Article

The effect of translocation and temporary captivity on wildlife rehabilitation success: An experimental study using European hedgehogs (Erinaceus europaeus)

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Abstract

Translocation is frequently used to return rehabilitated animals to the wild, and is an important tool for the population management of endangered species. Whilst experimental field manipulations are important in determining optimal rehabilitation and translocation strategies, they are rarely implemented in practice. We used an experimental approach to examine the effects of translocation on post-release survival and behaviour, and the impact of introductions on the recipient wild population, using the European hedgehog (Erinaceus europaeus), the most common mammal admitted to British wildlife hospitals. The post-release survival and behaviour of five groups were compared: three different translocation treatments, one wild population at the release sites and one control wild population away from the release sites. Individuals that were held in captivity prior to translocation had a better survival rate on release than individuals that were translocated with a minimum time spent in captivity. We suggest that temporary captivity improves chances of survival by allowing the build up of fat reserves and reducing manipulation stress suffered on release. No evidence was found for intra-specific competition between introduced individuals and the recipient wild hedgehog population.

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... Birds comprised 83.4% of animals, mammals the remainder (Table 1) (Fajardo et al. 2000), and separation between rescue and release locations (Molony et al. 2006). ...
... Only one study considered impacts of releasing opportunistically rescued animals on recipient population. Two populations of Western European hedgehog Erinaceus europaeus, one receiving rescued and rehabilitated animals and a separate control population, exhibited no differences in survival rate, nightly range size, distance travelled and proportion of night spent active, indicating absence of competition between released individuals and recipient population (Molony et al. 2006). We have not found any articles investigating impacts of animal release on population size, disease transmission, genetics or evolution. ...
... .Studies investigating release success for opportunistically rescued animals(Molony et al. 2006) have been few, but considered a broad range of factors. Post-release survival can be affected by going through rehabilitation(Wells et al. 2013), duration of rehabilitation period(Molony et al. 2006), whether animals are rescued as singles or in a group (e.g., dolphins exhibiting mass strandings;Wells et al. 2013), animal age(Griffith & Higgins 2012), receiving medical treatment(Griffith & Higgins 2012), training programs (e.g., owls 9 This article is protected by copyright. ...
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Vertebrate animals can be injured or threatened with injury through human activities, thus warranting their 'rescue'. Details of wildlife Rescue, Rehabilitation, Release, and associated Research (our 4 R's) are often recorded in large databases, resulting in a wealth of information. This information has huge research potential and can contribute to our understanding of animal biology, anthropogenic impacts on wildlife, and species conservation. However, such databases have been little used, few studies have evaluated factors influencing success of rehabilitation and/or release, recommended actions to conserve threatened species have rarely arisen, and direct benefits for species conservation are yet to be demonstrated. We therefore recommend additional research based on rescue, rehabilitation and release of animals, broader in scope than previously carried out, which would also maintain support from the general human community. This article is protected by copyright. All rights reserved.
... Survival and movement data from released hedgehogs can also provide valuable insights into the conservation of hedgehogs under rapid land use change and habitat degradation through agriculture, urban development, and climate change in Arabia ( ). Previous research concerning Richer, 2009 hedgehog release and/or translocation has been carried out only in temperate environments, especially in the UK ( ; Morris et al., 1992Reeve, 1998Molony et al., 2006Warwick et al., 2006 ; ; ) where the environment may not be as unforgiving as a desert. Release methods that have worked in temperate conditions may not work in hot arid environments. ...
... Even captive individuals Reeve, 1998 with little or no previous experience of life in the wild appear to quickly learn their way about, and interacted normally with each other and with wild conspeci cs ( ). fi Morris and Warwick, 1994 Although the average body weight of animals decreased signi cantly in 21 out of 24 animals during the rst week, their weights fi fi reached an asymptote and stabilized by the end of the third week (see Fig. 5), becoming more comparable to those of the wild population during the same season (Abu Baker et al., unpublished data). It is not surprising that body weights of hedgehogs in captivity were heavier than those of wild hedgehogs because of greater food availability and con ned space under captive conditions ( ; fi Suedmeyer, 1997Molony et al., 2006Abu Baker et al., 2016a ). Thus, the loss of weight following the release may simply be due to the di erence in living conditions ff between the wild and captivity. ...
... This is the rst study demonstrating the feasibility of releasing fi captive-born hedgehogs into the wild and providing data on their movement patterns and body weight changes. The results compare favorably with the survival rates of captive-bred and translocated European hedgehogs released in Europe and many carnivore species that were part of a reintroduction ( ; ; Morris et al., 1992Reeve, 1998Molony et al., 2006Warwick et al., 2006Jule et al., 2008 ; ; ...
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The survival, movement, and weight changes of 24 Ethiopian hedgehogs (Paraechinus aethiopicus) were monitored following their release from captivity. A total of 13 females and 11 males were released and radio-tracked for 2–4 weeks. 95% were alive after two weeks, and at least 54% were known to have survived throughout the study the remaining include 7 animals whose signals were lost after 3–24 days and 4 deaths after 3–24 days). The average daily distance travelled and distance between shelters ranged between 131.4–426.7 m and 103–1102 m, respectively. Distances were larger during the first week, for females than males, and for captive-born than wild-born. Twenty-one of the released hedgehogs showed significant weight loss during the monitoring periods; changes were between −25.0 and + 6.7 percent of starting body weight. Rates of weight loss were highest during the first week for both sexes and similar for wild-born and captive-born animals, but significantly greater for females. Stable bodyweights comparable to those of wild conspecifics were achieved after 23 days. This is the first study to evaluate the response of captive Ethiopian hedgehogs to release into the wild, which can inform future translocation and reintroduction efforts.
... The rehabilitation of sick or injured wildlife and their subsequent release back into the wild is considered an important tool in the conservation and management of endangered and threatened wildlife (Molony et al. 2006;Guy et al. 2013;Mullineaux 2014). However, welfare of the individual should be of primary concern throughout the rehabilitation process and the goal of rehabilitation should be to ensure that individuals are released in a physical and physiological condition that enables them to survive equally as well as wild individuals (Mullineaux 2014). ...
... Despite this, the reported success of rehabilitation varies considerably (Guy et al. 2013;Mullineaux 2014) with few studies conducted into the survival of released, rehabilitated animals (Molony et al. 2007). Given that, rehabilitated individuals are often considered to have a lower chance of survival compared to wild individuals as a result of reintroduction stress, impaired foraging ability and increased mortality risk (Molony et al. 2006) and altered ranging behaviour (Tolhurst et al. 2016), the lack of studies in this field needs addressing to provide evidence to inform rehabilitation practice. ...
... In Britain, at least 70,000 casualties are admitted to wildlife rescue centres annually (Grogan and Kelly 2013), with the European hedgehog Erinaceus europaeus being the most common mammal species admitted (Molony et al. 2006;Mullineaux 2014). An extended period of monitoring post-release is considered an essential part of the rehabilitation processes; however, this is not universally adopted (Guy et al. 2013). ...
Article
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The rehabilitation of sick or injured wildlife and their subsequent release back into the wild is considered important, not only for the welfare of the individual animal but also for the conservation and management of endangered and threatened wildlife. The European hedgehog Erinaceus europaeus has declined by 25% in Britain over the last decade and is the most common mammal admitted to wildlife rehabilitation centres in Britain, with a large proportion of individuals admitted to gain body weight overwinter prior to release in the spring. Consequently, many thousands of hedgehogs are housed overwinter which incurs significant costs for rehabilitation centres, and has potentially animal welfare issues, such as, stress in captivity, reintroduction stress, increased mortality risk and impaired or altered behaviour. To determine if releasing rehabilitated hedgehogs during autumn and winter had an effect on their survival, body weight or nesting behaviour, we compared these factors between 34 rehabilitated hedgehogs with 23 wild hedgehogs across five sites in England over four different winters. Overwinter survival was high for both wild and rehabilitated hedgehogs, with a significant decrease in survival across both groups when hedgehogs became active post hibernation in spring. We found no differences in the survival rates up to 150 days post release, in weight change, or nest use between wild- and winter-released rehabilitated hedgehogs. Our results suggest that under the correct conditions, rehabilitated hedgehogs can be released successfully during winter, therefore avoiding or reducing time in captivity.
... T he European hedgehog, Erinaceus europaeus, was classified as being of Least Concern when last reviewed in 2008 by the International Union for the Conservation of Nature (IUCN). 1 Recent studies in the UK, however, demonstrate a substantial decline. [2][3][4] Specific factors driving the decline in UK populations remain unclear, 5 although habitat conversion and fragmentation, predation, road traffic accidents, and injuries sustained in gardens or caused by pets have been identified as likely causes. 4,6 A considerable number of mortalities are due to natural causes, including parasitic burdening, as E. europaeus is host to a diverse range of endoparasites and ectoparasites. ...
... 4 Erinaceus europaeus is the mammal species most frequently admitted to wildlife hospitals across the UK, and is therefore a large source of information. 5 Ticks (Ixodes spp.) are one of the most common ectoparasites identified on E. europaeus; the nematodes Crenosoma striatum and Capillaria spp. are the most common endoparasites. ...
... The progress of rehabilitation in relation to initial parasitic burden also remains unreported in scientific literature. Because many E. europaeus are admitted to rescue centers across the UK, 5 an examination of the effects of parasites on living individuals and the effect of the composition of parasitic burden on the rehabilitation progress is needed to inform current practice. ...
Article
Erinaceus europaeus is experiencing population decline across the UK. The species is host to a variety of parasitic organisms. This study investigates and evaluates direct fecal smears as a diagnostic method for endoparasites. A number of Erinaceus europaeus (n = 47) were assessed on arrival at Prickles and Paws Hedgehog Rescue in Cornwall. Endoparasitic burden was determined via 10 direct fecal smears; ectoparasites were removed and counted. Minimum sample size required for representative burden estimate was determined. No significant difference was found in the mean number of eggs–larvae detected in 10 smears compared to two. No significant relationship was found between ectoparasites and endoparasites. Females had significantly greater burdens of Crenosoma striatum than males. This study provides new insight into gender bias in endoparasitic burdening and the relationship between endoparasitic and ectoparasitic burdening of rescued E. europaeus. It offers potential to influence husbandry protocols, welfare, and the success of rehabilitation, as well as increase efficiency andaccuracy of endoparasite diagnosis.
... Due to this medial presence, and their popularity and presence in gardens, they are often the center of attention when it comes to human-mediated rescue actions. Hedgehogs are frequently translocated and among one of the most abundant species found in wildlife shelters in western Europe [17]. Wildlife shelters rehabilitating hedgehogs can also be found across Austria (at least one in every federal province) [18]. ...
... The primary aim of these shelters lies in the successful rehabilitation and subsequent release of their temporary patients back into the wild. This, however, may result in (unintentional) translocation; if the individual's origin is unknown, a release at the original site is not possible or if individuals cannot individually be identified after their stay in the shelter [17,18]. It is also known that such release locations are often chosen because of their suitable habitat, while the actual origin of hedgehog individuals is rarely recorded by the animal shelters (in Austria). ...
... Various studies showed the capability of rehabilitated juvenile and adult hedgehogs to survive after their release [47,48]. Additionally, an improvement in the fitness of hedgehogs in Great Britain following temporary captivity was found [17]. The same study showed that rehabilitated and in turn released hedgehogs did not affect wild individuals through an increase in competition. ...
Article
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Hedgehogs are among the most abundant species to be found within wildlife shelters and after successful rehabilitation they are frequently translocated. The effects and potential impact of these translocations on gene flow within wild populations are largely unknown. In this study, different wild hedgehog populations were compared with artificially created “shelter populations”, with regard to their genetic diversity, in order to establish basic data for future inferences on the genetic impact of hedgehog translocations. Observed populations are located within central Europe, including the species Erinaceus europaeus and E. roumanicus. Shelters were mainly hosting one species; in one case, both species were present syntopically. Apart from one exception, the results did not show a higher genetic diversity within shelter populations, indicating that individuals did not originate from a wider geographical area than individuals grouped into one of the wild populations. Two shelters from Innsbruck hosted individuals that belonged to two potential clusters, as indicated in a distance analysis. When such a structure stems from the effects of landscape elements like large rivers, the shelter management-related translocations might lead to homogenization across the dispersal barrier.
... The rehabilitation of orphaned, sick or injured wildlife followed by their release back into the wild is an important aspect of the conservation of threatened wildlife [29,30]. However, when wild animals are placed in captivity, e.g. at a wildlife rehabilitation centre, they encounter a novel, confined and unpredictable environment, which often includes handling and close proximity to humans [31]. ...
... Previous research has investigated the post release survival and spatial behaviour of rehabilitated hedgehogs [30,[67][68][69][70][71][72][73], and some have included wild individuals for comparison [30,70,73] or described the survival of wild, translocated individuals [74]. However, few studies have directly compared the survival of rehabilitated and wild individuals, where both groups had been translocated [30]. ...
... Previous research has investigated the post release survival and spatial behaviour of rehabilitated hedgehogs [30,[67][68][69][70][71][72][73], and some have included wild individuals for comparison [30,70,73] or described the survival of wild, translocated individuals [74]. However, few studies have directly compared the survival of rehabilitated and wild individuals, where both groups had been translocated [30]. ...
Article
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Background The European population of hedgehogs ( Erinaceus europaeus ) is declining. It is therefore essential to optimise conservation initiatives such as the rehabilitation of sick, injured and orphaned hedgehogs. Wild animals placed in captivity may be prone to chronic stress, potentially causing negative health effects. Therefore, the effects of these rehabilitation efforts should consequently be evaluated. Furthermore, hand-raising orphaned hedgehogs is a laborious and costly task, and it is therefore relevant to document whether they have equal post release survival rates compared to their wild conspecifics. The objectives of this research were therefore to conduct an exploratory study of glucocorticoid levels in hedgehogs from different backgrounds and compare the post release survival of translocated, rehabilitated and wild, juvenile hedgehogs as well as the possible effect on survival of differences in shy or bold behaviour (personality) exhibited by individuals. Results We measured glucocorticoid levels in 43 wild-caught (n = 18) and rehabilitated (n = 25) hedgehogs and compared the post release survival and spatial behaviour of 18 translocated juvenile hedgehogs (eight hand-raised and ten wild) until hibernation. The possible effect on survival of differences in shy or bold behaviour (personality) exhibited by 17 juvenile individuals (seven hand-raised and ten wild) was also examined. Rehabilitated individuals and females had higher levels of faecal corticosterone metabolites compared to wild individuals and males, respectively. Rehabilitated individuals showed higher levels of saliva corticosterone than wild. The personality tests labelled 13 individuals as shy and 11 as bold. Post release survival was 57% for rehabilitated and 50% for wild individuals. Neither background nor personality affected post release survival. Home range measures were 3.54 and 4.85 ha. Mean dispersal length from the release sites was 217 ± 100 m. Conclusion The higher levels of corticosterone observed in rehabilitated compared to wild hedgehogs calls for consideration of the duration of admission to wildlife rehabilitation centres to reduce stress levels in the patients. Hand-raised juveniles appear to have the same prospects as wild, and personality does not seem to affect post release survival in hedgehogs, indicating that hand-raising of orphaned juvenile hedgehogs is a relevant contribution to the conservation of this species.
... Survival rates also vary between studies of E. europaeus and we must be careful about drawing conclusions from these comparisons as figures are presented from a range of habitats and methodologies. Translocated and released hedgehogs have a survival rate of between 40% and 77% after several weeks in the wild [47][48][49][50]. Survival of individuals in extant populations over short periods is higher, for example nearly 95% during an eight week study in urban habitats in the UK [49]. ...
... Translocated and released hedgehogs have a survival rate of between 40% and 77% after several weeks in the wild [47][48][49][50]. Survival of individuals in extant populations over short periods is higher, for example nearly 95% during an eight week study in urban habitats in the UK [49]. Reeve 1981 [28] found a survival rate of 62%, over one year including winter, however over two winters this was reduced to 37%. ...
Article
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Information on population characteristics of Paraechinusis is valuable for ensuring long term survival of populations, however, studies are currently lacking. Here we investigate the population dynamics of Ethiopian hedgehogs based on a capture-mark-recapture study in Qatar by fitting Jolly-Seber and Cormack-Jolly-Seber models. Over the 19 months of the study, we estimate a mean population of 60 hedgehogs, giving a density of 7 hedgehogs per km2 in our 8.5 km2 search area. The monthly abundance of hedgehogs decreased over the study and although survival was constant over the study period, with a mean monthly rate of 75%, there was a decline in the number of new entrants over time. We also studied these parameters over one year, excluding winter, and found that monthly estimates of juvenile and subadult survival decreased over time. We surmise that survival of juveniles may be a factor in the decrease in abundance and there may be implications for the persistence of this population, with anthropogenic influenced resources playing an important role. We caught between 91.3% and 100% of the estimated population at this site, indicating that our capture methodology was efficient. We conclude that the methodology used here is transferrable to other hedgehog species.
... No Brasil, mesmo considerando os altos recursos humanos e financeiros inerentes ao resgate e reabilitação dos animais (Magroski et al., 2017), o retorno da fauna apreendida ao seu habitat de origem tem sido a estratégia mais adotada pelos órgãos governamentais . Solturas mal-planejadas, contudo, são passíveis de causar diversos impactos ambientais, como a introdução de patógenos ou doenças (Cunningham, 1996;Jiménez e Cadena, 2004;Godoy e Matushima, 2010), mudanças nas interações ecológicas inter e intraespecíficas, como competição, predação, parasitismo e mutualismo (Jiménez e Cadena, 2004;Molony et al., 2006), e modificação na estrutura genética das populações como perda de adaptações locais e eliminação 19/195 da diferença genética entre populações (Moritz, 1999;. Por outro lado, se bem planejado e considerando questões como bem-estar, valor de conservação e custos, o retorno de animais apreendidos à natureza apresenta inúmeros benefícios: i) melhora o potencial de conservação das espécies ou populações; ii) permite que os espécimes voltem a cumprir seu papel biológico e ecológico; iii) promove valores de conservação locais por meio de programas de educação ou consciencialização pública; e, iv) faz uma forte declaração política/educacional sobre o destino dos espécimes apreendidos (e.g. ...
... However, if poorly planned, these releases into can cause several negative effects on the environment such as pathogens or diseases introduction (Cunningham, 1996;Jiménez and Cadena, 2004;, changes in the inter-and intraspecific ecological interactions such as 139/195 competition, predation, parasitism and mutualism (Jiménez and Cadena, 2004;Molony et al., 2006), and modification in the genetic structure of populations such as loss of local adaptations and elimination of genetic difference among populations (Moritz, 1999;. On the other hand, well-managed reintroduction that considers welfare issues, conservation value, and costs could improve the long-term conservation potential of species or populations. ...
Thesis
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O tráfico de animais silvestres, uma das atividades ilegais mais lucrativas e dispersas por todo o mudo, tem gerado inúmeras consequências socioambientais como perda de divisas, introdução de espécies exóticas, transmissão de doenças e alterações em processos ecológicos. Não obstante aos prejuízos causados por sua ilicitude, milhares de animais são apreendidos anualmente, requerendo das autoridades governamentais elevados custos técnico-operacionais para a sua adequada destinação. Nesta Tese de Doutorado, nós discutimos a temática do tráfico de animais silvestres sob um olhar amplo e atualizado, elucidando questões originadas na dissociação do conhecimento científico com a resolução de problemas ambientais, também conhecida como lacuna ciência-prática. Desta forma, no primeiro capítulo, sintetizamos os principais macrofatores relacionados à captura de animais silvestres para o tráfico, buscando apontar os mais relevantes para a retirada ilegal de aves no Brasil. Assim, nós demonstramos que a cobertura por vegetação nativa e a proximidade às áreas protegidas, em detrimento aos fatores socioeconômicos, foram os motivadores mais relevantes sob uma análise em ampla escala. No segundo capítulo, nós avaliamos como o comércio legal ou ilegal da biodiversidade influencia na introdução de espécies exóticas e alterações dos padrões biogeográficos das espécies sobrexplotadas. Deste modo, nós observamos que a região amazônica foi uma das áreas mais vulneráveis à invasão das espécies de aves mais traficadas no Brasil. No terceiro capítulo, compilamos os principais fatores responsáveis pelo insucesso da restauração populacional de aves, seja esta relacionada à reintrodução ou revigoramento populacional. Neste capítulo, nós destacamos que, controlando ou eliminando fatores como predação, movimentos de dispersão pós-soltura e doenças, as ações que visem o retorno dos animais à natureza tendem a ser mais bem-sucedidas. Por fim, no quarto capítulo, nós avaliamos se os municípios-fonte para o tráfico são, de fato, os melhores locais para promover o retorno da fauna apreendida à natureza tendo em vista os irremediáveis impactos das alterações do clima. Deste modo, por meio da modelagem de nicho ecológico e utilizando as unidades de conservação de proteção integral como grupo controle, nós demonstramos que áreas diferentes da origem dos espécimes podem apresentar condições mais favoráveis para manter suas populações em longo prazo. Em síntese, por meios destes quatro capítulos, nós acreditamos ter trazido importantes avanços não somente no âmbito acadêmico, pela promoção de uma abordagem inovadora de temas ecológicos relevantes, mas também reforçamos a necessidade de maior junção da teoria com a prática, buscando fornecer subsídios diretos a gestores e tomadores de decisão envolvidos na proteção e conservação da fauna traficada em todo o mundo.
... Animal rehabilitation is the practice of removing wild ani- mals that are injured, sick, orphaned or dislocated and caring for them until they can be returned to their natural habitat ( Molony et al., 2006;Wimberger, Downs & Boyes, 2010;Guy, Curnoe & Banks, 2013). Worldwide, the use of reha- bilitation as a conservation tool is growing, requiring resources such as time and funding (Molony et al., 2006;Guy et al., 2013). ...
... Animal rehabilitation is the practice of removing wild ani- mals that are injured, sick, orphaned or dislocated and caring for them until they can be returned to their natural habitat ( Molony et al., 2006;Wimberger, Downs & Boyes, 2010;Guy, Curnoe & Banks, 2013). Worldwide, the use of reha- bilitation as a conservation tool is growing, requiring resources such as time and funding (Molony et al., 2006;Guy et al., 2013). Although some species suffer high mortal- ity in temporary captivity (e.g. ...
Article
The use of wildlife rehabilitation for conservation is growing, but quantitative criteria are rarely used to guide whether and when to remove animals from the wild. Since 2006, large numbers of African penguin Spheniscus demersus chicks have been abandoned annually when adults enter moult with dependent young still in the nest. As part of conservation initiatives for this endangered species, these chicks were collected and hand reared to fledging age. Post-release survival has been well documented; in this study we develop models to predict survival of individuals during rehabilitation with the aim of improving hand-rearing success and guiding the use of scarce resources. For 1455 chicks abandoned between 2008 and 2013, we assessed whether a chick body condition index (BCI) could predict outcome (death or release) and time spent in rearing. In addition, for a subset of 173 chicks in 2012, we assessed whether BCI at admission influenced chick growth rates during rehabilitation and examined whether the use of additional structural measurements and sex provided additional power to predict outcome. Models predicted an 82.9% (95% confidence interval: 73.3–89.5%) release rate for chicks admitted with a BCI >0, the proposed guideline for removal from colonies. This fell below 50% for BCIs < −1.05; 66% of chicks were admitted with BCIs between these thresholds. Adding bill length to BCI improved the relative model fit, but in both cases only ~70% of rehabilitation outcomes were correctly predicted. Chicks that grew more quickly were more likely to be released and, for those that were released, had lower BCI at admission suggesting compensatory growth. Chicks were generally removed at an appropriate time to ensure successful hand-rearing. However, 32% were admitted in good condition, highlighting the importance of using adaptive management to guide wildlife rehabilitation and the allocation of conservation resources.
... The number of hedgehogs in Great Britain has been steadily declining over the last few decades (Hof 2009;Roos 2012;Wilson 2018). Additionally, hedgehogs are the most frequently admitted mammal to British Wildlife Rehabilitation Centres WRCs (Kirkwood 2003;Bullen 2002;Molony 2006), where they require care for a number of issues such as malnutrition, traumatic injury, disease, parasite burden and orphaning (Robinson and Routh 1999;Bunnell 2001;Stocker 2013); many of which are the result of human influence (Reeve and Huijser 1999). The care for hedgehogs in WRCs is time-consuming and expensive but has the end goal of rehabilitating them and releasing them healthy back into the wild (Stocker 2013;Mullineaux 2014, RSPCA). ...
... The care for hedgehogs in WRCs is time-consuming and expensive but has the end goal of rehabilitating them and releasing them healthy back into the wild (Stocker 2013;Mullineaux 2014, RSPCA). There has been some research into the post release success of hedgehogs suggesting that it is largely successful (Morris et al. 1994;Sainsbury et al 1996;Reeve 1998;Molony 2006;Warwick et al 2006;Yarnell et al 2019). Although there have been studies into rescue centres' admission data and mortality rates in previous decades (Molony 2007;Grogan 2013) and other countries (Martinez 2014), there has only been limited research on British centres for the past decade, and what there is limited geographically and in its numbers. ...
Article
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The hedgehog ( Erinaceus europaeus ) population is in decline in the UK and they are the most frequently admitted mammal to British Wildlife Rehabilitation Centres (WRCs). Whilst successful, UK rehabilitation is time-consuming and expensive and few large-scale studies into UK WRC admission and survival rates have been published in the last decade. This paper examines admission and survival trends in 19,577 hedgehogs admitted to Royal Society for the Prevention of Cruelty to Animals centres over a 13 year period (2005–2017) to gauge the state of Britain’s hedgehogs in WRCs and to gain indirect insight into the wild population. During the studied period, admissions more than doubled. Admission weights were greater in later than early litter juveniles. The survival improved 26% overall, and 33% in juveniles. Twenty two percent of animals died or were euthanased within 48 h of admission. Kaplan–Meier analysis gave survivor functions of 0.78 at 2 days, 0.66 at 10 days, 0.62 at 20 days, and 0.53 at 80 days. Survival was independent of admission weight in each age category. In particular, survival was greater in early litter juveniles than in adults or late litter juveniles; and across the breeding season diminished in juveniles and increased in adults. These data suggest factors impacting hedgehog survival have remained stable despite population decrease; that care methods have improved; and that late litters are more vulnerable than early. For WRCs this reaffirms that current methods are successful, but that further resources could be directed towards late litters.
... However, a successful treatment followed by releasing hedgehogs back to their natural habitat does not ensure their subsequent survival in the wild. According to Molony et al. [52], the ability of released individuals to adapt to novel sites is critical. Many hedgehogs cannot be returned to the area where they were found. ...
... The time the hedgehogs spent in the rescue center is related to the time needed for animals to achieve optimum condition and thus maximize their chances of survival [55]. According to Molony et al. [52], temporary captivity improves the chances of survival by allowing the build-up of fat reserves and reducing manipulation stress suffered on release. ...
Article
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The European hedgehog ( Erinaceus europaeus ) is a species found in abundance throughout Europe. Nevertheless, it has seen a decline in some regions. This study aimed to analyze trends in intake and outcomes for hedgehogs admitted into rescue centers in the Czech Republic. In the period from 2010 to 2019, 16,967 European hedgehogs were admitted in 34 rescue centers in the Czech Republic. Most hedgehogs were admitted in September (25.30%) and October (22.14%), the fewest in March (0.96%). Most admitted hedgehogs were hoglets (59.49%). The treatment was successful in 44.39% of admitted hedgehogs; those were subsequently released into the wild. On average, they stayed in rescue centers for 48.77 days (median of 30 days). Death or euthanasia was an outcome for 25.27% and 3.15% of admitted hedgehogs, respectively. Only 0.59% of the hedgehogs remained in captivity with a permanent handicap. The highest release rate was achieved in hedgehogs admitted after falls into pits and other openings (83.19%), whereas the least success was achieved in poisoned hedgehogs (13.21%). An increasing trend (rSp = 0.9273, p < 0.01) was found in the number of hedgehogs admitted to rescue centers during the monitored period. Furthermore, not all of them required human care. Given the fact that less than a half of the admitted hedgehogs could be released, raising public awareness of this issue could help to avoid unnecessary interventions (especially in hoglets).
... The International Wildlife Rehabilitation Council defines wildlife rehabilitation as the "managed process whereby a displaced, sick, injured or orphaned wild animal regains the health and skills required to function normally and live self-sufficiently". However, of those rehabilitated individuals who have a chance to be released into the wild, there is a low chance of survival post admission into clinical care, (Molony et al., 2006). Referring to that earlier in New South Wales between 1989 and 2018, 20% of koalas admitted into clinical care were released into the wild (Charalambous & Narayan, 2020), whereas in Queensland between 1997 and 2013, only 17% of koalas admitted into clinical care were released into the wild (Gonzalez-Astudillo et al., 2017). ...
... Factors that could affect survival in those individuals who have been released into the wild include handling stress (Monnett, 2000), pre-release conditioning such as identifying food and predators (Suarez et al., 2001), and the suitability of the release location (Monnett, 2000). However, there are few studies that monitor post-release success in wildlife (Molony et al., 2006). ...
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Koalas (Phascolarctos cinereus) are one of Australia's most charismatic native small marsupial species. Unfortunately, populations of koalas are rapidly declining throughout Australia and they continue to face increasing pressure from a changing ecosystem. Negative stimulants in the environment can elicit stress responses through activation of the hypothalamic-pituitary-adrenal (HPA) axis. Depending on the duration of the negative stimulant, the stress response can lead to either acute or chronic side effects, and is shown through the activation of the neuroendocrine stress system and the release of glucocorticoids (e.g., cortisol). Wild koalas entering clinical care face novel stressors that can be out of a wildlife carer's control. In this pilot study, we monitored physiological stress in three wild koalas at a wildlife rehabilitation centre in New South Wales, Australia. Acute and chronic stress was indexed non-invasively, with faecal samples taken to evaluate acute stress, and fur samples taken to evaluate chronic stress. Sampling occurred sporadically over four months, from the start of September 2018 to the end of December 2018. Results attempt to understand the stress response of koalas to negative stimulants in the environment by comparing faecal glucocorticoids on days where a known stressor was recorded with days where no known stressor was recorded. Furthermore, variations in faecal and fur glucocorticoids were compared between the three koalas in this study. To our knowledge, this is the first evidence of stress tracking of wild rescued koalas in a sanctuary. We suggest that further monitoring of baseline, acute and chronic stress will be needed to better understand how koalas respond to negative stimulants associated with clinical care.
... It is generally considered that the propensity to move, the distance moved, and the frequency of movement can be high just after release (Le Gouar et al. 2012). Studies have frequently reported animals dispersing away from the release site (Le Gouar et al. 2012), or having larger home ranges (Hester et al. 2008), but occasionally translocated animals have responded with reduced ranging behaviour (Molony et al. 2006). However, the release of animals into a novel environment is known to have a greater effect on stress than the release of animals back into their home area (Dickens et al. 2009). ...
... Wildlife rehabilitation is a common practice, motivated primarily by animal welfare concerns (Guy and Banks 2012). However, it is also a potentially valuable conservation tool if returned animals contribute to species' persistence (Molony et al. 2006; Saran et al. 2011) or population recovery after a catastrophic event (). There is growing recognition of the need to determine the success of rehabilitation practices, particularly the survival and reproduction of returned wildlife. ...
Article
The increasing fragmentation of fire-prone forests of Australia has made the remaining populations of koalas (Phascolarctos cinereus) more vulnerable to extinction. We examined the movement patterns of koalas in remnant forest of Port Stephens following a major wildfire. Each koala (n≤55) was monitored regularly by radio-tracking for up to 35 months. The movements of koalas showed a wide variation in patterns, from highly localised movements to long-range dispersal over 20km. Within the first 12 months, 35% of tracked koalas moved from their release location to new areas where they established home ranges. Daily movement distances of males (mean≤278.3m) was higher than for females (141.0m). Monthly displacement ranged from less than 10m to more than 5km, and was higher for koalas that subsequently died. Home ranges of males (95% kernel) were significantly larger than those of females (mean for males≤58.9±10.5ha; mean for females≤25.7±8.6ha), and this sex difference was also evident for core areas (50% kernel). There were no differences in the movement patterns or home-range sizes of rehabilitated koalas compared with wild koalas. This study has shown that resource depletion from wildfire is short term for koalas because their mobility allows rapid recolonisation of the burnt forest, and they can maintain home ranges within sites regenerating from fire. The reintroduction of rehabilitated koalas into burnt forest may also assist in the recovery of populations in fragmented and isolated habitat.
... Another option is to compare translocated animals to a resident population at the release area, which is presumably familiar with and well-adjusted to the surrounding habitat. Thus the resident population can provide good baseline data for comparing, for example, survival rates (Strum 2005, Molony et al. 2006, Frair et al. 2007, habitat choices (Ostro et al. 2000), and movement patterns (Moehrenschlager and MacDonald 2003, Molony et al. 2006, Rittenhouse et al. 2007). This could be valuable for long-lived species whose survival and reproductive success may take years to assess, and for situations that require timely decision making (Pinter-Wollman et al. 2009). ...
... Another option is to compare translocated animals to a resident population at the release area, which is presumably familiar with and well-adjusted to the surrounding habitat. Thus the resident population can provide good baseline data for comparing, for example, survival rates (Strum 2005, Molony et al. 2006, Frair et al. 2007, habitat choices (Ostro et al. 2000), and movement patterns (Moehrenschlager and MacDonald 2003, Molony et al. 2006, Rittenhouse et al. 2007). This could be valuable for long-lived species whose survival and reproductive success may take years to assess, and for situations that require timely decision making (Pinter-Wollman et al. 2009). ...
Article
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Evaluations of wildlife translocation can be traditional assessments of survival and reproductive success or can be expanded to include valuable but seldom used measures of behavior and physiology in reference to baseline data from a resident population. In Alberta, Canada where grizzly bears (Ursus arctos) are listed as a threatened species, there has been research on resident grizzly bear populations but limited follow-up of translocated individuals associated with management actions. We determined an outcome for 110 grizzly bear translocation events (77 failed events, 33 successful events) between 1974 and 2014. We used logistic regression to investigate the effects of individual bear characteristics, management strategies, and habitat factors on translocation success. A translocation event was successful if the bear did not require further management action and if the bear survived at least one year without homing. We also compared the home range size, habitat selection, and denning behavior of translocated bears to the resident population over time to assess the long-term effects of translocation. The odds of translocation success were higher if bears were moved early in the year and decreased by 47% for each unit increase in the level of mortality risk (based on road density, water, and edge features) at the release site. The odds of homing decreased substantially at translocation distances >100 km, but bears translocated outside the Bear Management Area (BMA) of capture had annual home ranges that were 3.25 times larger on average than resident bears. Translocated bears were initially selecting high quality habitat similar to areas used by resident bears, but this behavior appeared to decline after the first year of translocation. Den entry dates, den exit dates, and the denning period of translocated bears did not differ significantly from resident bears. Our findings can aid managers in making more informed decisions when considering translocation as a tool for managing human–bear conflict or supporting grizzly bear conservation efforts. © 2018 The Wildlife Society.
... Wildlife rehabilitation is defined as 'the managed process whereby a displaced, sick, injured or orphaned wild animal regains the health and skills it requires to function normally and live self-sufficiently' (Molony et al. 2006: p. 530). There are notable success stories of hand-reared or captive-bred animals being successfully reintroduced to the wild, often featuring wombats ( Saran et al. 2011) and Tasmanian devils (Rogers et al. 2016). ...
Article
The non-human animal deaths and injuries that result from collisions with motor vehicles are known colloquially as roadkill, and often lead to individuals from various taxa being orphaned. The complexities of multiple spatial and temporal variables in the available data on Australian roadkill and the scale of orphaning and injury make statistical analysis difficult. However, data that offer proxy measures of the roadkill problem suggest a conservative estimate of 4 million Australian mammalian roadkill per year. Also, Australian native mammals are mainly marsupial, so female casualties can have surviving young in their pouches, producing an estimated 560 000 orphans per year. A conservative estimate is that up to 50 000 of these are rescued, rehabilitated and released by volunteer wildlife carers. These roadkill-associated orphans are in addition to those produced by other anthropogenic and natural events and the injured adult animals in the care of volunteers. In accepting total responsibility for rescued animals, wildlife carers face many demands. Their knowledge base can require days of initial instruction with the need for continual updates, and their physical abilities and personal health can be tested by sleepless nights, demanding manual tasks and zoonoses. This review article explores the impact of this commitment and conservatively estimates carers' financial input to raise one joey at approximately $2000 a year, and their time input at 1000 h, equating to $31 000 per year, applying a dollar value of $31 per hour. It categorises relevant types of grief associated with hand-rearing orphans and rehabilitating injured animals, and suggests that wildlife carers most likely experience many types of grief but are also susceptible to burn-out through compassion fatigue. A perceived lack of understanding, empathy and appreciation for their work by government can add to the stressors they face. Volunteering is declining in Australia at 1% per year, social capital is eroding and the human population is aging, while the number of injured and orphaned animals is increasing. Wildlife carers are a strategic national asset, and they need to be acknowledged and supported if their health and the public service they provide is not to be compromised.
... However, there is ambivalent evidence regarding the survival rates of translocated animals (Fontúrbel and Simonetti 2011). Published results vary greatly; some studies have reported improved survival rates following translocation (Molony et al. 2006), whereas others reported ~100% mortality rates (Fontúrbel and Simonetti 2011) or increased aggressiveness among translocated individuals (Athreya et al. 2011). We propose that a quantitative review is needed to assess patterns in the outcome of conflict translocations, and to determine the sources of variance in animal survival. ...
Article
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Wildlife management balances conservation goals with meeting societal objectives. It incorporates scientific disciplines such as ecology, animal behaviour, geography, and sociology to determine management practices and make policy recommendations. Two major areas of contemporary management are conservation (protecting animals in at risk environments) and conflict management (mitigating human-animal conflict). Translocation, the targeted movement of animals to a new location, is a method that can be used for conservation or conflict management. When dealing with conflict animals, translocation offers several advantages over culling. It can allow for the survival of the animal, a particular concern with threatened species, and has relatively low impact on its non-problem conspecifics. However, there is ambivalent evidence regarding the effectiveness of translocations. We conducted a series of categorical and continuous model meta-analyses to assess the effect of translocation on the survival of terrestrial vertebrates. For all cases combined, translocation reduced mean percent survival relative to rates observed in reference populations. Overall, animals moved for conflict purposes had significantly reduced mean percent survival, while animals moved for conservation purposes did not. Large mammal mean survival is significantly reduced by translocation, but small mammals did not experience this reduction. Although translocation has been implemented for several decades, improvements over time have only been made in conservation efforts. Based on our review, we discuss opportunities and challenges in the management of problem animals through translocation.
... Although hedgehog populations have been relatively well studied in urban areas (e.g. 4,[53][54][55][56], studies in rural landscapes have typically been conducted either at a local level (e.g. 22,37,38,57,58 ), such that their results may not be representative of larger geographic scales, or at a large-spatial scale that makes it difficult to clearly identify underlying biological and/or anthropogenic influences (e.g. ...
Article
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Agricultural landscapes have become increasingly intensively managed resulting in population declines across a broad range of taxa, including insectivores such as the hedgehog (Erinaceus europaeus). Hedgehog declines have also been attributed to an increase in the abundance of badgers (Meles meles), an intra-guild predator. The status of hedgehogs across the rural landscape at large spatial scales is, however, unknown. In this study, we used footprint tracking tunnels to conduct the first national survey of rural hedgehog populations in England and Wales. Single and two-species occupancy modelling was used to quantify hedgehog occupancy in relation to habitat and predator covariates. Hedgehog occupancy was low (22% nationally), and significantly negatively related to badger sett density and positively related to the built environment. Hedgehogs were also absent from 71% of sites that had no badger setts, indicating that large areas of the rural landscape are not occupied by hedgehogs. Our results provide the first field based national survey of hedgehogs, providing a robust baseline for future monitoring. Furthermore, the combined effects of increasing badger abundance and intensive agriculture may have provided a perfect storm for hedgehogs in rural Britain, leading to worryingly low levels of occupancy over large spatial scales.
... Sentinel surveillance of hedgehogs that had signs of disease has resulted in a powerful and inexpensive public health monitoring tool to follow invasion of A. cantonensis lungworms in Mallorca. Hedgehogs are ubiquitous in Europe, and they have been reported as the most common mammal admitted to wildlife hospitals in Europe, where their clinical signs can be monitored closely (21,22). Despite the proven utility of this strategy, sentinel surveillance is often underused for detecting emerging pathogens (23). ...
Article
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Neural angiostrongyliasis is an emerging zoonosis caused by the rat lungworm, Angiostrongylus cantonensis. In humans, infection with this nematode often results in eosinophilic meningitis and other severe disorders of the central nervous system. Europe was deemed a nonendemic region until 2018, when A. cantonensis worms were detected on the Mediterranean island of Mallorca, Spain, a tourism hotspot. Since that time, a sentinel surveillance system and a molecular approach have been used to follow the invasion path of the rat lungworm on the island. A. cantonensis worms have been found in animals from 8 locations on the island over 3 consecutive years. Our preliminary results show a recognizable pattern of clinical signs in infected hedgehogs and a single mitochondrial haplotype circulating in Mallorca. We present strong evidence confirming that the rat lungworm has successfully established and colonized an island in Europe and discuss observations and possible strategies for its early detection across continental Europe.
... Social interactions between released in-dividuals and local populations of conspecifics are not frequently considered in translocation programs, although they may affect the fitness and the settlement of the individuals: in released African elephants, social association with conspecifics improved the individuals' acclimation to novel environments, and the released individuals could integrate into the existing local populations (Pinter-Wollman et al. 2009). Similarly, no evidence of competition was observed between released and resident European hedgehogs (Molony et al. 2006). Furthermore, in some bird species, it has been observed that local populations facilitate the settlement of reintroduced conspecifics (Ahlering and Faaborg 2006). ...
Article
European rabbit translocation is an extended practice in Spain, France, and Portugal, for both conservation and hunting purposes. Some of these translocations are carried out with the aim of reinforcing existing rabbit populations. In these cases, some of the new rabbits are released into warrens already occupied by resident conspecifics. This could have a negative impact upon both the released and the resident individuals owing to the “dear enemy” effect and the territoriality of the resident rabbits. In this study, we evaluated the effect of rabbit release into occupied warrens, in small areas populated by low-density resident rabbit populations. We observed negative effects at two different levels: the number of active entrances per recipient warren and the number of active warrens per reinforced plot, in addition to a general lack of increase in rabbit abundance in the area and, therefore, the failure of the reinforcement actions. Our results strongly suggest that the release of European rabbits into warrens occupied by resident rabbits is contraindicated if the objective is to recover rabbit populations in the area.
... The radiotags used were 0.87-1.84% of the hedgehog's body mass, in the range of values known to have no effect on DEE in small mammals (Berteaux et al., 1996a). Hedgehogs were marked with six 1 cm pieces of coloured heat-shrink tubing, which were glued over spines in a patch on the rear (Molony et al., 2006). As DEE may vary with reproductive state in small mammals (Fletcher et al., 2012;Key and Ross, 1999;Poppitt et al., 1993Poppitt et al., , 1994, we measured testes length, or checked for signs of lactation and pregnancy. ...
Article
Full-text available
Failure to balance daily energy expenditure (DEE) with energy intake can have animpact onsurvival and reproduction, and therefore onthe persistence of populations. Here we study the DEE of the European hedgehog (Erinaceus europaeus), which is declining in the UK. We hypothesise that there is a gradient of suitable habitat for hedgehogs in rural areas, which is a result of fewer food resources, a higher risk from predation by badgers (Meles meles) and colder ambient temperatures, as distance to the nearest building increases. We used the doubly labelled water method to obtain 44 measurements of DEE from hedgehogs on four predominately arable sites, to determine the energetic costs associated with proximity to buildings, on sites with and without badgers. The mean±s.e.m. DEE was 508.9±34.8 kJ day⁻¹. DEE increased the further a hedgehog was from buildings during the study, possibly as they ranged larger distances on arable land, supporting the hypothesis that hedgehogs select villages owing to the lower energy demands in comparison to arable farmland. Hedgehogs had an approximately 30% lower DEE on sites with badgers. We speculate that on badger-occupied sites, hedgehogs may restrict movement and foraging in response to a threat from predation and thus have reduced DEE. Therefore, hedgehogs may also seek refuge in villages where the perceived threat of predation is lower and foraging is unrestricted. In a broader context, we demonstrate that individual differences in DEE can aid in understanding habitat selection in a patchily distributed species.
... Florida manatees held in captivity for longer periods may need additional time and multiple opportunities to acclimate to life in the wild as suggested by previous assessments (Adimey et al., 2009;Normande et al., 2015). Other studies involving carnivores and hedgehogs have also shown that extended time in captivity can promote the suppression of instinctual behaviors (Brill & Friedl, 1993;Sainsbury et al., 1996;Molony et al., 2006;Jule et al., 2008) and increase susceptibility to stressrelated medical issues, resulting in a reduced fertility and reproductive lifespan (Hermes et al., 2004;Jule et al., 2008). The data reported herein show the high percentage of successful outcomes for manatees held in captivity for < 5 y vs those held in captivity for > 5 y. ...
Article
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The rescue, rehabilitation, and release of Florida manatees (Trichechus manatus latirostris) into the wild has occurred since 1974; however, a comprehensive evaluation of the outcomes of the releases has never been conducted. Herein, we examined data for 136 Florida manatees that were rehabilitated and released with telemetry tags between 1988 and 2013 to determine release outcome of each individual as either success (acclimation) or failure after at least 1 y. Ten predictor variables were statistically evaluated for potential relationships to release outcome. To assess the contribution of each predictor variable to release outcome, each variable was tested for significance in univariate analyses. Manatees born in captivity experienced poor success after release (14%), whereas the overall success of wild-born individuals was higher (72%). When compared with other variables in our dataset, number of days in captivity was the strongest predictor for determining success. Manatees rescued as calves and held in captivity for more than 5 y had a high likelihood of failure, while subadults and adults had a high likelihood of success, regardless of the amount of time spent in captivity. Ensuring the success of individual manatees after release is critical for evaluating the contribution of the manatee rehabilitation program to the growth of the wild population.
... Leighton et al., 2008;Griffiths et al., 2010), but is also true for mammals, e.g. hedgehogs (Erinaceus europaeus) (Molony et al., 2006) and polecats (Mustela putorius) (Kelly et al., 2010). Whilst assessing short-term survival is clearly an important objective, other measures of animal welfare are required to truly evaluate the rehabilitation process. ...
Article
Temporary removal of wild animals from a resident territory has the potential to markedly impact subsequent ranging behaviour, and may negatively affect post-release welfare and survival. Admission of sick or injured wildlife into temporary captivity (termed ‘rehabilitation’) is a common practice in the UK. However, post-release monitoring of rehabilitated animals is unusual or restricted to recording survival rates over limited time periods. As part of a wider study of urban fox behaviour, we employed an experimental approach to compare the ranging behaviour of seven rehabilitated and 13 wild-caught ‘control’ urban red foxes using GPS tracking. Foxes were tracked over a two-year period for an average of 48 nights, and seasonal and sex-related effects were controlled for via inclusion in statistical models. Three of the five movement parameters we investigated were irregular for the rehabilitated animals, relative to controls. These were: reduced likelihood of establishing a stable home range (42.9/57.1% of rehabilitated foxes versus 84.6% of controls); larger home ranges (Kruskal Wallis test, χ2 = 7.517, df = 1, p < 0.01); and further distance travelled from release point, as measured by overlap between initial and final home ranges (Linear regression, F1,12 = 4.755, df = 1, P < 0.05). Females moved greater distances than males overall, and foxes from both groups travelled further in spring, and delayed home range establishment in summer. However, these results were skewed by the movements of two apparently cooperatively breeding wild-caught vixens. Our data provide evidence of territorial displacement of rehabilitated foxes on release. We discuss the welfare implications of this finding.
... In conclusion, as far as we are aware, this is the first study to compare temperament traits of wild-caught individuals with survival and change in body condition after translocation. Studies on common species of least conservation concern can be used to deliver findings that are then transferable to rare species, which are generally not suited to experimental manipulation (Molony et al. 2006). Results of this study therefore have important implications for the successful translocation of rare or endangered species, where screening translocation candidates could greatly increase the success of future translocation programs. ...
Article
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Translocation is an important conservation management tool. However, not all individuals are equally suited to translocation, and temperament traits (e.g., boldness, reactivity, exploration, sociability, and aggression) are likely to influence survival in a new environment. A few empirical studies have examined the consequences of personality differences on captive-bred translocated animals, but this has not been done for wild-caught animals. We compared behavioral responses to trapping, processing, holding, and release for 56 wild common brushtail possums (Trichosurus vulpecula). Twenty individuals were captured twice, once to attach radio-tracking collars, the second time (2 weeks later) for the translocation. Consistency of behavioral responses was compared between capture events and radio-tracking allowed estimates of pretranslocation home range, rest site selection, and foraging behavior. Survivors (n = 10 survivors, 5 months later) were individuals showing the most fear or emotional reactivity during holding (less likely to have slept, eaten, defecated, or nested) and those that had the smallest home ranges and selected the safest den sites in their original habitat. Conversely, the greatest increase in body mass was recorded for individuals that had demonstrated “unsafe” behavior in their original habitat. To our knowledge, this is the first time this type of behavioral screening during handling and holding prior to release as part of a translocation has been undertaken. These methods have broad applicability for screening potential translocation candidates and are easily translated to a range of threatened and vulnerable animal species.
... However, other explanations cannot be discounted. Different species respond in very different ways to time spent in captivity (Molony et al. 2006;Jule et al. 2008), as well as to conditions in the captive environment (Biggins et al. 1999;Field et al. 2007) and at the release site (Goossens et al. 2005). We discuss some of the factors influencing wombats in more detail below. ...
Article
Full-text available
Wildlife rehabilitation seeks to return healthy animals back to their natural habitat with good survival prospects,and hence contribute to the persistence of their populations. However, the effectiveness of rehabilitation remains largelyundocumented, and its utility as a conservation tool is unclear. In this paper, we document the rehabilitation successof a large, herbivorous marsupial, the common wombat (Vombatus ursinus), and use the findings as a case study toevaluate the contribution that rehabilitation can make to wildlife conservation. Using a database of 54 orphaned wombatsmonitored for up to eight years, we found that 81.5% of young survived to release and, of those, 77.3% were alivein the wild by the end of the study. Survival during rehabilitation was greater for larger, older animals, but influencedalso by problems during care, reaction to human contact following weaning and, in particular, the responses ofindividuals to treatment. No factors associated with rescue condition, rehabilitation or release affected survival of animalsonce returned to the wild, suggesting that wombats were not disadvantaged by their progression through rehabilitation.We provide brief recommendations to improve rehabilitation success for wombats. We conclude that rehabilitation isan under-recognized but potentially valuable conservation tool, and suggest that it is timely to consider its contributionto wildlife management more generally.
... La rehabilitación ha sido definida como el proceso indispensable para incrementar el éxito de la supervivencia de los individuos una vez liberados; al mismo tiempo, los procesos de rehabilitación son importantes en general para mejorar las condiciones de bienestar de animales cautivos (Molony et al., 2006;Sánchez-López, 2008;Guy, Curnoe y Banks, 2013). Por lo tanto, el enriquecimiento ambiental debe estar fundamentado en el comportamiento de las especies en vida silvestre (Chamove, 1989;Shepherdson, Mellen y Hutchins, 1998;Sánchez-López, 2008). ...
... Chilvers et al. (2015) looked at the effects of rehabilitation on diving and foraging in Little Blue Penguins (Eudyptula minor) and found that rehabilitated penguins consumed similar diets and survived and reproduced as effectively as non-rehabilitated penguins. Rehabilitated European Hedgehogs (Erinaceus europaeus) showed high degrees of survival post-release, so long as they were not translocated from their original home ranges; even then, those in captivity for >1 month showed higher rates of survival than those released shortly after capture ( Molony et al. 2006). Together, these studies indicate that rehabilitation may be a viable conservation strategy. ...
... We are currently living in the era of human impact known as the 'Anthropocene', where considerable habitat degradation and wildlife population declines have restricted many species to entirely captive populations (Lees and Wilcken, 2009). The management of wildlife has also increased the number of individuals being processed through rehabilitation centers and requiring veterinary interventions (Molony et al., 2006;Grogan and Kelly, 2013). These centers are incapable of ensuring the survival of every individual that comes into their care and thus often have access to relatively fresh carcasses. ...
Article
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In order to effectively conserve species, we must understand the structure and function of integral mechanisms at all levels of organismal organisation, from intracellular biochemistry to whole animal ecophysiology. The accuracy of biochemical analyses depend on the quality and integrity of the samples analysed. It is believed that tissue samples collected immediately postmortem provide the most reliable depiction of the living animal. Yet, euthanasia of threatened or protected species for the collection of tissue presents a number of ethical complications. Polyunsaturated fatty acids (PUFA) are essential to the cardiovascular system of all animals and the structure of PUFA can be degraded by peroxidation, potentially modifying the fatty acid composition of the tissue over postmortem time. Here, we assessed the composition of PUFA in cardiac tissue of bats (Carollia perspicillata) over the course of 12-h postmortem. We show that PUFA are resistant to naturally occurring postmortem degradation in heart tissue, with no difference in the overall composition of fatty acids across all time classes (0, 3, 6 or 12-h postmortem). Our results suggest that carcasses that would otherwise be discarded may actually be viable for the assessment of fatty acid composition in a number of tissues. We hope to spur further investigations into the viability of carcasses for other biochemical analyses as they may be an untapped resource available to biologists. Cite as: Currie SE, Mène-Saffrané L, Fasel NJ (2019) Valuable carcasses: postmortem preservation of fatty acid composition in heart tissue.
... Survival post-release [74,[82][83][84][85] Sufficient fat reserves or heavier mass on release ab Weight loss in migratory birds b Loss of wild behaviours such as predator avoidance and disruption of social development due to human habituation ab , although habituation was not related to survival in deer a [90] Hunting and wild behaviour training Survival to release [78] Construction of a pre-release flight tunnel for raptors b [78] N/A Survival post-release [91,[94][95][96][97] Provision of suitable hunting training b ...
Article
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Millions of native animals around the world are rescued and rehabilitated each year by wildlife rehabilitators. Triage and rehabilitation protocols need to be robust and evidence-based, with outcomes consistently recorded, to promote animal welfare and better understand predictors of wildlife survival. We conducted a global systematic review and meta-analysis of 112 articles that reported survival rates of native mammals and birds during rehabilitation and after release to determine intrinsic and extrinsic factors associated with their survival. We assessed survival during rehabilitation and in the short- and long-term post-release, with the hypothesis that survival will vary as a function of species body size, diel activity pattern, trophic level and study location (region of the world). We aimed to determine the direction of effect of these factors on survival to assist in decision-making during triage and rehabilitation. Results showed that mammals and birds were equally likely to survive all stages of rehabilitation, and survival rates varied between locations. Birds in North America had the poorest survival rates post-release, particularly long-term, as did diurnal and carnivorous birds in the short-term post-release. Anthropogenic factors such as motor vehicle collisions and domestic or feral animal attack contributed to morbidity and post-release mortality in 45% (168 of 369) of instances. The reasons for rescue and associated severity of diagnosis were commonly reported to affect the likelihood of survival to release, but factors affecting survival were often species-specific, including bodyweight, age, and characteristics of the release location. Therefore, evidence-based, species-specific, and context-specific protocols need to be developed to ensure wildlife survival is maximised during rehabilitation and post-release. Such protocols are critical for enabling rapid, efficient rescue programs for wildlife following natural disasters and extreme weather events which are escalating globally, in part due to climate change.
... The staff of Wildlife Rescue Centers (hereafter, WRCs) in urban areas is usually trained to record species, age and sex of each individual brought by the public, i.e. representing an invaluable source of wildlife data, particularly in urban environments (Ancillotto et al. 2013;Shine and Koenig 2001). Animals rescued by the public may thus provide researchers reliable data on their ecology, distribution and epidemiology, otherwise difficult to obtain (Reeve and Huijser 1999;Molony et al. 2006;Aaziz et al. 2015;Ancillotto et al. 2018). Therefore, WRCs may act as a reliable citizen-science based method to estimate both local changes in species phenology and population trends. ...
Article
Full-text available
Monitoring population trends of alien species is pivotal to design effective management plans to preserve native biodiversity, particularly urban areas, where most populations of alien birds are established. Urban wildlife rescue centers, with personnel trained to record species, age and sex of each individual brought by the public, may represent a reliable citizen-science based method to estimate both local changes in alien species phenology and population trends. In this work, we analysed records of monk and ring-necked parakeets by comparing rescue records in the urban area of Rome from the last 15 years. We also tested whether breeding phenology of alien parakeets showed any changes since the start of the invasion processes. We recorded a strong correlation between the number of rescued parakeets and their population trends, thus confirming the importance of wildlife rescue centers in monitoring populations of alien species in urban areas. We also observed a shift in the breeding phenology of these parakeet species. The hatching peak for ring-necked parakeet occurred in early spring, in line with previous studies on the reproduction of this species, but with a slight increase in the number of months with evidence of breeding in the last years. As to the monk parakeet, our findings support the expansion of its reproductive season between 2006 and 2020 in Rome, with chicks currently being observed for seven months a year. Therefore, data collected through wildlife rescue centers may help improving models of population growth of alien species established in urban areas.
... The foraging area of the European hedgehog usually extends over a radius of 200-300 m around the nest, but it can also cover distances of several kilometers, with a considerable risk of being killed by vehicles or dying of unnatural causes [3][4][5][6][7]. As further proof of the close contact between hedgehogs and humans, this species is one of the most hospitalized mammal species in wildlife rescue centers in Italy [8] and other European countries as well [9][10][11][12][13][14][15]. ...
Article
Full-text available
The European hedgehog is a synanthropic mammal, widely distributed in Europe. This species usually inhabits the edges of deciduous or mixed woods, but it is also very common in private gardens and public parks. Despite its popularity and frequency of contacts both with humans and with wild and domestic animals, few studies have examined the endoparasitic fauna of the hedgehog in Italy. In the present study, endoparasites of naturally deceased hedgehogs (n = 40) from central Italy (Latium and Tuscany regions) were investigated, along with concurrent gross and histopathological lesions. The most prevalent identified endoparasites were Crenosoma striatum (45%), Capillaria erinacei (42.5%) and Brachylaemus erinacei (22.5%), in accordance with previous reports from hedgehogs in southern Italy. In few subjects, Physaloptera clausa, Acanthocephalans and Cystoisospora rastegaeivae coccidia were also identified. The infection by the lungworm C. striatum was found to be significantly associated (p < 0.01) with bronchial hyperplasia and peribronchiolitis upon histopathological examination. Awareness of the most common parasitic infections in the hedgehog and of their effects on the health of these animals is extremely important, especially in wildlife rescue centers, where European hedgehog represents the most frequently hospitalized mammal species.
... Rautio et al. [45] also reported road mortality as the most common cause of hedgehog mortality in the wild in Finland. The time spent at a rescue center may be beneficial for injured or diseased hedgehogs [46]. Natural patterns of behaviour need to be preserved in juvenile European hedgehogs reared at rescue centers although the time spent in the rescue center does not appear to have a negative impact on natural patterns of behaviour [21]. ...
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This study aimed to assess the numbers of juvenile European hedgehogs admitted to rescue centers in the Czech Republic from the viewpoint of their weight on admission, the reason for their admission, and the success rate of their release back into the wild. The results of our study show varying levels of success in the rearing of hedgehogs admitted at different ages (weights) and a varying period required for their rehabilitation. The greatest chance of release was seen in hedgehogs with a weight on the admission of 500–599 g (64.22% released) and 400–499 g (63.31% released). In contrast, the smallest number of young hedgehogs successfully rehabilitated and released was seen in hoglets weighing 200–299 g (35.24% released) on admission, which corresponds to the weight of hedgehogs at the time of weaning. Time spent at a rescue center may pose an undesirable threat to the lives of animals in some categories. Hedgehogs weighing up to 99 g on admission spent the longest period time at rescue centers (a median of 48 days), while hedgehogs weighing 500–599 g on admission spent the shortest time (a median of 7 days). The majority of hedgehogs in the lowest weight categories were admitted due to their inability to survive on their own. A large percentage of hedgehogs of greater weight, in contrast, were juvenile hedgehogs brought to rescue centers needlessly. The percentage of released animals did not exceed 65%, however, even for entirely independent categories of older juveniles. From this perspective, the fact that hedgehogs are often brought to rescue centers in the belief that they are not self-sufficient young, though they are actually juvenile or even adult individuals that do not require human care, can be considered a significant finding.
... Stress associated with captivity and poor health status may contribute to low survivorship and release success (Molony et al. 2006;Vogelnest 2008;Dickens et al. 2009). Acute and chronic stress is well documented in captive wildlife, as is the relationship between the physiological presentation of stress, and the welfare of animals housed in captive environments (Narayan et al. 2018). ...
... Wildlife rehabilitation is the multidisciplinary professional practice that involves displaced, sick, injured, or orphaned animals, which are taken into human care in order to regain health and skills required to survive in the wild (Molony et al. 2006; South African Wildlife Rehabilitators Association [SAWRA] 2009). This includes weaning of human dependency and contact, and the active reinforcement of natural behaviors that can help individuals survive in their natural habitat once released. ...
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There is a current global biodiversity loss at a rate 100 to 1000 times greater than the rate of natural extinction. Human activity, specifically human population growth and the necessary actions to sustain them, has led to habitat destruction , the rise of invasive species, climate change, and over exploitation of natural resources. In South Africa, an increasing number of nonhuman primates have entered into rehabilitation centers due to animal-human conflicts. The high accumulation of these primates has led to an increase in the need for group formation and releases at rehabilitation centers. Although the International Union for Conservation of Nature (IUCN) has published generic guidelines for the release of nonhuman primates, it recommends species-specific guidelines be published for optimal release success. Additionally, they emphasize the importance of following best practice management approaches to maximize conservation efforts and individual welfare of displaced species, while also aiming to provide guidance on the best practice approaches. To date, there are only a few published species-specific rehabilitation and release protocols for primates. We, therefore, created species-specific guidelines for the rehabilitation of chacma baboons (Papio ursinus) for reinforcement. The proposed guidelines are based on psychological well-being, social and individual behaviors, and the ecology of chacma baboons (Papio ursinus) for rehabilitation, release, and post-release assessments. Our guidelines include seven distinct steps: arrival, conspecific resocialization, housing, training , and preparation, pre-release assessment, release-site selection, release, and post-release assessment. We provide detailed information and examples of each step based on the protocols from the Riverside Wildlife Rehabilitation Centre (Riverside), a rehabilitation center in the Limpopo province of South Africa that has had successful rehabilitation and release projects for chacma baboons, among other primates. Since rehabilitation centers are limited by factors such as location and resources, this is meant to be a "best practice" model for this specific baboon species. The goal of these guidelines is to help assist future rehabilitation and releases, as well as provide a foundation to those who wish to modify the guidelines to create other species-specific rehabilitation steps.
... Conservation scientists typically focus their efforts on protection at the level of populations, species, and ecosystems, using tool sets such as population translocations and threat mitigation. Where wildlife rehabilitation and release efforts are represented in wildlife ecological and conservation research, studies have focused on evaluating rehabilitation methods (Molony, Dowding, Baker, Cuthill, & Harris, 2006), or on identifying potential pitfalls, such as the inconsistent application of protocols or the inadvertent transmission of disease through relocation of rehabilitated individuals (Deem, Karesh, & Weisman, 2001). Wildlife rehabilitation has also been portrayed as an indefensible use of resources that should be directed instead towards in situ biodiversity conservation and maintenance of landscape connectivity (Albrecht 1998). ...
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Wildlife rehabilitation is the treatment and subsequent release of injured wildlife. Wildlife rehabilitation benefits individual animals receiving care, but also supports Conservation Medicine approaches by providing opportunities to monitor wildlife health, contaminant loads, and disease prevalence. However, it is typically considered to have negligible effects on population growth, and has not traditionally been acknowledged as an effective tool for wildlife conservation. To explore whether rehabilitation and release could directly support population recovery in some cases (i.e. increase population growth rates), we considered five case study species along a spectrum of life-history strategies (Raccoon, Painted Turtle, Blanding’s Turtle, Snapping Turtle, and Little Brown Bat). We simulated populations over 200 years, while varying two parameters: 1) the rate of severe injury (0, 1, 2, or 5% of the population); and 2) how many of these injured animals are successfully rehabilitated (0, 10, 25, or 50%). The effect of the rehabilitation scenarios was largest when additive severe injury rates were highest (5%). Species that were most sensitive to increased adult injury rates (turtles and bats) also exhibited the greatest population-level responses to rehabilitation and release interventions. We conclude that wildlife rehabilitation can support in situ recovery and help stabilize declining populations when 1) injury is an ongoing source of high additive mortality, 2) the target population is small, 3) the species exhibits a K-selected life-history strategy, 4) rehabilitation can be combined with other interventions, including in situ threat mitigations, and 5) rehabilitation efforts do not jeopardize or limit in situ conservation interventions.
... These events are not fully quantified at present, but our interviews with personnel from rescue facilities confirmed that they are a regular occurrence, some estimates suggesting several hundred per year. Such rescue related translocations have also been observed in other studies [60,69,70]. ...
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We use the European hedgehog (Erinaceus europaeus), a mammal with limited mobility, as a model species to study whether the structural matrix of the urban environment has an influence on population genetic structure of such species in the city of Berlin (Germany). Using ten established microsatellite loci we genotyped 143 hedgehogs from numerous sites throughout Berlin. Inclusion of all individuals in the cluster analysis yielded three genetic clusters, likely reflecting spatial associations of kin (larger family groups, known as gamodemes). To examine the potential bias in the cluster analysis caused by closely related individuals, we determined all pairwise relationships and excluded close relatives before repeating the cluster analysis. For this data subset (N = 65) both clustering algorithms applied (Structure, Baps) indicated the presence of a single genetic cluster. These results suggest that the high proportion of green patches in the city of Berlin provides numerous steppingstone habitats potentially linking local subpopulations. Alternatively, translocation of individuals across the city by hedgehog rescue facilities may also explain the existence of only a single cluster. We therefore propose that information about management activities such as releases by animal rescue centres should include location data (as exactly as possible) regarding both the collection and the release site, which can then be used in population genetic studies.
... La rehabilitación ha sido definida como el proceso indispensable para incrementar el éxito de la supervivencia de los individuos una vez liberados; al mismo tiempo, los procesos de rehabilitación son importantes en general para mejorar las condiciones de bienestar de animales cautivos (Molony et al., 2006;Sánchez-López, 2008;Guy, Curnoe y Banks, 2013). Por lo tanto, el enriquecimiento ambiental debe estar fundamentado en el comportamiento de las especies en vida silvestre (Chamove, 1989;Shepherdson, Mellen y Hutchins, 1998;Sánchez-López, 2008). ...
... In these five years, 69% of the alive admitted hedgehogs could be returned to the wild (65 hedgehogs/year on average), similar percentage to that reported by Bunnell (2001). Although successful release of wildlife does not necessary equate to successful rehabilitation (Sharp, 1996), in the case of hedgehogs we could think that most of the animals released were successfully rehabilitated, firstly because both adult and naïve juvenile hedgehogs cope well with release (Morris et al., 1993;Morris and Warwick, 1994;Morris, 1997), and secondly because all the rehabilitated individuals were monitored in an outdoor acclimatisation facility for a period of time prior the final release, providing a reasonable indication of their survival capability in the wild (Bunnell, 2002;Molony et al., 2006). The use of photo-trapping infrared cameras with nocturnal video function was very useful to assess health status, motor skills or behavior of hedgehogs at the outdoor enclosure during this last stage of the rehabilitation process. ...
Article
We studied hedgehog admissions to the three Wildlife Rehabilitation Centers of the Valencian Community (eastern Spain) over a five years period (2009-2013). A total of 490 hedgehogs were admitted: 84% corresponded to Western European hedgehogs and 16% to Algerian hedgehogs. A bimodal distribution of the admissions was observed along the year, with highest number of admissions during summer and a much smaller peak on winter, largely due to the arrival of young hedgehogs. Main reasons for admission were casual encounters (41%) and orphaned young (19%). In total, 69% of the individuals that arrive alive to the centers could be released successfully to the wild, with better recovery indices for animals accidentally found, previously held in captivity and orphaned young; and worst indices for parasitized hedgehogs, affected by infections and by road casualties. Finally, involving the general public in the rehabilitation process (e.g., returning animals to the wild, collaborating with "soft-releases") proved to be very productive, for both environmental awareness purposes and for the rehabilitated animals.
... The hedgehog is the mammal species most frequently admitted to wildlife rehabilitation centers in Great Britain. 10 Hygiene precautions are recommended as a routine (e.g., wearing disposable, protective gloves during handling and washing hands afterwards), particularly for hedgehog carers who frequently handle hedgehogs. Immunocompromised people and pregnant women should take particular care when in contact with hedgehogs. ...
Article
Listeria monocytogenes is a ubiquitous environmental bacterium that causes disease in a wide range of species. Infection with this pathogen is most frequently diagnosed in ruminant livestock, but is also known to infect people and occasionally wildlife. Postmortem examinations of Western European hedgehogs (Erinaceus europaeus) in Great Britain (2011–2017) identified five (5/266, 2%, 95% confidence interval: 0.8–4.3%) animals with L. monocytogenes infection. The L. monocytogenes isolates comprised three serogroup 1/2a and two serogroup 4 from three multilocus sequence types (2, 37, and 121), all of which were different by single-nucleotide polymorphism analysis, indicating they were distinct and epidemiologically unrelated. These findings are consistent with hedgehogs contracting sporadic infection from the environment, perhaps through eating soil-dwelling invertebrates. Examination of data from scanning surveillance programs focused on other British wildlife species indicates that the hedgehog is one of the wildlife species from which L. monocytogenes has been most frequently identified to date in Great Britain. However, further studies of multiple taxa with comparable sampling efforts are required to assess the relative frequency of L. monocytogenes infection in different wildlife species. The bacterium was isolated from extraintestinal sites in multiple hedgehogs, which may indicate septicemia. However, histological examination was limited and could not discriminate subclinical infection from disease (i.e., listeriosis). Although L. monocytogenes is a zoonotic pathogen, disease in people is typically contracted from the ingestion of contaminated foods. The risk to immunocompetent people of contracting listeriosis from hedgehogs is considered very low to negligible.
... Captivity may even have positive effects in some cases. For example, hedgehogs were more likely to survive a translocation event if they were held in captivity for greater than 1 month compared to those held <6 days (Molony et al., 2006). ...
Article
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Wild animals are brought into captivity for many reasons-conservation, research, agriculture and the exotic pet trade.While the physical needs of animals are met in captivity, the conditions of confinement and exposure to humans can result in physiological stress. The stress response consists of the suite of hormonal and physiological reactions to help an animal survive potentially harmful stimuli. The adrenomedullary response results in increased heart rate and muscle tone (among other effects); elevated glucocorticoid (GC) hormones help to direct resources towards immediate survival. While these responses are adaptive, overexposure to stress can cause physiological problems, such asweight loss, changes to the immune systemand decreased reproductive capacity. Many people whowork with wild animals in captivity assume that they will eventually adjust to their new circumstances. However, captivitymay have long-term or permanent impacts on physiology if the stress response is chronically activated. We reviewed the literature on the effects of introduction to captivity in wild-caught individuals on the physiological systems impacted by stress, particularly weight changes, GC regulation, adrenomedullary regulation and the immune and reproductive systems. This paper did not review studies on captive-born animals. Adjustment to captivity has been reported for some physiological systems in some species. However, for many species, permanent alterations to physiology may occur with captivity. For example, captive animals may have elevated GCs and/or reduced reproductive capacity compared to free-living animals even after months in captivity. Full adjustment to captivity may occur only in some species, and may be dependent on time of year or other variables.We discuss some of the methods that can be used to reduce chronic captivity stress.
... However, activity, exploration and aggressiveness are also energetically costly, so temperament has a significant influence on metabolic rate and energy consumption (Careau et al. 2008). Temperament thus affects energy balance and body mass gain, and can be a useful indicator of post-translocation fitness (Molony et al. 2006). ...
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Context Temperament can affect an individual’s fitness and survival if it also influences behaviours associated with predator avoidance, interactions with conspecifics, refuge selection and/or foraging. Furthermore, temperament can determine an individual’s response to novel stimuli and environmental challenges, such as those experienced through translocation. Increasing our understanding of the effect of temperament on post-translocation fitness is thus necessary for improving translocation outcomes. Aims The aim was to test whether differences in an individual’s behaviour or physiology could help predict body mass changes post-translocation in the woylie (brush-tailed bettong, Bettongia penicillata ogilbyi). In the absence of predation (due to release into a predator-free exclosure), body mass was used as a proxy for an individual’s success in securing resources in the new habitat, and therefore fitness. Methods Forty woylies were translocated from two predator-free exclosures to a larger exclosure, all in Western Australia. Behavioural and physiological measures were recorded during trapping, processing, holding, and release, and again at re-capture ~100 days post-release. Key results Translocated woylies generally increased in body mass post-translocation. This suggests that, in the absence of predation, the selected candidates were able to cope with the stress of translocation and possessed the behavioural plasticity to successfully find resources and adapt to a novel environment. The strongest predictors of body mass gain were sex, heart rate lability and escape behaviour when released (a convoluted escape path). Conclusions There was no significant difference in body mass between males and females pre-translocation but females showed greater mass gain post-translocation than did males, which could reflect greater investment in reproduction (all females had pouch young). Heart rate lability and escape behaviour are likely to reflect reactivity or fearfulness, a significant temperament trait in the context of translocation success. Implications Behavioural measures that can be easily incorporated into the translocation process – without increasing stress or affecting welfare of individuals – may hold promise for predicting the fate of translocated animals.
... In many source-countries for trafficking, even after considering the great human and monetary resources inherent in the rescue and rehabilitation of these specimens (Magroski, Pessoa, Lucena, Loures-Ribeiro, & de Araújo, 2017), the return of seized animals to the wild has been the most widely adopted procedure by government agencies (Destro et al., 2012). If poorly planned, however, this strategy can cause several negative | 3243 DESTRO ET al. effects on the environment such as pathogen or disease introduction (Cunningham, 1996;Godoy & Matushima, 2010;Jiménez & Cadena, 2004), changes in the inter-and intraspecific ecological interactions such as competition, predation, parasitism and mutualism (Jiménez & Cadena, 2004;Molony, Doowding, Baker, Cuthill, & Harris, 2006) and modification of the genetic structure of populations such as loss of local adaptations and elimination of genetic differences among populations (Champagnon, Elmbergd, Guillemaina, Gauthier-Clercb, & Lebretonc, 2012;Moritz, 1999). ...
Article
Regardless of the economic, social and environmental impacts caused by wild animal trafficking worldwide, the suitable destination of seized specimens is one of the main challenges faced by environmental managers and authorities. In Brazil, returning seized animals to the wild has been the most frequent path in population restoration programs, and has been carried out, as a priority, in areas where the animals were captured. However, in addition to the difficulty in identifying the locations of illegal captures, little scientific knowledge is available on the future viability of the source‐areas to global climate change. Thus, the current work aims to evaluate the impacts of climate change on the main source‐municipalities for animal trafficking in Brazil, referred to herein as source‐areas. For this, using ecological niche modeling, the environmental suitability of the source‐areas for illegal animal captures was evaluated in two scenarios at two differ time horizons: optimistic (RCP 26) and a pessimistic (RCP 85) emission scenarios in both 2050 and 2070 projections. Moreover, the source‐areas were compared with the Brazilian Federal protected areas, used here as the control group. According to the results, Brazilian source‐municipalities are not always the best option for maintaining the most seized species in the future simulations, and, therefore, seem not be the best option for projects that aim for the return of these animals to the wild. In this sense, despite the genetic and ecological issues inherent in translocation projects, our results suggest that population restoration programs for seized species need to be rethought, and furthermore other suitable areas could be considered for truly ensuring the survival and maintenance of overexploited populations in the long‐term. This article is protected by copyright. All rights reserved.
... If these are to be met, it should be mandated that all animals be examined by a veterinarian, qualified in wildlife medicine, before release. Undertaking behavioural assessments that could lead to either euthanasia or the inappropriate release of an animal requires considerable expertise and facilities and the need for a thorough knowledge of the species' wild behaviour [106]. The Australian regulations concerning the release of rehabilitated wildlife seem to assume that a veterinarian or experienced wildlife carer has these competences. ...
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The Australian constitution does not mention native animals. Responsibility for animal welfare is largely retained by the states and territories via a fragmented, complex, contradictory, inconsistent system of regulatory management. The problem this creates for volunteers undertaking the rescue and rehabilitation of native animals is complex. Capturing and rehabilitating wild animals goes against regulations. In most jurisdictions, it is illegal to microchip, band, or mark an animal, making it almost impossible to monitor their survival. A minimum of 50,000 rehabilitated native animals are released back to the wild each year, with few checks afterwards to see how well or if they are surviving. Whilst it can be appropriate to rehabilitate and release injured native animals back to the wild, there may be moral, ethical, and practical reasons for not releasing hand-reared orphan native animals. With no reliable method of identification, no instructions on how to get animals ready for release or see if they are suitable, and little post-release checking, the practice of placing hand-reared native animals into the wild, and the regulatory framework enabling it, should be reviewed. This article examines the evolution, and explains the consequences, of decentralised regulation on wildlife carers and rehabilitating animals. It recommends that the practice of placing hand-reared native animals into the wild, and the regulatory framework that provides for it, should be reviewed.
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The impacts of hedgehog (Erinaceus europaeus) Salmonella infection on public health and on animal welfare and conservation are unknown. We isolated Salmonella Enteritidis multi-locus sequence-type (ST)183 from 46/170 (27%) hedgehog carcasses (27 S. Enteritidis phage type (PT)11, 18 of a novel PT66 biotype and one with co-infection of these PTs) and from 6/208 (3%) hedgehog faecal samples (4 PT11, 2 PT66) from across Great Britain, 2012-2015. Whole genome phylogenetic analysis of the hedgehog isolates and ST183 from people in England and Wales found that PT11 and PT66 form two divergent clades. Hedgehog and human isolates were interspersed throughout the phylogeny indicating that infections in both species originate from a common population. PT11 was recovered from hedgehogs across England and Scotland, consistent with endemic infection. PT66 was isolated from Scotland only, possibly indicating a recent emergence event. People infected with ST183 were four times more likely to be aged 0-4 years than people infected by the more common ST11 S. Enteritidis. Evidence for human ST183 infection being non-foodborne included stronger correlation between geographic and genetic distance, and significantly increased likelihood of infection in rural areas, than for ST11. These results are consistent with hedgehogs acting as a source of zoonotic infection.
Article
Background: Hedgehogs ( Erinaceus europaeus ) are widespread throughout mainland Britain, often inhabiting parks and gardens in built-up areas. They are popular with the public, frequently coming top in polls of Britain’s favourite wild mammal. They are also the most common species of wildlife casualty encountered in veterinary practice. Aim of the article: This article describes the principles of hedgehog care while at the veterinary practice, and the treatment of some of the most common problems.
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Patient outcomes for hedgehog (Erinaceus europaeus) casualties are not limited to release versus euthanasia; some hedgehogs have conditions that do not preclude their ability to survive in captivity with human intervention. This research explored the welfare implications and ethical issues of keeping disabled hedgehogs in permanent captivity. Currently, there is very little in the literature and the subject is highly emotive and controversial. A questionnaire was used to assess welfare and these data contrasted with the normal behaviors, environment, and diet of free-living hedgehogs. The most convincing argument for keeping wild animals in captivity is species conservation; however, hedgehogs are not currently listed as endangered. Sixty-six datasets were obtained, representing 194 hedgehogs kept in permanent captivity. Results were mixed, i.e., many respondents providing suitable habitat features (for example, grass and soil 83.3% of respondents, shrubs and/or hedges 69.7% of respondents) observing “positive” behaviors such as foraging for natural foods (69.7% of respondents), and observing appropriate behavioral responses to humans; and some areas for concern, i.e., habitat size (22.7% of respondents reported habitats <10m²), presence of badgers (only 48.5% of respondents reported no badgers in the area), evidence of aggressive behavior (22.7% of respondents had observed non-food-related aggression between hedgehogs) and seven hedgehogs having sustained bite wounds whilst in captivity. The authors are cautious about drawing any definitive conclusions from this research, though it would appear that some of the hedgehogs in the survey had welfare comparable to their free-living counterparts.
Article
Background: Dermatophytosis caused by Trichophyton erinacei is a common scaling and crusting skin disease affecting European hedgehogs (Erinaceus europaeus) admitted to wildlife rescue centres. The application of topical therapy can be challenging because wild hedgehogs are subject to stress and often roll into a ball when handled. Systemic antifungal therapy is more convenient but has not been evaluated in this species. Hypothesis/objectives: To compare the efficacy of oral itraconazole versus oral terbinafine for the treatment of dermatophytosis affecting hedgehogs. Animals: A treatment trial was undertaken in a wildlife hospital involving 165 hedgehogs with naturally occurring dermatophytosis. Methods: Animals were randomly divided into two groups and treated with either itraconazole or terbinafine orally for 28 days. The therapeutic efficacy was evaluated after 14 and 28 days by mycological culture and clinical dermatological lesion scores. Results: Both drugs were well tolerated and clinically effective. After 14 and 28 days of treatment, the respective mycological cure rate was 36.6% and 65.9% for the itraconazole-treated group and 92.8% and 98.8% for the terbinafine-treated group. Conclusion and clinical importance: Itraconazole and terbinafine were both effective for the treatment of dermatophytosis affecting hedgehogs; however, terbinafine was more effective.
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Poaching is the primary threat to the survival of rhinoceros’ populations. One frequent consequence of poaching is the creation of orphan calves. If found, orphans are taken into captivity for rehabilitation and subsequent release. However, rehabilitation practices can influence their behavior and welfare, potentially compromising their post-release adaptation and survival. In this study, the effects of hands-off and hands-on rehabilitation methods on the behavior, welfare, and adaptation potential of orphaned white rhinoceros (Certatotherium simum simum) were compared. To achieve these aims, 12 behavioral, one physiological, and four physical indicators of welfare and adaptation potential were measured non-invasively on 25 orphaned rhino at two rehabilitation facilities in South Africa. Results indicated that although orphan welfare was not compromised under either rehabilitation method, the hands-off cohort showed fewer indicators of poor welfare and more indicators of good welfare. Regarding adaptation potential, hands-off rehabilitated rhino showed the species’ natural response to humans, and alert and defense behaviors were part of their behavioral repertoire. The hands-on cohort displayed fewer social interactions than the hands-off cohort, showed habituation to humans, and seldom expressed alert or defense behaviors, which could potentially compromise their survival and social integration after release. Post-release studies are required to confirm whether fitness is compromised in hands-on rehabilitated rhino. Until then, we suggest to minimize anthropogenic exposure during rehabilitation in order to maximize welfare and retain crucial behaviors for post-release adaptation and survival.
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Seals that survived their first year were on average 2% and 4% heavier at birth and at weaning than the "non-survivors". First year survival rates calculated for weaners over 135 kg weaning masses showed these weaners had higher survival rates than those less than 95 kg at weaning (71.55% and 54.15% respectively). Heavy weaners had greater fat reserves than light weaners and gained relatively more mass during lactation. Size, and therefore condition at weaning, influences first year survival.
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Many long-distance passerine migrants arrive with more fat stores than necessary to have reached their northerly breeding grounds. Researchers have argued for adaptive advantages associated with arriving with ‘surplus’ migratory fat, including increased breeding performance and insurance against adverse weather, and reduced food resources during the days following arrival. The objectives of this work were to document fat stores in American redstarts Setophaga ruticilla arriving to breed in northern Michigan and to test predictions associated with the hypothesis that arrival fat serves an insurance role. Results suggest that redstarts arrived in northern Michigan with fat stores sufficient to have continued migrating an additional distance greater than 1000 km. Significant yearly variation in arrival fat corresponded in part with environmental conditions measured at the breeding grounds. Birds arrived with the most fat in the year with the coolest temperatures and the lowest food abundance at the time of arrival to the site. Further, an inverse relationship between arrival fat and arrival day in males indicated that early arrivals carried more fat than later arrivals. Birds that arrived early faced cooler temperatures and lower densities of terrestrial invertebrates, and arrival fat may have provided a mechanism to overcome poor early season foraging conditions. However, our results are not entirely consistent with the hypothesis that arrival fat serves only as insurance. Arrival fat appeared important even during the most benign year of this study. Further, evidence suggests that females may have derived more benefit from arrival fat than males. These results highlight the connection between phases of a bird's annual cycle. Migrants that do well en route, arrive at breeding grounds in better condition, which may contribute to survival and reproductive success.
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The use of captive breeding in species recovery has grown enormously in recent years, but without a concurrent growth in appreciation of its limitations. Problems with (1) establishing self-sufficient captive populations, (2) poor success in reintroductions, (3) high costs, (4) domestication, (5) preemption of other recovery techniques, (6) disease outbreaks, and (7) maintaining administrative continuity have all been significant. The technique has often been invoked prematurely and should not normally be employed before a careful field evaluation of costs and benefits of all conservation alternatives has been accomplished and a determination made that captive breeding is essential for species survival. Merely demonstrating that a species' population is declining or has fallen below what may be a minimum viable size does not constitute enough analysis to justify captive breeding as a recovery measure. Captive breeding should be viewed as a last resort in species recovery and not a prophylactic or long-term solution because of the inexorable genetic and phenotypic changes that occur in captive environments. Captive breeding can play a crucial role in recovery of some species for which effective alternatives are unavailable in the short term. However, it should not displace habitat and ecosystem protection nor should it be invoked in the absence of comprehensive efforts to maintain or restore populations in wild habitats. Zoological institutions with captive breeding programs should operate under carefully defined conditions of disease prevention and genetic/behavioral management. More important, these institutions should help preserve biodiversity through their capacities for public education, professional training, research, and support of in situ conservation efforts.
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The demography of red squirrels Sciurus vulgaris removed from three different source areas and reintroduced between February 1987 and January 1988 in an urban park near Antwerp, Belgium was monitored for six years. Animals that were used to human presence had a higher initial survival than those not accustomed to human disturbance. Contrary to our predictions, woodland structure at the removal site did not affect a squirrel's settlement success, and post-release survival of subadults was not higher than that of adults. Only three (33%) introduced males, and five (50%) females survived to produce offspring. Reproductive rate was density-dependent and tended to increase with food abundance (tree seed crop of beech and oak). Consequently, population growth was high the first three years (low density) and decreased after 1990 (high density), when both adult and post-breeding densities (0·8–0·9 squirrels/ha) remained stable, suggesting the reintroduced population had reached its equilibrium density. We discuss some guidelines to increase the success of red squirrel reintroduction projects.
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We report the results of eight years of post-release monitoring of 37 wild-born, captive chimpanzees released into the Conkouati-Douli National Park, Republic of Congo. Overall survival was high, with 23 (62%) individuals remaining in the release zone, and only 5 (14%) confirmed dead. Released females regularly interacted with wild chimpanzees. Several females appeared to have integrated into wild groups for extended periods of time, and four released females gave birth to a total of five offspring. However, encounters with wild chimpanzees were a major cause of mortality in released males, and 40–50% of released males would have died without veterinary intervention. These sex differences are in accordance with knowledge of chimpanzee behavioural ecology. Our results demonstrate that wild-born, captive chimpanzees can be released into the wild successfully, under certain specific conditions. Most importantly, careful planning and preparation is critical at all stages; a suitable release area must be identified; potential risks to existing wild populations, including the possibility of disease transmission, must be minimised; and post-release monitoring is essential. Adolescent females are the most suitable candidates for release, as they appear to be able to integrate successfully into wild communities. However, males should not be released where wild chimpanzees occur, as they are likely to be attacked and killed. Release into the wild addresses the welfare of certain individual animals, although it clearly cannot address the fate of all captive, wild-born chimpanzees. Knowledge of how to successfully release chimpanzees into the wild also has both current and potential future benefits for the conservation of wild chimpanzee populations.
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Potential competitors that eat each other can engender patterns of spatial segregation similar to those produced by competition, and distinguishable only by field manipulation. This paper reports the results of a perturbation experiment to test the factors responsible for small-scale discontinuities in the distribution of a common insectivore. Populations of hedgehogs (Erinaceus europaeus) were monitored following their introductions into an area where they had been absent, and into a neighbouring area where they were known to persist. The two sites had a similar availability of preferred habitat, and the growth rates of introduced hedgehogs were similar. The density of badgers (Meles meles), larger members of the same guild, appears to produce differences in mortality and dispersal, which returned the populations close to their original levels within 2 months of the transplant.
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The low survival rate of Angel Island deer Odocoileus hemionus columbianus during 1 yr following release and reports of similar results for other relocated deer make it difficult to justify relocation on the grounds that it is humane. -from Authors
Article
Direct recoveries for Canada goose (Branta canadensis interior) goslings from the portion of the Southern James Bay Population (SJBP) on Akimiski Island, Nunavut, Canada, have declined markedly since 1987. We suspected that poor gosling nutrition, due to limited food resources on brood-rearing areas, was causing low survival. Consequently, we measured body size and condition of 2,893 unfledged goslings during late July and early August, 1994-1996. Based on 128 recoveries of dead birds during hunting seasons and 69 recaptures during summer on Akimiski Island, we estimated the separate influences of gosling size and condition on subsequent probabilities of recovery by hunters and survival. Estimated survival probabilities were 0.025, 0.051, and 0.147, and reporting probabilities were 0.0026, 0.0051, and 0.0142 for 1994-1996, respectively. Annual variation in both probabilities was related to size and condition of goslings, which were largest and in the best condition in 1996, followed by 1995, and then 1994. Estimates of slopes suggested that relatively small increases in both body size and condition resulted in increased survival and reporting probabilities. Unlike previous waterfowl research, our results showed that the largest goslings, and those in the best condition, were the most likely to be shot. We suggest that goslings in poor condition died on Akimiski Island before they fledged. We conclude that food availability was limiting recruitment, and predict that harvest restrictions on SJBP Canada geese will not result in an increase in the segment of the population that nests on Akimiski Island.
Article
This paper reports the results of a field experiment to identify factors regulating local variations in population sizes of a common insectivore. A low density population of hedgehogs Erinaceus europaeus was artificially increased in numbers while simultaneously a high density population was reduced. Subsequent dispersal, mortality and natality were monitored in complete censuses of the total populations, and compared to a control population of transplanted hedgehogs at unchanged density. Predation on hedgehogs was principally by badgers Meles meles which forage for substantially similar foods to hedgehogs, and was significantly higher in the expanded population during the first 2 wk after transplant than in the control, which nevertheless suffered a high overall mortality. Dispersal of male hedgehogs in particular from the expanded population contributed to reducing the density close to its original level within 1 month of transplant, after which the population remained relatively stable for a further 2 months of monitoring. Surviving hedgehogs at this site maintained closer proximity to residential buildings. which were avoided by badgers, than those at the control site, rates of weight gain by males were also superior to those in the control population. The artificially reduced population in an urban area containing no badgers was partially replenished within 1 month. through a decreased loss rate and an increased gain rate, initially of adults and later in the year of juveniles born after the transplant. The hedgehogs here showed seasonal variation in dispersion between fields, which were associated with the breeding cycle and the distribution of earthworm prey. Hedgehogs utilized mown grass fields in relation to the availability of earthworms Lumbricus spp., which was itself dependent on the age of fields. The study demonstrates that predation can influence the abundance of hedgehogs as well as their distribution in a heterogeneous environment. Residential and urban patches of land appear to represent a niche largely free from badger activity, where hedgehog populations maintain a high equilibrium density despite predation by domestic dogs which can contribute to a rapid population turn-over.
Article
Thirteen over wintered juvenile hedgehogs (six male, seven female) were released in an area of farm land and gardens on Jersey, Channel Islands. Six (three of each sex) were originally from the same area, the rest came from other parts of the island. They were radio-tracked and monitored regularly for 6 weeks to investigate survival and especially whether 'site-native' animals and those from elsewhere differed in respect of their propensity to disperse widely following release. All animals survived at least 4 weeks and 10 were known to be alive after 6 weeks. The fate of the others is unknown, but there is no reason to believe that any of them suffered an early death.Male hedgehogs used new nests more frequently than females. All remained within 400m of the release point for at least a month, some were still within 200m 6 weeks post-release. Five hedgehogs dispersed, travelling at least 400m from the release point. Four of these were males, including one recaptured 5.2km away. Dispersal seemed to be more related to sex than origin. All animals lost weight initially, but most stabilized after 2–3 weeks; proportionately more weight was lost by larger animals. None was seen to use supplementary food put out for them, despite weight losses, and no aggressive interactions with wild conspecifics were noted. Despite all the animals being naïve juveniles, with little or no previous experience of life in the wild, none were killed by road traffic. Positive conclusions from previous studies concerning the success and welfare implications of releasing hedgehogs after care in captivity are confirmed.
Article
The release of animals from captivity frequently leads to a period of erratic movement behaviour which is thought to expose the animal to a high risk of mortality. Twenty-six faxes which had been reared at a wildlife hospital or captive-bred, were radio-collared when nearly full-grown and released without site acclimation. Immediately after release there was an erratic phase of behaviour, during which the foxes travelled widely and movement parameters were markedly elevated. For those faxes which survived, a second phase was entered after an average of 17.2 days, during which one small area only was used, and movement parameters were much reduced. In a second study, nine faxes were released following site acclimation in a pre-release pen; this process postponed but did not eliminate the phase of high movement activity.This pattern of movement was compared with the dispersal behaviour of wild-reared foxes. It was concluded that released foxes, despite being proficient in other aspects of behaviour, were moving and behaving in a markedly abnormal manner and this resulted in a high death rate. The results are used to discuss methods of improving rehabilitation techniques.
Article
We report on the efficacy of body weight change as a measure of trapping and handling stress in two species of wild small mammal: bank voles (Clethrionomys glareolus) and wood mice (Apodemus sylvaticus). We tested two hypotheses: (1) that weight change after capture and handling is related to the intensity of the trapping and handling regime, and (2) that weight change after an intensive handling regime is related to an individual's current pattern of energy expenditure. Trapped wood mice that were subjected to intensive handling (intensive stressor) lost more weight than did animals that were handled minimally (less intensive stressor), but this was not the case for bank voles. Patterns and factors related to body weight change in response to intensive handling also differed between the two species: heavier and non-breeding bank voles were more likely to lose weight, but this was not true for wood mice, and none of the factors we measured was found to affect weight loss in this species. Our results were broadly consistent with the predictions of the biological cost hypothesis. We discuss the limitations and benefits of weight loss as a measure of stress.
Article
Many juvenile hedgehogs (Erinaceus europaeus) are 'rehabilitated' with little or no previous experience of life in the wild. A study is described in which twelve such animals were monitored after release in Devon. They quickly learned their way about, built nests and found them again, and interacted normally with each other and with wild conspecifics. While several showed significant weight loss, this represented only the excess accumulated in captivity. Deaths caused by a predator (badger) and motor cars suggest that captives destined for release should not be allowed to become tame and unwary. However, deaths are to be expected in natural circumstances and at least one third of these animals survived beyond the nine-week study, despite having no previous experience of life in the wild. This supports the belief that, although deaths are to be expected, rehabilitating hedgehogs (even naïve juveniles) is possible and worthwhile.
Article
The fate of rescued hedgehogs (Erinaceus europaeus) released back to the wild has now been the subject of several follow-up studies. Although subject to various hazards, released hedgehogs have clearly shown essential 'life-skills '. However, all previous studies have involved releases into hedgehog-rich areas and the observed long-range (≥500m) dispersal movements shown by some subjects, of up to 5km, may be a consequence of local intraspecific competition. This study has reduced a number of potentially confounding subject variables and provides follow-up data on 12 age-matched female hedgehogs with similar histories. A main group (n = 10) was released into a rural woodland area (Surrey, UK) of low natural hedgehog density, and radio-tracked for up to 108 days. A pilot release of two animals in an urban area with an established hedgehog population also took place (tracked for 109 and 131 days respectively). Most of the main group dispersed (up to 3km) from the release site; the two animals in the urban site did not. These data, taken with those from previous studies, suggest that dispersal is not specifically the result of intraspecific competition. Overall survival at week 8 was 42 per cent (5 hedgehogs) plus two lost animals. This is comparable with previous studies. However, survival fell to 25 per cent (3 animals) plus two lost animals by week 15. Of seven recorded deaths, only one was the result of a failure to thrive and all other mortalities were accidental: four road deaths, one drowned in a pond and one predation. The study concludes that the hazards of the human environment were the principal threat to the welfare and survival of released hedgehogs in the area.
Article
The patterns of dispersal, survival and mortality were analysed in rehabilitated barn owls (Tyto alba) in Spain, including both wild birds after recovery from injuries and captive-bred/released individuals. Comparing these figures to local wild populations released individuals showed greater mortality due to starvation and lower life expectancy. Dispersal did not differ greatly although wild birds in their first year dispersed more than released birds; dispersal was lower in owls released with opportunities of returning for food and shelter (“hacking’’). A massive mortality is recorded after release (about 4 weeks) but after this period surviving owls resembled wild populations in mortality patterns. Owls released following training programmes with live prey showed higher survival values. Owls released during summer months showed better survival than those released in autumn. These findings suggest the importance of Recovery Centres (RC) on owl survival. It is strongly recommended that Spanish RCs should reconsider their methods in order to optimise results and the efficient use of resources.
Article
As a result of an accident in February 1989, 184 000 growing salmon escaped from a seawater farm located in Loch Eriboll in northern Scotland. Later the same year, the behaviour of wild adults and fish of farmed origin was compared in the nearby River Polla. Wild salmon and farmed escapees were distinguished by their morphology, supported by tissue carotenoid analysis. Radio-tagged salmon of both groups and of both sexes were monitored before and during spawning. Bankside observations were made on tagged and untagged wild and farmed fish over the same period. Carotenoid pigments were determined in ova or alevins sampled later from spawning sites along the river's length. Wild and farmed fish of both sexes spawned throughout the river's length. Overall however, wild fish tended to spawn in the river's higher reaches while farmed escapees tended to spawn lower down. Farmed males were more widely distributed at spawning than farmed females. Farmed fish, particularly females, spawned later than wild females. The extent to which these findings may be generalised to other rivers is discussed in relation to the unique character of the River Polla and particularly the presence of a smolt unit on its lower reaches.
Article
The maned sloth is a poorly known species endemic to the highly fragmented and disturbed Brazilian Atlantic forest. As this species has a strictly forest habitat and low dispersion ability, it is susceptible to local extinctions in small and isolated fragments. The project started in 1994, translocating stranded sloths found within or nearby urban zones into forest reserves located in Santa Teresa, state of Espı́rito Santo. Five translocated, radio-collared adults were monitored monthly from periods lasting from 10 months to 3 years after release and data on activity budgets, diet, and home range size were analysed. Results showed that moving and feeding time and distances travelled daily were not significantly related to translocation time (i.e., time, in days, after release). One female, monitored for three years showed, however, a steady and significant decrease in time spent moving from the first to the second to the third year of monitoring (regression Analysis; p0.05). Sloths explored the area more intensively in the first 6 months after release, but minor changes in home ranges were detected even after 3 years. Results suggest that maned sloths are amenable to translocation experiments provided that source and release sites are floristic and ecologically similar. To fully access the success of such experiments though, it is recommended that sloths be monitored for periods longer than 1 year.
Article
We use the phylogenetically based statistical method of independent contrasts to reanalyze the Wolf et al., 1996translocation data set for 181 programs involving 17 mammalian and 28 avian species. Although still novel in conservation and wildlife biology, the incorporation of phylogenetic information into analyses of interspecific comparative data is widely accepted and routinely used in several fields. To facilitate application of independent contrasts, we converted the dichotomous (success/failure) dependent variable (Wolf et al. 1996, Griffith et al. 1989. Translocations as a species conservation tool: status and strategy. Science 245, 477–480) into a more descriptive, continuous variable with the incorporation of persistence of the translocated population beyond the last release year, relative to the species' longevity. For comparison, we present three models: nonphylogenetic multiple logistic regression with the dichotomous dependent variable (the method used by Wolf et al. 1996and Griffith et al. 1989), nonphylogenetic multiple regression with the continuous dependent variable, and multiple regression using phylogenetically independent contrasts with the continuous dependent variable. Results of the phylogenetically based multiple regression analysis indicate statistical significance of three independent variables: habitat quality of the release area, range of the release site relative to the historical distribution of the translocated species, and number of individuals released. Evidence that omnivorous species are more successful than either herbivores or carnivores is also presented. The results of our reanalysis support several of the more important conclusions of the Wolf et al. (1996)and Griffith et al. (1989)studies and increase our confidence that the foregoing variables should be considered carefully when designing a translocation program. However, the phylogenetically based analysis does not support either the Wolf et al. (1996)or Griffith et al. (1989)findings with respect to the statistical significance of taxonomic class (bird vs mammal) and status (game vs threatened, endangered, or sensitive), or the Griffith et al. (1989)findings with respect to the significance of reproductive potential of the species and program length.
Article
Both species showed an annual cycle of body weight, maximal in the summer, minimal in winter. Average differences in body weight between seasons was 12% and 15% in Erinaceus and Hemiechinus respectively. Erinaceus was less sensitive to cold. Maximal activity of Erinaceus was reached in early spring. Not all individuals hibernated; those which did hibernated for only a few days. Hemiechinus showed maximal activity in the summer, with a peak in July. Most individuals hiberated for periods of up to 40 days. Both species are nocturnal. The little activity observed during the day was mainly that of lactating females. Erinaceus spent the days in vegetation lined nests built in depressions above the ground. Hemiechinus nested in self-dug burrows which were well insulated and also served for hibernation. No territorial behaviour was observed; home ranges overlapped. Average home range of Erinaceus was 1.6 ha (both sexes) and 2.8 and 4.9 ha for female and male Hemiechinus, respectively. Erinaceus in omnivorous; some of their food was found in garbage. Hemiechinus is insectivorous and walks large distances every night in search of food.-from Authors
Article
1. Native species are translocated for conservation, commercial, amenity and research purposes. These activities are related, and need to be considered and planned in terms of their effects on biodiversity. 2. Procedures for assessing, implementing and regulating translocations have, however, been subject to largely uncoordinated development; recommendations or guidelines being produced separately for each area of expertise. There is a need to pull together the profuse information concerning specific translocations in order to present a broad approach to the general problems and concerns. 3. Here, the extent and nature of translocations of native species within the UK are reviewed, and recommendations for policy and legislation are made in the context of those currently in use in the UK. The recommendations include the following: (i) improvement of the ways in which relevant information is disseminated; (ii) ease of implementation should be a prime consideration; and (iii) formation of new policy and guidelines should include all UK and international organizations involved in carrying out, advising on, or licensing translocations.
Article
The Orang-utan in Sumatra has long been under heavy hunting pressure, in order to supply foreign zoos, and notwithstanding protection by law. Since the author started his Orang-utan survey in the Gunung Leuser Reserve and established a rehabilitation station for animals confiscated by nature conservation authorities, the situation has somewhat improved, at least in the areas visited by him from time to time. There is, however, another threat to the species— the destruction of its habitat, the rain-forest, either by the local people's shifting cultivation (ladang) or on account of large-scale logging by Indonesian or foreign timber companies. It is hoped that the Leuser, Langkat, and Kluët, reserve complex can be kept inviolate. The rehabilitation project has proved a success, despite predation by a Clouded Leopard. Some of the sub-adult Orang-utan have gone wild in the jungle surrounding the station in which wild specimens are seen regularly. The mode of life and behaviour of both the wild and the rehabilitation station animals are being studied, the contrasts between the animals at the station and their wild counterparts being one of the most interesting aspects of the author's overall research.
Article
Heart rates of bighorn sheep (Ovis canadensis canadensis) were recorded during trapping, handling, and immediately following release of animals with electrocardiogram transmitters. Sustained tachycardia, lasting an average of 117.4 min, was demonstrated in four adult ewes and one 3-year-old ram following trapping and radio instrumentation. Cardiac recovery time of released sheep averaged 10.6 × the maximum recovery time recorded for any disturbance to which these animals were subsequently exposed. The utility of electrocardiogram telemetry in evaluating physiological stress during wildlife capture and marking operations is discussed.
Article
Reintroduction of captive-bred animals is a key approach in conservation attempts for many endangered species, however, post-release survival is often low. Rearing conditions may be unlike those encountered upon release and the animals may not have had experiences necessary for survival in the wild. Animals may also habituate in captivity to stimuli that may pose a danger after release and/or there may be selection for behavioural traits, in particular reduced fearfulness, that may not be suited for the wild. Here, variation in boldness was assessed in captive-bred swift fox (Vulpes velox) and tested for influence on survival after release. Radio-tracked individuals that died in the 6 months following release were those judged previously as bold. In the presence of novel stimuli in captivity, they had left their dens more quickly, approached more closely to the stimuli and shown more activities indicating low fear than did those that survived. These individuals were less suited for release. Future selection of release-candidates on the basis of behavioural variation should enhance the success of reintroduction programmes.
Article
Full 'rehabilitation' of sick and injured wild animals should include restoration to the wild. Few attempts have been made to discover the fate of released 'rehabilitated' animals, a significant omission in terms of animal welfare. They may die, unable to find adequate food or nest sites in unfamiliar places. They may be ostracized or even attacked by wild resident conspecifics.Eight 'rehabilitated' hedgehogs (Erinaceus europaeus) were released into farmland and radio-tracked to monitor their movements and nesting; they were also weighed frequently. Three wild hedgehogs caught on site were studied in parallel.Only one animal remained close to the release site throughout the eight week study. The rest scattered, perhaps seeking more familiar terrain. One animal died, possibly not having fully recovered from its original disorder. Of the seven others, three survived at least seven weeks, but two then met with accidental deaths (drowning and road kill). Contact was lost with four animals, but circumstances suggested that they were probably still alive at least five weeks after release. There was no evidence of negative interaction with local wild hedgehogs nor any indication of difficulty with foraging, nesting or finding their nests again. Body-weights were generally maintained or increased.It is concluded that rehabilitated adult hedgehogs can probably cope well with release.
Article
One commonly used method of managing confiscated wild primates in Latin American countries is to release rehabilitated individuals back to their natural habitats. However, little inform