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1.
PLoS One ; 19(7): e0304740, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39008480

RESUMO

Dietary studies are essential to better understand raptor ecology and resource requirements through time and space, informing species habitat use, interspecific interactions and demographic rates. Methods used to collect data on raptor diets can constrain how dietary analyses can be interpreted. Traditional approaches to study raptor diets, such as analysis of pellets or prey remains, often provide dietary data at the local population level and tend to be restricted to pairs during the breeding season. The increasing use of citizen science data has the potential to provide dietary inferences at larger spatial, demographic and temporal scales. Using web-sourced photography, we explore continental-scale demographic and latitudinal dietary patterns between adult and non-adult Crested Caracaras (Caracara plancus), throughout the species' range across the Americas. We analysed 1,555 photographs of caracaras feeding and found no age effects on the probabilities of different food groups being included in photographs. The probability of reptiles being included in photographs of caracaras from the northern population was significantly higher than those from the southern population, with the opposite pattern for birds. There were significant latitudinal effects with the probabilities of fishes and invertebrates in the diet of northern caracaras increasing towards the equator. Contrastingly, the probability of mammals in the diet increased away from the equator for both populations. Assuming the focal species is well-sampled, web-sourced photography can improve our understanding of raptor diets at large-scales and complements more traditional approaches. This approach is more accessible to raptor researchers without access to the field or expertise in physical prey identification techniques.


Assuntos
Dieta , Fotografação , Aves Predatórias , Animais , Comportamento Alimentar , Internet , Ecossistema , Padrões Dietéticos
2.
Ecol Evol ; 14(5): e11391, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38779533

RESUMO

Predicting the effects of global environmental changes on species distribution is a top conservation priority, particularly for large carnivores, that contribute to regulating and maintaining ecosystems. As the most widespread and adaptable large felid, ranging across Africa and Asia, leopards are crucial to many ecosystems as both keystone and umbrella species, yet they are threatened across their ranges. We used intraspecific species distribution models (SDMs) to predict changes in range suitability for leopards under future climate and land-use change and identify conservation gaps and opportunities. We generated intraspecific SDMs for the three western leopard subspecies, the African, Panthera pardus pardus; Arabian, Panthera pardus nimr; and Persian, Panthera pardus tulliana, leopards, and overlapped predictions with protected areas (PAs) coverage. We show that leopard subspecies differ in their environmental associations and vulnerability to future changes. The African and Arabian leopards are predicted to lose ~25% and ~14% of their currently suitable range, respectively, while the Persian leopard is predicted to experience ~12% range gains. We found that most areas predicted to be suitable were not protected, with only 4%-16% of the subspecies' ranges falling inside PAs, and that these proportions will decrease in the future. The highly variable responses we found between leopard subspecies highlight the importance of considering intraspecific variation when modelling vulnerability to climate and land-use changes. The predicted decrease in proportion of suitable ranges falling inside PAs threatens global capacity to effectively conserve leopards because survival rates are substantially lower outside PAs due to persecution. Hence, it is important to work with local communities to address negative human-wildlife interactions and to restore habitats to retain landscape connectivity where PA coverage is low. On the other hand, the predicted increase in range suitability across southern Europe presents opportunities for expansion outside of their contemporary range, capitalising on European rewilding schemes.

3.
Animals (Basel) ; 12(22)2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36428396

RESUMO

Trade in lion parts associated with cultural and traditional use is poorly understood. Here we sought to better understand the role and use of lion body parts in the commercial traditional medicine (muthi) trade of South Africa. In 2019 we conducted a semi-structured questionnaire survey of muthi traders (n = 10) and traditional healers (n = 20) which explored the significance and symbolism of lions, traded parts and preferences, sources and supply of lion parts, and perceived sustainability of lion derivatives in the South African muthi trade. Our results suggest a cultural importance of lion associated with the umndawu ancestral spirit in particular, as well as in the training and practice of cultural-spiritual healers. Lion paws and parts thereof were most frequently reported as sold by traders and demanded by healers, correlating with recent trends in body-part removals from lion mortalities. Respondents indicated that lion parts were obtained from a variety of sources including wild lion populations in neighbouring countries and captive-breeding farms. Our findings are discussed relative to current concerns in lion conservation and highlight a need for further understanding of the traditional medicine complex, the influence that ancestral spirits have on lion body-part trade, and increased engagement with traditional medicine stakeholders.

4.
G3 (Bethesda) ; 12(12)2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36250809

RESUMO

The big cats (genus Panthera) represent some of the most popular and charismatic species on the planet. Although some reference genomes are available for this clade, few are at the chromosome level, inhibiting high-resolution genomic studies. We assembled genomes from 3 members of the genus, the tiger (Panthera tigris), the snow leopard (Panthera uncia), and the African leopard (Panthera pardus pardus), at chromosome or near-chromosome level. We used a combination of short- and long-read technologies, as well as proximity ligation data from Hi-C technology, to achieve high continuity and contiguity for each individual. We hope that these genomes will aid in further evolutionary and conservation research of this iconic group of mammals.


Assuntos
Panthera , Tigres , Animais , Panthera/genética , Tigres/genética , Genoma , Cromossomos/genética
5.
Evol Appl ; 15(1): 22-39, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35126646

RESUMO

Conservation translocations have become an important management tool, particularly for large wildlife species such as the lion (Panthera leo). When planning translocations, the genetic background of populations needs to be taken into account; failure to do so risks disrupting existing patterns of genetic variation, ultimately leading to genetic homogenization, and thereby reducing resilience and adaptability of the species. We urge wildlife managers to include knowledge of the genetic background of source/target populations, as well as species-wide patterns, in any management intervention. We present a hierarchical decision-making tool in which we list 132 lion populations/lion conservation units and provide information on genetic assignment, uncertainty and suitability for translocation for each source/target combination. By including four levels of suitability, from 'first choice' to 'no option', we provide managers with a range of options. To illustrate the extent of international trade of lions, and the potential disruption of natural patterns of intraspecific diversity, we mined the CITES Trade Database for estimated trade quantities of live individuals imported into lion range states during the past 4 decades. We identified 1056 recorded individuals with a potential risk of interbreeding with wild lions, 772 being captive-sourced. Scoring each of the records with our decision-making tool illustrates that only 7% of the translocated individuals were 'first choice' and 73% were 'no option'. We acknowledge that other, nongenetic factors are important in the decision-making process, and hence a pragmatic approach is needed. A framework in which source/target populations are scored based on suitability is not only relevant to lion, but also to other species of wildlife that are frequently translocated. We hope that the presented overview supports managers to include genetics in future management decisions and contributes towards conservation of the lion in its full diversity.

6.
PLoS One ; 16(4): e0249306, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33798210

RESUMO

From 2008 to 2018, South Africa permitted the export of captive-bred African lion (Panthera leo) skeletons to Southeast Asia under CITES Appendix II. Legal exports rose from approximately 50 individuals in 2008 to a maximum of 1,771 skeletons in 2016, and has led to ongoing concerns over possible laundering of non-lion, multiple-source and wild-sourced bones. South Africa is required under its obligations to CITES to employ mechanisms for monitoring and reporting trade, and to limit the potential for illegal trade and laundering of lion and other large felid bones. Monitoring tools for legal trade are critical to compliance with CITES. Here we evaluate the CITES-compliance procedure implemented by South Africa for export of lion bones and identify six essential general points for consideration in the implementation of animal export quota compliance protocols. We provide specific insight into the South African lion bone export monitoring system through: i) outlining the protocols followed; ii) assessing the utility of cranial morphology to identify species; iii) evaluating skeleton consignment weight as a monitoring tool; and iv) presenting molecular (DNA) species assignment and pairwise-comparative sample matching of individuals. We describe irregularities and illicit behaviour detected in the 2017 and 2018 lion bone quotas. Notably, we report that the compliance procedure successfully identified and prevented the attempted laundering of a tiger (P. tigris) skeleton in 2018. We emphasise the utility of mixed-method protocols for the monitoring of compliance in CITES Appendix II export quota systems.


Assuntos
Conservação dos Recursos Naturais/economia , Espécies em Perigo de Extinção/economia , Fidelidade a Diretrizes/estatística & dados numéricos , Leões , Crânio , Animais , Cruzamento , África do Sul
7.
Ecol Evol ; 10(8): 3605-3619, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32313621

RESUMO

Anthropogenic mortality of wildlife is typically inferred from measures of the absolute decline in population numbers. However, increasing evidence suggests that indirect demographic effects including changes to the age, sex, and social structure of populations, as well as the behavior of survivors, can profoundly impact population health and viability. Specifically, anthropogenic mortality of wildlife (especially when unsustainable) and fragmentation of the spatial distribution of individuals (home-ranges) could disrupt natal dispersal mechanisms, with long-term consequences to genetic structure, by compromising outbreeding behavior and gene flow. We investigate this threat in African leopards (Panthera pardus pardus), a polygynous felid with male-biased natal dispersal. Using a combination of spatial (home-range) and genetic (21 polymorphic microsatellites) data from 142 adult leopards, we contrast the structure of two South African populations with markedly different histories of anthropogenically linked mortality. Home-range overlap, parentage assignment, and spatio-genetic autocorrelation together show that historical exploitation of leopards in a recovering protected area has disrupted and reduced subadult male dispersal, thereby facilitating opportunistic male natal philopatry, with sons establishing territories closer to their mothers and sisters. The resultant kin-clustering in males of this historically exploited population is comparable to that of females in a well-protected reserve and has ultimately led to localized inbreeding. Our findings demonstrate novel evidence directly linking unsustainable anthropogenic mortality to inbreeding through disrupted dispersal in a large, solitary felid and expose the genetic consequences underlying this behavioral change. We therefore emphasize the importance of managing and mitigating the effects of unsustainable exploitation on local populations and increasing habitat fragmentation between contiguous protected areas by promoting in situ recovery and providing corridors of suitable habitat that maintain genetic connectivity.

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