other stressors on mangroves, rehabilitation of degraded mangrove areas, and increases in systems of strategically designed protected area networks that include mangroves and functionally linked ecosystems through representation, replication and refugia, are additional adaptation options.     

Introduced mammals in Australian rangelands: Future threats and the role of monitoring programmes in management strategies

Abstract In the present paper, we have provided an initial assessment of the current and future threats to biodiversity posed by introduced mammals (predators and herbivores) inhabiting the Australian rangelands, exploring trends in populations and options for management. Notably, rabbits have declined in recent years in the wake of rabbit haemorrhagic disease, populations of feral camels have increased dramatically and foxes appear to have moved northwards, thereby threatening native fauna within an expanded range. Following on, we developed a framework for monitoring the impacts of introduced mammals in the Australian rangelands. In doing so, we considered the key issues that needed to be considered in designing a monitoring programme for this purpose and critically evaluated the role of monitoring in pest animal management. Finally we have provided a brief inventory of current best‐practice methods of estimating the abundance of introduced mammal populations in the Australian rangelands with some comments on new approaches and their potential applications.     

Biology and behaviour of reintroduced gibbons

We observed and recorded the behaviours of gibbons undergoing rehabilitation, before and after release, to document the behavioural and social changes of gibbons in the rehabilitation program and develop criteria for determining the suitability of a pair of gibbons for release. Hylobates albibarbis were observed at the Kalaweit Gibbon Rehabilitation Project in Kalimantan, Indonesia. Data were collected on animals both pre- and post-release and on wild gibbons for comparison. Data presented here show that reintroduced gibbons are capable of surviving without human intervention. In addition, their behaviour is similar to that of wild gibbons in terms of activity budgets, position in the canopy, body posture, pair association (PA) and diet. Prior to this study, no attempt has been made to quantify the rehabilitation process for gibbons, and rehabilitation project personnel require data reporting all aspects of a release so that improvements can be made. It is important to report these data for the benefit of future releases. Criteria, based on the behaviour of wild gibbons, are proposed to assist rehabilitation centers in assessing the suitability of gibbon pairs for release.     

The reintroduction of the Eurasian otter (Lutra lutra) into the Netherlands: hidden life revealed by noninvasive genetic monitoring

The last recorded presence of the Eurasian otter (Lutra lutra) in the Netherlands dates from 1989 and concerned a dead individual. In 2002 a reintroduction programme was started, and between June 2002 and April 2008 a total of 30 individuals (10 males and 20 females) were released into a lowland peat marsh in the north of the Netherlands. Noninvasive genetic monitoring based on the genetic profiles obtained from DNA extracted from otter faeces (spraints) was chosen for the post-release monitoring of the population. To this end, the founding individuals were genotyped before release and spraints were collected in the release area each winter from 2002 to 2008. From June 2002 to April 2008 we analysed the genetic profile of 1,265 spraints on the basis of 7–15 microsatellite loci, 582 of which (46%) were successfully assigned to either released or newly identified genotypes. We identified 54 offspring (23 females and 31 males): the females started to reproduce after 2 years and the males after 4 years. The mating and reproductive success among males was strongly skewed, with a few dominant males fathering two-thirds of the offspring, but the females had a more even distribution. The effective population size (Ne) was only about 30% of the observed density (N), mainly because of the large variance in reproductive success among males. Most juvenile males dispersed to surrounding areas on maturity, whereas juvenile females stayed inside the area next to the mother’s territory. The main cause of mortality was traffic accidents. Males had a higher mortality rate (22 out of 41 males (54%) vs. 9 out of 43 females (21%)). During winter 2007/08 we identified 47 individuals, 41 of which originated from mating within the release area. This study demonstrates that noninvasive molecular methods can be used efficiently in post-release monitoring studies of elusive species to reveal a comprehensive picture of the state of the population.     

A sensitivity analysis to methodological variation in indicator-based urban sustainability assessment: a Quebec case study

Methodological factors are often acknowledged for their impact on the urban sustainability assessment outcomes. The significance of this impact, however, divides those who assign it great importance; to the point of compromising any attempt at sustainability benchmarking using indicators, from those who regard it as having a relatively limited role. In this paper, we aim to contribute to this debate by assessing how methodological choices could influence the variation in the outcomes of indicator-based urban sustainability benchmarking. The paper starts with a literature review outlining the evolution of the approaches adopted since the pioneering experiences in the ‘90s to show a convergence in indicators and data over time. Subsequently, by using the data of the 25 most populous cities in Quebec, we empirically analyse the sensitivity of the cities’ sustainability scores to 18 combinations of estimation techniques, and observe consistency within the outcomes while maintaining general patterns regardless of the approach used. The results suggest that methodological choices play a limited role in the urban sustainability assessment outcomes. Thus, other determinants beyond the evaluation methods are most likely involved and therefore should be a major focus in future research agendas.