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1.
Evol Appl ; 17(3): e13676, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38505216

RESUMO

The decline of lions (Panthera leo) in Kenya has raised conservation concerns about their overall population health and long-term survival. This study aimed to assess the genetic structure, differentiation and diversity of lion populations in the country, while considering the influence of past management practices. Using a lion-specific Single Nucleotide Polymorphism (SNP) panel, we genotyped 171 individuals from 12 populations representative of areas with permanent lion presence. Our results revealed a distinct genetic pattern with pronounced population structure, confirmed a north-south split and found no indication of inbreeding in any of the tested populations. Differentiation seems to be primarily driven by geographical barriers, human presence and climatic factors, but management practices may have also affected the observed patterns. Notably, the Tsavo population displayed evidence of admixture, perhaps attributable to its geographic location as a suture zone, vast size or past translocations, while the fenced populations of Lake Nakuru National Park and Solio Ranch exhibited reduced genetic diversity due to restricted natural dispersal. The Amboseli population had a high number of monomorphic loci likely reflecting a historical population decline. This illustrates that patterns of genetic diversity should be seen in the context of population histories and that future management decisions should take these insights into account. To address the conservation implications of our findings, we recommend prioritizing the maintenance of suitable habitats to facilitate population connectivity. Initiation of genetic restoration efforts and separately managing populations with unique evolutionary histories is crucial for preserving genetic diversity and promoting long-term population viability.

2.
Ecol Evol ; 14(2): e10982, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38362173

RESUMO

Social carnivores frequently live in fission-fusion societies, where individuals that share a common territory or home range may be found alone, in subgroups, or altogether. Absolute group size and subgroup size is expected to vary according to resource distribution, but for species that are susceptible to anthropogenic pressures, other factors may be important drivers. African lions (Panthera leo) are the only truly social felid and lion prides are characterized by fission-fusion dynamics with social groups frequently splitting and reforming, and subgroup membership can change continuously and frequently. The number of individuals in a group can be reflective of social, ecological, and anthropogenic conditions. This dynamic behavior makes understanding lion grouping patterns crucial for tailoring conservation measures. The evolution of group living in lions has been the topic of numerous studies, and we drew on these to formulate hypotheses relating to group size and subgroup size variation. Based on data collected from 199 lion groups across eight sites in Kenya, we found that group sizes were smaller when lions were closer to human settlements, suggesting that edge effects are impacting lions at a national scale. Smaller groups were also more likely when they were far from water, and were associated with very low and very high levels of non-tree vegetation. We found significant differences between the study sites, with the Maasai Mara having the largest groups (mean ± SD = 7.7 ± 4.7, range = 1-19), and Amboseli conservation area the smallest (4.3 ± 3.5, range = 1-14). While long-term studies within a single site are well suited to thoroughly differentiate between absolute group size and subgroup size, our study provides unique insight into the correlates of grouping patterns in a vulnerable species at a national scale.

3.
Animals (Basel) ; 12(15)2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35953975

RESUMO

In South Africa, lions are protected in national parks and smaller fenced reserves. Translocating lions between fenced reserves, whilst necessary to maintain genetic diversity, is disruptive and can impact survivorship and pride cohesion. Critical to translocation success is pride cohesion. White lions are a natural colour variant occurring in the Greater Kruger Park Region, where anthropogenic threats eliminated this population until reintroduction in 2006. Through social network analysis (SNA), the sociality of a released pride of captive-origin white and wild tawny lions was compared to two captive-origin and wild prides of tawny lions. Social interactions and pride dynamics were recorded for each pride. For all prides, cubs and subadults were central to the play network, while adults received the most social interactions. White and wild tawny adult males initiated more social interactions than captive-origin tawny males, whilst a keystone adult female was identified in each pride. For the constructed pride, social interactions were more evenly distributed, suggesting a high level of connectedness and cohesion. This is the first study to demonstrate that captive-origin white and wild tawny lions can form a socially functional pride, suggesting that white lions would survive in the wild in the absence of anthropogenic threats.

4.
Animals (Basel) ; 12(15)2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-35953993

RESUMO

White lions are a colour variant of the African lion Panthera leo melanochaita and disappeared from the wild due to anthropogenic factors until their reintroduction to the Greater Kruger Park Region of South Africa in 2006. Natural home range behaviour is an index of reintroduction success. Therefore, the home range and movement of a pride of reintroduced white lions and a constructed pride consisting of reintroduced white lions and translocated wild tawny lionesses in small, fenced reserves was assessed. GPS data from collared adults were collected for the white lion pride between 2010-2011 and 2018-2020 for the constructed pride. Home ranges were estimated using kernel density estimation and minimum convex polygon, with minimum daily distance tested for differences between sex, season, and pride. Home ranges were small and average daily movements restricted for both prides (white lion pride: 5.41 km2 and 10.44 ± 4.82 km; constructed pride: 5.50 km2, 11.37 ± 4.72 km) due to the small reserve size of 7 km2. There was no difference between prides for annual and seasonal home range size, male and female home ranges, minimum daily distance travelled, or habitat selection. White lions from both prides established territories and displayed natural home ranging behaviour, suggesting that their reintroduction was successful, in the absence of anthropogenic threats.

5.
Ecol Evol ; 12(4): e8857, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35475187

RESUMO

The fishing cat Prionailurus viverrinus is a wetland specialist species endemic to South and Southeast Asia. Nepal represents the northern limit of its biogeographic range, but comprehensive information on fishing cat distribution in Nepal is lacking. To assess their distribution, we compiled fishing cat occurrence records (n = 154) from Nepal, available in published literature and unpublished data (2009-2020). Bioclimatic and environmental variables associated with their occurrence were used to predict the fishing cat habitat suitability using MaxEnt modeling. Fishing cat habitat suitability was associated with elevation (152-302 m), precipitation of the warmest quarter, i.e., April-June (668-1014 mm), precipitation of the driest month (4-7 mm), and land cover (forest/grassland and wetland). The model predicted an area of 4.4% (6679 km2) of Nepal as potential habitat for the fishing cat. About two-thirds of the predicted potentially suitable habitat lies outside protected areas; however, a large part of the highly suitable habitat (67%) falls within protected areas. The predicted habitat suitability map serves as a reference for future investigation into fishing cat distribution as well as formulating and implementing effective conservation programs in Nepal. Fishing cat conservation initiatives should include habitats inside and outside the protected areas to ensure long-term survival. We recommend conservation of wetland sites, surveys of fishing cats in the identified potential habitats, and studying their genetic connectivity and population status.

6.
PLoS One ; 13(4): e0195373, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29672538

RESUMO

Wildlife attacks on humans and economic losses often result in reduced support of local communities for wildlife conservation. Information on spatial and temporal patterns of such losses in the highly affected areas contribute in designing and implementing effective mitigation measures. We analyzed the loss of humans, livestock and property caused by wildlife during 1998 to 2016, using victim family's reports to Chitwan National Park authorities and Buffer Zone User Committees. A total of 4,014 incidents were recorded including attacks on humans, livestock depredation, property damage and crop raiding caused by 12 wildlife species. In total >400,000 US dollar was paid to the victim families as a relief over the whole period. Most of the attacks on humans were caused by rhino, sloth bear, tiger, elephant, wild boar and leopard. A significantly higher number of conflict incidents caused by rhino and elephant were observed during full moon periods. An increase in the wildlife population did not coincide with an equal rise in conflict incidents reported. Underprivileged ethnic communities were attacked by wildlife more frequently than expected. Number of attacks on humans by carnivores and herbivores did not differ significantly. An insignificant decreasing trend of wildlife attacks on humans and livestock was observed with significant variation over the years. Tiger and leopard caused >90% of livestock depredation. Tigers killed both large (cattle and buffalo) and medium sized (goat, sheep, pig) livestock but leopard mostly killed medium sized livestock. Most (87%) of the livestock killing during 2012-2016 occurred within the stall but close (<500m) to the forest edge. Both the percentage of households with livestock and average holding has decreased over the years in buffer zone. Decreased forest dependency as well as conflict mitigation measures (electric and mesh wire fences) have contributed to keep the conflict incidents in control. Strengthening mitigation measures like construction of electric or mesh wire fences and predator-proof livestock corrals along with educating local communities about wildlife behavior and timely management of problem animals (man-eater tiger, rage elephant etc.) will contribute to reduce the conflict.


Assuntos
Animais Selvagens , Comportamento Animal , Parques Recreativos , Agricultura/economia , Animais , Conservação dos Recursos Naturais , Etnicidade , Florestas , Humanos , Modelos Lineares , Lua , Nepal , Pobreza , Estações do Ano , Análise Espaço-Temporal , Inquéritos e Questionários , Fatores de Tempo
7.
PLoS One ; 13(1): e0190898, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29385146

RESUMO

The global lion (Panthera leo) population decline is partly a result of retaliatory killing in response to livestock depredation. Nairobi National Park (NNP) is a small protected area in Kenya surrounded by a human-dominated landscape. Communities around the park use flashlights to deter lions from their livestock bomas. We investigated the response by lions to the installation of a LED flashlight technique during 2007-2016.We interviewed 80 owners of livestock bomas with flashlights (n = 43) and without (n = 37) flashlights in the surroundings of NNP and verified reported attacks on bomas against predation data over10 years. The frequency of attacks on bomas equipped with flashlights was significantly lower compared to bomas without flashlights. We also found that after flashlight installation at livestock bomas, lion attacks took place further away from the park edge, towards areas where bomas without flashlights were still present. With increased numbers of flashlight installations at bomas in recent years, we further noticed a shift from nocturnal to more diurnal predation incidences. Our study shows that the LED flashlight technique is effective in reducing nocturnal livestock predation at bomas by lions. Long term studies on the effects as well as expansion of this technique into other communities around NNP are recommended.


Assuntos
Luz , Leões , Gado , Comportamento Predatório , Animais , Conservação dos Recursos Naturais , Quênia
9.
Proc Natl Acad Sci U S A ; 114(3): 528-533, 2017 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-28028225

RESUMO

Establishing and maintaining protected areas (PAs) are key tools for biodiversity conservation. However, this approach is insufficient for many species, particularly those that are wide-ranging and sparse. The cheetah Acinonyx jubatus exemplifies such a species and faces extreme challenges to its survival. Here, we show that the global population is estimated at ∼7,100 individuals and confined to 9% of its historical distributional range. However, the majority of current range (77%) occurs outside of PAs, where the species faces multiple threats. Scenario modeling shows that, where growth rates are suppressed outside PAs, extinction rates increase rapidly as the proportion of population protected declines. Sensitivity analysis shows that growth rates within PAs have to be high if they are to compensate for declines outside. Susceptibility of cheetah to rapid decline is evidenced by recent rapid contraction in range, supporting an uplisting of the International Union for the Conservation of Nature (IUCN) Red List threat assessment to endangered. Our results are applicable to other protection-reliant species, which may be subject to systematic underestimation of threat when there is insufficient information outside PAs. Ultimately, conserving many of these species necessitates a paradigm shift in conservation toward a holistic approach that incentivizes protection and promotes sustainable human-wildlife coexistence across large multiple-use landscapes.


Assuntos
Acinonyx , Conservação dos Recursos Naturais , África , Animais , Ásia , Biodiversidade , Simulação por Computador , Extinção Biológica , Modelos Biológicos , Dinâmica Populacional/tendências , Fatores de Risco
11.
PLoS One ; 10(10): e0137975, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26466139

RESUMO

The evolutionary history of a species is key for understanding the taxonomy and for the design of effective management strategies for species conservation. The knowledge about the phylogenetic position of the lion (Panthera leo) in West/Central Africa is largely based on mitochondrial markers. Previous studies using mtDNA only have shown this region to hold a distinct evolutionary lineage. In addition, anthropogenic factors have led to a strong decline in West/Central African lion numbers, thus, the conservation value of these populations is particularly high. Here, we investigate whether autosomal markers are concordant with previously described phylogeographic patterns, and confirm the unique position of the West/Central African lion. Analysis of 20 microsatellites and 1,454 bp of the mitochondrial DNA in 16 lion populations representing the entire geographic range of the species found congruence in both types of markers, identifying four clusters: 1) West/Central Africa, 2) East Africa, 3) Southern Africa and 4) India. This is not in line with the current taxonomy, as defined by the IUCN, which only recognizes an African and an Asiatic subspecies. There are no indications that genetic diversity in West/Central Africa lions is lower than in either East or Southern Africa, however, given this genetic distinction and the recent declines of lion numbers in this region, we strongly recommend prioritization of conservation projects in West/Central Africa. As the current taxonomic nomenclature does not reflect the evolutionary history of the lion, we suggest that a taxonomic revision of the lion is warranted.


Assuntos
DNA Mitocondrial/genética , Marcadores Genéticos/genética , Leões/genética , África Central , África Ocidental , Animais , Evolução Biológica , Análise por Conglomerados , Conservação dos Recursos Naturais , Evolução Molecular , Variação Genética , Geografia , Repetições de Microssatélites/genética , Filogenia , Filogeografia , Análise de Componente Principal , Especificidade da Espécie
12.
Environ Manage ; 56(3): 684-94, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25971736

RESUMO

People who perceive economic benefits and enjoy unrestricted access to natural resources tend to support ecosystem conservation efforts. Our study explores whether this remains true in remnant patches of Afroalpine ecosystem in North Ethiopia, where communal land provides valuable natural resources for the local communities and also sustain small populations of the endangered Ethiopian wolf (Canis simensis). Questionnaires were designed to assess ecological and socio-economic characteristics of the livelihoods of the Amhara people living in Mount Abune Yosef and their attitudes toward Afroalpine and Ethiopian wolf conservation. Of the 120 households interviewed, selected randomly from across eight villages, 80 % benefited from natural resources by grazing their livestock and harvesting firewood and grasses. The majority (90 %) also suffered from livestock predation by Ethiopian wolves and common jackals (Canis aureus) and crop raiding by geladas (Theropithecus gelada), birds, and rodents, yet more than half reported a positive attitudes toward Ethiopian wolves (66 %). People with positive attitudes tended to live close to the communal land, to own more livestock, and to be unaffected by conflict. Many also recognized the need to protect the Afroalpine habitats of Abune Yosef (71 %), and this attitude predominated among the literate, households that owned land, had smaller herds and were further away. We discussed how people's attitudes were modulated by human-wildlife conflicts and by the benefits derived from the access to natural resources in communal land, and the implications for the conservation of Afroalpine ecosystem and the flagship Ethiopian wolf.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecossistema , Opinião Pública , Lobos/crescimento & desenvolvimento , Animais , Atitude , Conservação dos Recursos Naturais/estatística & dados numéricos , Etiópia , Humanos , Gado , Poaceae , Dinâmica Populacional , Comportamento Predatório , Inquéritos e Questionários
13.
PLoS One ; 9(1): e84674, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24416263

RESUMO

Lion populations have undergone a severe decline in West Africa. As baseline for conservation management, we assessed the group structure of lions in the Pendjari Biosphere Reserve in Benin. This reserve, composed of one National Park and two Hunting Zones, is part of the WAP transboundary complex of protected areas. Overall mean group size was 2.6±1.7 individuals (n = 296), it was significantly higher in the National Park (2.7±1.7, n = 168) than in the Hunting Zones (2.2±1.5, n = 128). Overall adult sex ratio was even, but significantly biased towards females (0.67) in the National Park and towards males (1.67) in the Hunting Zones. Our results suggest that the Pendjari lion population is affected by perturbations, such as trophy hunting.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Leões , Animais , Benin , Feminino , Masculino , Razão de Masculinidade
14.
PLoS One ; 8(2): e56235, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23437100

RESUMO

The African buffalo (Syncerus caffer) exhibits extreme morphological variability, which has led to controversies about the validity and taxonomic status of the various recognized subspecies. The present study aims to clarify these by inferring the pan-African spatial distribution of genetic diversity, using a comprehensive set of mitochondrial D-loop sequences from across the entire range of the species. All analyses converged on the existence of two distinct lineages, corresponding to a group encompassing West and Central African populations and a group encompassing East and Southern African populations. The former is currently assigned to two to three subspecies (S. c. nanus, S. c. brachyceros, S. c. aequinoctialis) and the latter to a separate subspecies (S. c. caffer). Forty-two per cent of the total amount of genetic diversity is explained by the between-lineage component, with one to seventeen female migrants per generation inferred as consistent with the isolation-with-migration model. The two lineages diverged between 145 000 to 449 000 years ago, with strong indications for a population expansion in both lineages, as revealed by coalescent-based analyses, summary statistics and a star-like topology of the haplotype network for the S. c. caffer lineage. A Bayesian analysis identified the most probable historical migration routes, with the Cape buffalo undertaking successive colonization events from Eastern toward Southern Africa. Furthermore, our analyses indicate that, in the West-Central African lineage, the forest ecophenotype may be a derived form of the savanna ecophenotype and not vice versa, as has previously been proposed. The African buffalo most likely expanded and diverged in the late to middle Pleistocene from an ancestral population located around the current-day Central African Republic, adapting morphologically to colonize new habitats, hence developing the variety of ecophenotypes observed today.


Assuntos
Búfalos/genética , Variação Genética , África , Animais , Teorema de Bayes , Búfalos/anatomia & histologia , DNA Mitocondrial/genética , Feminino , Genética Populacional , Geografia , Haplótipos/genética , Modelos Biológicos , Conformação de Ácido Nucleico , Filogenia , Probabilidade , Especificidade da Espécie
16.
C R Biol ; 326 Suppl 1: S112-8, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-14558459

RESUMO

The lion has historically probably been widespread at low densities in West and Central Africa, nowadays they are largely restricted to small isolated populations inside protected areas. The total number is probably between 1200 and 2700, the best possible guesstimate would be 1700. Mankind is the main cause for the suspected decline of lion populations, both inside and outside protected areas. Very little research has been done on West and Central African lions a few examples are summarized here. The international community is slowly becoming aware of threats to lions in the region and some initiatives for lion conservation have started.


Assuntos
Conservação dos Recursos Naturais/métodos , Leões , África Central , África Austral , África Ocidental , Animais , Biodiversidade , Conflito Psicológico , Bases de Dados Factuais , Meio Ambiente , Humanos , Densidade Demográfica , Dinâmica Populacional
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