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1.
Evol Appl ; 16(1): 111-125, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36699120

RESUMO

Threatened species are frequently patchily distributed across small wild populations, ex situ populations managed with varying levels of intensity and reintroduced populations. Best practice advocates for integrated management across in situ and ex situ populations. Wild addax (Addax nasomaculatus) now number fewer than 100 individuals, yet 1000 of addax remain in ex situ populations, which can provide addax for reintroductions, as has been the case in Tunisia since the mid-1980s. However, integrated management requires genetic data to ascertain the relationships between wild and ex situ populations that have incomplete knowledge of founder origins, management histories, and pedigrees. We undertook a global assessment of genetic diversity across wild, ex situ and reintroduced populations in Tunisia to assist conservation planning for this Critically Endangered species. We show that the remnant wild populations retain more mitochondrial haplotypes that are more diverse than the entirety of the ex situ populations across Europe, North America and the United Arab Emirates, and the reintroduced Tunisian population. Additionally, 1704 SNPs revealed that whilst population structure within the ex situ population is minimal, each population carries unique diversity. Finally, we show that careful selection of founders and subsequent genetic management is vital to ensure genetic diversity is provided to, and minimize drift and inbreeding within reintroductions. Our results highlight a vital need to conserve the last remaining wild addax population, and we provide a genetic foundation for determining integrated conservation strategies to prevent extinction and optimize future reintroductions.

2.
Integr Zool ; 18(1): 110-128, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34937133

RESUMO

Of the approximately 30 extant species of pika (Ochotona; Ochotonidae; Lagomorpha), at least 23 occur in China. Of these, 8 are endemic, and 3 are classified as Endangered by the IUCN. Research into most Chinese species is scarce, and there is much to learn about basic aspects of their ecology. We reviewed the literature on the 23 Chinese Ochotona species, with the aim of highlighting knowledge gaps and biases in research allocation. Specifically, we identify (1) which pika species receive the most attention from researchers, (2) which topics are the most frequently studied, and (3) how well research satisfies conservation priorities. We covered a total of 879 articles, most of which were written in English or Chinese. Around 75% of all publications focused on the plateau pika Ochotona curzoniae. Seven species were represented by 10 or fewer publications each. Endangered and endemic species were particularly poorly represented. 204 papers treated pikas as a pest, while 13 studied conservation issues. Nine species were considered possible targets for pest control, including some poorly known endemics. We make some recommendations on how research into Chinese Ochotona could be improved, including: (1) recognizing that the current species-level taxonomy may be an ineffective way to prioritize conservation research in Ochotona, (2) directing more research toward threatened and endemic species, subspecies, and populations, (3) researching the ecosystem engineering effects of pikas, (4) collecting basic data on natural history of the many understudied species, and (5) researching threats, including climate change and pest control campaigns.


Assuntos
Ecossistema , Lagomorpha , Animais , China , Ecologia , Pesquisa
3.
Int Environ Agreem ; 22(3): 577-597, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35309248

RESUMO

Zoonotic viruses have sacrificed hundreds of millions of people throughout human history. There are currently 1.7 million unidentified viruses estimated to be circulating in mammal and bird populations. It is foreseeable that in the near future, another of these will transmit to people, heralding the start of the next pandemic-one potentially more deadly than COVID-19. At the core of this article is a call for pre-emptive protection of the natural environment and its regenerative systems as the first fundamental step in the prevention of future epidemics and pandemics. While zoonoses originate in nature, the predominant legal discipline, managing these crises, is international health law which is invoked reactively once an outbreak has been reported. In this paper, we identify the need for a legal shift in epidemic and pandemic responses. In particular, we call for the incorporation of international environmental agreements to prevent the initial viral spillover from animal to human populations. We propose a strategy of strengthening existing agreements and a coupling of legal disciplines, such as health and environmental law, emphasizing the need for synergies across legal disciplines to enhance the emergence and management of future pandemics and epidemics. We introduce Coupled Human and Natural Systems (CHANS) Law to frame the required integration across legal instruments to regulate inextricably human-nature connections and advocate for the development of a Convention on Epidemics and Pandemics.

4.
Heredity (Edinb) ; 127(6): 522-534, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34743188

RESUMO

Understanding the spatial structure of genetic diversity provides insights into a populations' genetic status and enables assessment of its capacity to counteract the effects of genetic drift. Such knowledge is particularly scarce for the snow leopard, a conservation flagship species of Central Asia mountains. Focusing on a snow leopard population in the Qilian mountains of Gansu Province, China, we characterised the spatial genetic patterns by incorporating spatially explicit indices of diversity and multivariate analyses, based on different inertia levels of Principal Component Analysis (PCA). We compared two datasets differing in the number of loci and individuals. We found that genetic patterns were significantly spatially structured and were characterised by a broad geographical division coupled with a fine-scale cline of differentiation. Genetic admixture was detected in two adjoining core areas characterised by higher effective population size and allelic diversity, compared to peripheral localities. The power to detect significant spatial relationships depended primarily on the number of loci, and secondarily on the number of PCA axes. Spatial patterns and indices of diversity highlighted the cryptic structure of snow leopard genetic diversity, likely driven by its ability to disperse over large distances. In combination, the species' low allelic richness and large dispersal ability result in weak genetic differentiation related to major geographical features and isolation by distance. This study illustrates how cryptic genetic patterns can be investigated and analysed at a fine spatial scale, providing insights into the spatially variable isolation effects of both geographic distance and landscape resistance.


Assuntos
Panthera , Animais , China , Variação Genética , Genética Populacional , Geografia , Humanos , Repetições de Microssatélites , Panthera/genética , Densidade Demográfica
5.
Ecol Evol ; 10(14): 7686-7712, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32760557

RESUMO

Replicated multiple scale species distribution models (SDMs) have become increasingly important to identify the correct variables determining species distribution and their influences on ecological responses. This study explores multi-scale habitat relationships of the snow leopard (Panthera uncia) in two study areas on the Qinghai-Tibetan Plateau of western China. Our primary objectives were to evaluate the degree to which snow leopard habitat relationships, expressed by predictors, scales of response, and magnitude of effects, were consistent across study areas or locally landcape-specific. We coupled univariate scale optimization and the maximum entropy algorithm to produce multivariate SDMs, inferring the relative suitability for the species by ensembling top performing models. We optimized the SDMs based on average omission rate across the top models and ensembles' overlap with a simulated reference model. Comparison of SDMs in the two study areas highlighted landscape-specific responses to limiting factors. These were dependent on the effects of the hydrological network, anthropogenic features, topographic complexity, and the heterogeneity of the landcover patch mosaic. Overall, even accounting for specific local differences, we found general landscape attributes associated with snow leopard ecological requirements, consisting of a positive association with uplands and ridges, aggregated low-contrast landscapes, and large extents of grassy and herbaceous vegetation. As a means to evaluate the performance of two bias correction methods, we explored their effects on three datasets showing a range of bias intensities. The performance of corrections depends on the bias intensity; however, density kernels offered a reliable correction strategy under all circumstances. This study reveals the multi-scale response of snow leopards to environmental attributes and confirms the role of meta-replicated study designs for the identification of spatially varying limiting factors. Furthermore, this study makes important contributions to the ongoing discussion about the best approaches for sampling bias correction.

6.
J Wildl Dis ; 56(4): 815-822, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32402236

RESUMO

From March to April 2017, a total of 147 free-ranging spur-thighed tortoises (Testudo graeca) was captured in different habitat types of northern Tunisia and examined for tick infestation. A total of 134 was infested, yielding an infestation prevalence of 91.2%. From these tortoises, 1,174 ticks were collected, a subsample (10%, n=120) of which was randomly selected and identified; the remaining ticks were stored at -80 C and examined for zoonotic pathogens. Only adult Hyalomma aegyptium were found among the subsample of ticks collected for spur-thighed tortoise. The prevalence of tick infestation did not vary significantly within the study area but differences in intensity were observed in relation to the size of tortoises and the vegetation coverage. Our results provide strong evidence that adult H. aegyptium is the predominant tick species found on wild spur-thighed tortoises in northern Tunisia, where the species is commonly traded illegally across the Mediterranean Basin. Considering the potential transmission of several zoonotic pathogens by H. aegyptium to humans, we highlight the need to develop a surveillance system to prevent the introduction and the spread of tick-borne pathogens in the Mediterranean Basin.


Assuntos
Ixodidae , Infestações por Carrapato/veterinária , Tartarugas/parasitologia , Animais , Feminino , Masculino , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/parasitologia , Tunísia/epidemiologia
7.
Proc Biol Sci ; 286(1902): 20190345, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-31064305

RESUMO

Parent sex ratio allocation has consequences for individual fitness, population dynamics, and conservation. Theory predicts that parents should adjust offspring sex ratio when the fitness returns of producing male or female offspring varies. Previous studies have assumed that only mothers are capable of biasing offspring sex ratios, but have neglected fathers, given the expectation of an equal proportion of X- and Y-chromosome-bearing (CBS) sperm in ejaculates due to sex chromosome segregation at meiosis. This assumption has been recently refuted and both paternal fertility and paternal genetic quality have been shown to bias sex ratios. Here, we simultaneously test the relative contribution of paternal, maternal, and individual genetic quality, as measured by inbreeding, on the probability of being born a son or a daughter, using pedigree and lifelong offspring sex ratio data for the eastern bongo ( Tragelaphus eurycerus isaaci). Our models showed first, that surprisingly, as individual inbreeding decreases the probability of being born male increases, second, that paternal genetic effects on sex ratio were stronger than maternal genetic effects (which were absent). Furthermore, paternal effects were opposite in sign to those predicted; father inbreeding increases the probability of having sons. Previous paternal effects have been interpreted as adaptive due to sex-specific inbreeding depression for reproductive traits. We argue that in the eastern bongo, the opposite sign of the paternal effect on sex ratios results from a reversed sex-specific inbreeding depression pattern (present for female but not male reproductive traits). We anticipate that this research will help stimulate research on evolutionary constraints to sex ratios. Finally, the results open a new avenue of research to predict sex ratio allocation in an applied conservation context. Future models of sex ratio allocation should also include the predicted inbreeding level of the offspring and paternal inbreeding levels.


Assuntos
Antílopes/genética , Herança Paterna , Reprodução/genética , Razão de Masculinidade , Animais , Feminino , Endogamia , Masculino , Modelos Biológicos
8.
PLoS One ; 13(11): e0204764, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30408034

RESUMO

Protection of the world's remaining forests and biodiversity is a matter of global concern. Yunnan, China is home to China's only mainland tropical rainforests, and 20% of China's total biodiversity. Despite restoration measures and establishment of new protected areas, this region is still experiencing biodiversity loss due to inadequate management and monitoring. We evaluate restoration success of China's tropical forests in Xishuangbanna National Nature Reserve (XSBN-NNR), Yunnan, China using dung beetles as an indicator taxon. We sampled across a land-use gradient of human alteration: protected forest, restored forest, community owned forest, and rubber plantation. We collected 3,748 dung beetles from 21 species over a 3 month period. Multivariate analyses revealed unique assemblages in each land-use category, but with restored forest most similar to protected areas, suggesting restoration success in this region. Community forests were more diverse than plantations, suggesting that community forests may be a valuable and practical conservation tool in this region. Most species were generalists, although some had dietary and habitat preferences. Furthermore, dietary niche breadths were, on average, higher in disturbed areas, suggesting that disturbance may result in dietary changes. We show that restoration of tropical forests appears to be successful for a key ecological and biological indicator group- dung beetles. Furthermore, community-owned forests appear to be valuable and practical method of maintaining ecosystem health and biodiversity in the region. Future management in this region would likely benefit from encouragement to maintain community-owned forests, economic incentives for restoring farmland to forest, and increased environmental monitoring across the land-use gradient.


Assuntos
Biodiversidade , Besouros/fisiologia , Conservação dos Recursos Naturais , Agricultura Florestal/métodos , Floresta Úmida , Animais , China , Humanos
9.
PLoS One ; 13(1): e0191770, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29370251

RESUMO

The International Union for the Conservation of Nature (IUCN) Red List classifies species according to their risk of extinction, informing local to global conservation decisions. Here we look to advance the estimation of generation length, which is used as a time-scalar in the Red List as a way of accounting for differences in species' life-histories. We calculated or predicted generation length for 86 species of antelope following the Rspan approach. We also tested the importance of both allometry (body-mass) and phylogeny (phylogenetic eigenvectors) as predictors of generation length within a Phylogenetic Eigenvector Map (PEM) framework. We then evaluated the predictive power of this PEM and two binning approaches, following a leave-one-out cross-validation routine. We showed that captive and wild longevity data are nonequivalent and that both body-mass and phylogeny are important predictors for generation length (body-mass explained 64% and phylogeny 36% of the partitioned explained variance). Plus, both the PEM, and the binning approach that included both taxonomic rank and body-mass, had good predictive power and therefore are suitable for extrapolating generation length to missing-data species. Therefore, based on our findings, we advise separating captive and wild data when estimating generation length, and considering the implications of wild and captive data more widely in life-history analyses. We also recommend that body-mass and phylogeny should be used in combination, preferably under a PEM framework (as it was less reliant on available reference species and more explicitly accounts for phylogenetic relatedness) or a binning approach if a PEM is not feasible, to extrapolate generation length to missing-data species. Overall, we provide a transparent, consistent and transferable workflow for improving the use of the Rspan method to calculate generation length for the IUCN Red List.


Assuntos
Conservação dos Recursos Naturais , Animais , Antílopes/fisiologia , Modelos Teóricos , Filogenia , Reprodução
10.
PLoS One ; 11(5): e0155309, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27171203

RESUMO

Human population growth and concomitant increases in demand for natural resources pose threats to many wildlife populations. The landscapes used by the endangered snow leopard (Panthera uncia) and their prey is increasingly subject to major changes in land use. We aimed to assess the influence of 1) key human activities, as indicated by the presence of mining and livestock herding, and 2) the presence of a key prey species, the blue sheep (Pseudois nayaur), on probability of snow leopard site use across the landscape. In Gansu Province, China, we conducted sign surveys in 49 grid cells, each of 16 km2 in size, within a larger area of 3392 km2. We analysed the data using likelihood-based habitat occupancy models that explicitly account for imperfect detection and spatial auto-correlation between survey transect segments. The model-averaged estimate of snow leopard occupancy was high [0.75 (SE 0.10)], but only marginally higher than the naïve estimate (0.67). Snow leopard segment-level probability of detection, given occupancy on a 500 m spatial replicate, was also high [0.68 (SE 0.08)]. Prey presence was the main determinant of snow leopard site use, while human disturbances, in the form of mining and herding, had low predictive power. These findings suggest that snow leopards continue to use areas very close to such disturbances, as long as there is sufficient prey. Improved knowledge about the effect of human activity on large carnivores, which require large areas and intact prey populations, is urgently needed for conservation planning at the local and global levels. We highlight a number of methodological considerations that should guide the design of such research.


Assuntos
Ecossistema , Felidae/fisiologia , Animais , China , Conservação dos Recursos Naturais , Geografia , Humanos , Modelos Teóricos , Probabilidade
11.
Integr Zool ; 11(4): 308-21, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27135283

RESUMO

China holds the greatest proportion of the snow leopard's (Panthera uncia) global range and is central to their conservation. The country is also undergoing unprecedented economic growth, which increases both the threats to the snow leopard and the opportunities for its conservation. In this paper we aim to review published literature (from 1950 to 2014) in English and Mandarin on snow leopard ecology and conservation in China in order to identify thematic and geographic research gaps and propose research priorities. We first retrieved all published items that considered snow leopards in China (n = 106). We extracted from these papers 274 reports of snow leopard presence in China. We then reviewed a subset of papers (n = 33) of this literature, which specifically focused on snow leopard ecology and conservation within China. We introduced a thematic framework that allows a structured and comprehensive assessment of findings. This framework recognizes 4 critical and interrelated topics underpinning snow leopard ecology and conservation: habitat (distribution and protected area coverage); prey (distribution and abundance, predator-prey relationships); human interactions (hunting and trade, livestock interactions and conflicts); and the underlying policy context. Significant gains in knowledge as well as research gaps and priorities are discussed with reference to our framework. The modest quantity and limited scope of published research on the snow leopard in China calls for a continued and intensified effort to inform and support national conservation policies.


Assuntos
Conservação dos Recursos Naturais , Panthera , Animais , China , Ecossistema , Atividades Humanas , Comportamento Predatório
12.
PLoS One ; 10(9): e0134815, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26322682

RESUMO

When densities of large carnivores fall below certain thresholds, dramatic ecological effects can follow, leading to oversimplified ecosystems. Understanding the population status of such species remains a major challenge as they occur in low densities and their ranges are wide. This paper describes the use of non-invasive data collection techniques combined with recent spatial capture-recapture methods to estimate the density of snow leopards Panthera uncia. It also investigates the influence of environmental and human activity indicators on their spatial distribution. A total of 60 camera traps were systematically set up during a three-month period over a 480 km2 study area in Qilianshan National Nature Reserve, Gansu Province, China. We recorded 76 separate snow leopard captures over 2,906 trap-days, representing an average capture success of 2.62 captures/100 trap-days. We identified a total number of 20 unique individuals from photographs and estimated snow leopard density at 3.31 (SE = 1.01) individuals per 100 km2. Results of our simulation exercise indicate that our estimates from the Spatial Capture Recapture models were not optimal to respect to bias and precision (RMSEs for density parameters less or equal to 0.87). Our results underline the critical challenge in achieving sufficient sample sizes of snow leopard captures and recaptures. Possible performance improvements are discussed, principally by optimising effective camera capture and photographic data quality.


Assuntos
Ecossistema , Felidae , Animais , China , Densidade Demográfica , Dinâmica Populacional
13.
PLoS One ; 10(6): e0129748, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26086191

RESUMO

Accurate and spatially-appropriate ecosystem service valuations are vital for decision-makers and land managers. Many approaches for estimating ecosystem service value (ESV) exist, but their appropriateness under specific conditions or logistical limitations is not uniform. The most accurate techniques are therefore not always adopted. Six different assessment approaches were used to estimate ESV for a National Nature Reserve in southwest China, across different management zones. These approaches incorporated two different land-use land cover (LULC) maps and development of three economic valuation techniques, using globally or locally-derived data. The differences in ESV across management zones for the six approaches were largely influenced by the classifications of forest and farmland and how they corresponded with valuation coefficients. With realistic limits on access to time, data, skills and resources, and using acquired estimates from globally-relevant sources, the Buffer zone was estimated as the most valuable (2.494 million ± 1.371 million CNY yr(-1) km(-2)) and the Non-protected zone as the least valuable (770,000 ± 4,600 CNY yr(-1) km(-2)). However, for both LULC maps, when using the locally-based and more time and skill-intensive valuation approaches, this pattern was generally reversed. This paper provides a detailed practical example of how ESV can differ widely depending on the availability and appropriateness of LULC maps and valuation approaches used, highlighting pitfalls for the managers of protected areas.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecossistema , China , Tomada de Decisões , Humanos
14.
Dongwuxue Yanjiu ; 36(2): 72-8, 2015 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-25855225

RESUMO

Many ecological studies and conservation management plans employ noninvasive scat sampling based on the assumption that species' scats can be correctly identified in the field. However, in habitats with sympatric similarly sized carnivores, misidentification of scats is frequent and can lead to bias in research results. To address the scat identification dilemma, molecular scatology techniques have been developed to extract DNA from the donor cells present on the outer lining of the scat samples. A total of 100 samples were collected in the winter of 2009 and 2011 in Taxkorgan region of Xinjiang, China. DNA was extracted successfully from 88% of samples and genetic species identification showed that more than half the scats identified in the field as snow leopard (Panthera uncia) actually belonged to fox (Vulpes vulpes). Correlation between scat characteristics and species were investigated, showing that diameter and dry weight of the scat were significantly different between the species. However it was not possible to define a precise range of values for each species because of extensive overlap between the morphological values. This preliminary study confirms that identification of snow leopard feces in the field is misleading. Research that relies upon scat samples to assess distribution or diet of the snow leopard should therefore employ molecular scatology techniques. These methods are financially accessible and employ relatively simple laboratory procedures that can give an indisputable response to species identification from scats.


Assuntos
DNA/genética , Cães/genética , Fezes/química , Felidae/genética , Raposas/genética , Lobos/genética , Animais , China , DNA/química , Especificidade da Espécie
15.
PLoS One ; 8(9): e73856, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24086298

RESUMO

Decline in wild populations as a result of anthropogenic impact is widely considered to have evolutionary consequences for the species concerned. Here we examine changes in developmental stability in the painted hunting dog (Lycaon pictus), which once occupied most of sub-Saharan Africa but has undergone a dramatic population decline in the last century. Fluctuating asymmetry (FA) was used as an indicator of developmental stability and measured in museum skull specimens spanning a hundred year period. A comparison with the more ubiquitous black-backed jackal (Canis mesomelas) revealed FA in L. pictus to be high. Furthermore, the data indicate a temporal increase in FA over time in L. pictus, corresponding to the period of its population decline. The high rate of change is compatible with genetic drift although environmental factors are also likely to be important. Lowering developmental stability over time may have direct fitness consequences and as such represents an unacknowledged threat to future resilience of the population.


Assuntos
Evolução Biológica , Canidae/fisiologia , Espécies em Perigo de Extinção , Animais , Canidae/genética , Fósseis , Fenótipo
16.
Ecology ; 94(7): 1519-30, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23951712

RESUMO

How best to manage forest patches, mitigate the consequences of forest fragmentation, and enable landscape permeability are key questions facing conservation scientists and managers. Many temperate forests have become increasingly fragmented, resulting in reduced interior forest habitat, increased edge habitats, and reduced connectivity. Using a citizen science landscape-scale mark-release-recapture study on 87 macro-moth species, we investigated how both life-history traits and landscape characteristics predicted macro-moth responses to forest fragmentation. Wingspan, wing shape, adult feeding, and larval feeding guild predicted macro-moth mobility, although the predictive power of wingspan and wing shape depended on the species' affinity to the forest. Solitary trees and small fragments functioned as "stepping stones," especially when their landscape connectivity was increased, by being positioned within hedgerows or within a favorable matrix. Mobile forest specialists were most affected by forest fragmentation: despite their high intrinsic dispersal capability, these species were confined mostly to the largest of the forest patches due to their strong affinity for the forest habitat, and were also heavily dependent on forest connectivity in order to cross the agricultural matrix. Forest fragments need to be larger than five hectares and to have interior forest more than 100 m from the edge in order to sustain populations of forest specialists. Our study provides new insights into the movement patterns of a functionally important insect group, with implications for the landscape-scale management of forest patches within agricultural landscapes.


Assuntos
Ecossistema , Mariposas/fisiologia , Árvores , Animais , Demografia , Monitoramento Ambiental
17.
Folia Primatol (Basel) ; 83(3-6): 288-98, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23363589

RESUMO

Primates and felids often occupy the same landscape, hence evolutionary theory predicts that proximate predator-prey mechanisms will influence both groups' ecology. Erythrocebus patas are potentially vulnerable to a number of predators and exhibit an array of morphological and behavioural predator avoidance strategies. Here, two concurrent studies, one on E. patas and one on the mammalian carnivore assemblage, in the Acacia drepanolobium woodland of Sweetwaters Game Reserve (SGR), Laikipia, Kenya, provided an opportunity to explore interactions between the two taxa, and serve as an example whereby data from different methodologies can be interpreted together. Static interaction models of predation risk due to leopards, lions, black-backed jackals and spotted hyaenas were developed and interpreted with actual and potential dietary information, collected during the study and from the literature, respectively. This amalgamation of field data showed that E. patas in SGR avoided areas with the highest risk of encountering leopards. Furthermore, the patterns of E. patas ranging suggested that males travelling in small bachelor groups were less affected by other predators than females in large social groups. Bachelor males avoided only the most risky areas of the reserve.


Assuntos
Carnívoros/fisiologia , Erythrocebus patas/fisiologia , Cadeia Alimentar , Animais , Ecossistema , Feminino , Quênia , Masculino , Modelos Biológicos , Análise Espacial
18.
PLoS One ; 6(12): e28904, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22194946

RESUMO

In the UK, attempts since the 1970s to control the incidence of bovine tuberculosis (bTB) in cattle by culling a wildlife host, the European badger (Meles meles), have produced equivocal results. Culling-induced social perturbation of badger populations may lead to unexpected outcomes. We test predictions from the 'perturbation hypothesis', determining the impact of culling operations on badger populations, movement of surviving individuals and the influence on the epidemiology of bTB in badgers using data dervied from two study areas within the UK Government's Randomised Badger Culling Trial (RBCT). Culling operations did not remove all individuals from setts, with between 34-43% of badgers removed from targeted social groups. After culling, bTB prevalence increased in badger social groups neighbouring removals, particularly amongst cubs. Seventy individual adult badgers were fitted with radio-collars, yielding 8,311 locational fixes from both sites between November 2001 and December 2003. Home range areas of animals surviving within removed groups increased by 43.5% in response to culling. Overlap between summer ranges of individuals from Neighbouring social groups in the treatment population increased by 73.3% in response to culling. The movement rate of individuals between social groups was low, but increased after culling, in Removed and Neighbouring social groups. Increased bTB prevalence in Neighbouring groups was associated with badger movements both into and out of these groups, although none of the moving individuals themselves tested positive for bTB. Significant increases in both the frequency of individual badger movements between groups and the emergence of bTB were observed in response to culling. However, no direct evidence was found to link the two phenomena. We hypothesise that the social disruption caused by culling may not only increase direct contact and thus disease transmission between surviving badgers, but may also increase social stress within the surviving population, causing immunosuppression and enhancing the expression of disease.


Assuntos
Comportamento Animal/fisiologia , Mustelidae/fisiologia , Comportamento Social , Tuberculose Bovina/epidemiologia , Animais , Bovinos , Feminino , Masculino , Prevalência , Reino Unido/epidemiologia
19.
Proc Biol Sci ; 274(1626): 2769-77, 2007 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-17725974

RESUMO

The Eurasian badger (Meles meles) is implicated in the transmission of bovine tuberculosis (TB) to cattle in the UK and Republic of Ireland. Badger culling has been employed for the control of TB in cattle in both countries, with varying results. Social perturbation of badger populations following culling has been proposed as an explanation for the failure of culling to consistently demonstrate significant reductions in cattle TB. Field studies indicate that culling badgers may result in increased immigration into culled areas, disruption of territoriality, increased ranging and mixing between social groups. Our analysis shows that some measures of sociality may remain significantly disrupted for up to 8 years after culling. This may have epidemiological consequences because previous research has shown that even in a relatively undisturbed badger population, movements between groups are associated with increases in the incidence of Mycobacterium bovis infection. This is consistent with the results from a large-scale field trial, which demonstrated decreased benefits of culling at the edges of culled areas, and an increase in herd breakdown rates in neighbouring cattle.


Assuntos
Mustelidae/fisiologia , Comportamento Social , Tuberculose Bovina/prevenção & controle , Animais , Bovinos , Reservatórios de Doenças , Feminino , Masculino , Atividade Motora , Mustelidae/microbiologia , Mycobacterium bovis , Dinâmica Populacional
20.
J Wildl Dis ; 42(1): 179-81, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16699163

RESUMO

Antibodies to Toxoplasma gondii were detected in samples collected from 90 live-trapped adult Eurasian badgers (Meles meles) sampled at three sites (two agricultural and one woodland) in southern England. Serum was tested using a qualitative latex agglutination test procedure and 63 of 90 (70%) badgers tested positive for T. gondii antibodies. Antibody prevalence varied between the sites; 67% and 77% of badgers from agricultural sites and 39% from a nonagricultural site tested positive.


Assuntos
Anticorpos Antiprotozoários/sangue , Mustelidae/parasitologia , Toxoplasma/imunologia , Toxoplasmose Animal/epidemiologia , Animais , Animais Selvagens/parasitologia , Inglaterra/epidemiologia , Testes de Fixação do Látex/métodos , Testes de Fixação do Látex/veterinária , Estudos Soroepidemiológicos
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