19 research outputs found
A genome-wide data assessment of the African lion (Panthera leo) population genetic structure and diversity in Tanzania
The African lion (Panthera leo), listed as a vulnerable species on the IUCN Red List of Threatened Species (Appendix II of CITES), is mainly impacted by indiscriminate killing and prey base depletion. Additionally, habitat loss by land degradation and conversion has led to the isolation of some subpopulations, potentially decreasing gene flow and increasing inbreeding depression risks. Genetic drift resulting from weakened connectivity between strongholds can affect the genetic health of the species. In the present study, we investigated the evolutionary history of the species at different spatiotemporal scales. Therefore, the mitochondrial cytochrome b gene (N = 128), 11 microsatellites (N = 103) and 9,103 SNPs (N = 66) were investigated in the present study, including a large sampling from Tanzania, which hosts the largest lion population among all African lion range countries. Our results add support that the species is structured into two lineages at the continental scale (West-Central vs East-Southern), underlining the importance of reviewing the taxonomic status of the African lion. Moreover, SNPs led to the identification of three lion clusters in Tanzania, whose geographical distributions are in the northern, southern and western regions. Furthermore, Tanzanian lion populations were shown to display good levels of genetic diversity with limited signs of inbreeding. However, their population sizes seem to have gradually decreased in recent decades. The highlighted Tanzanian African lion population genetic differentiation appears to have resulted from the combined effects of anthropogenic pressure and environmental/climatic factors, as further discussed
Erratum to: genetic structure of fragmented southern populations of African Cape buffalo (Syncerus caffer caffer)
Erratum to: genetic structure of fragmented southern populations of African Cape buffalo (Syncerus caffer caffer)
Genetic structure of fragmented southern populations of African Cape buffalo (Syncerus caffer caffer)
peer reviewedBackground
African wildlife experienced a reduction in population size and geographical distribution over the last millennium, particularly since the 19th century as a result of human demographic expansion, wildlife overexploitation, habitat degradation and cattle-borne diseases. In many areas, ungulate populations are now largely confined within a network of loosely connected protected areas. These metapopulations face gene flow restriction and run the risk of genetic diversity erosion. In this context, we assessed the “genetic health” of free ranging southern African Cape buffalo populations (S.c. caffer) and investigated the origins of their current genetic structure. The analyses were based on 264 samples from 6 southern African countries that were genotyped for 14 autosomal and 3 Y-chromosomal microsatellites.
Results
The analyses differentiated three significant genetic clusters, hereafter referred to as Northern (N), Central (C) and Southern (S) clusters. The results suggest that splitting of the N and C clusters occurred around 6000 to 8400 years ago. Both N and C clusters displayed high genetic diversity (mean allelic richness (Ar) of 7.217, average genetic diversity over loci of 0.594, mean private alleles (Pa) of 11), low differentiation, and an absence of an inbreeding depression signal (mean FIS = 0.037). The third (S) cluster, a tiny population enclosed within a small isolated protected area, likely originated from a more recent isolation and experienced genetic drift (FIS = 0.062, mean Ar = 6.160, Pa = 2). This study also highlighted the impact of translocations between clusters on the genetic structure of several African buffalo populations. Lower differentiation estimates were observed between C and N sampling localities that experienced translocation over the last century.
Conclusions
We showed that the current genetic structure of southern African Cape buffalo populations results from both ancient and recent processes. The splitting time of N and C clusters suggests that the current pattern results from human-induced factors and/or from the aridification process that occurred during the Holocene period. The more recent S cluster genetic drift probably results of processes that occurred over the last centuries (habitat fragmentation, diseases). Management practices of African buffalo populations should consider the micro-evolutionary changes highlighted in the present study
NESTING AND FEEDING TREE SELECTION IN THE ENDANGERED WHITE-BACKED WOODPECKER, DENDROCOPOS LEUCOTOS LILFORDI
Spatial properties of a forest buffalo herd and individual positioning as a response to environmental cues and social behaviour
Many animals aggregate into organized temporary or stable groups under the influence of biotic and abiotic factors, and some studies have shown the influence of habitat features on animal aggregation. This study, conducted from 2002 to 2004 in the Dzanga-Ndoki National Park, Central African Republic, studied a herd of forest buffaloes (Syncerus caffer nanus) to determine whether spatial aggregation patterns varied by season and habitat. Our results show that both habitat structure and season influenced spatial aggregation patterns. In particular, in open habitats such as clearings, the group covered a larger area when resting and was more rounded in shape compared to group properties noted in forest during the wet season. Moreover, forest buffaloes had a more aggregated spatial distribution when resting in clearings than when in the forest, and individual positions within the herd in the clearing habitat varied with age and sex. In the clearings, the adult male (n = 24) was generally, on most occasions, located in the centre of the herd (n = 20), and he was observed at the border only four times. In contrast, females (n = 80) occupied intermediate (n = 57), peripheral (n = 14) and central positions (n = 9) within the group. Juveniles (n = 77) also occurred in intermediate (n = 64) and peripheral positions (n = 13). Based on these results, we concluded that habitat characteristics and social behaviour can have relevant effects on the spatial distribution of animals within a group
Status and management of the endangered wild water buffalo ('Bubalis arnee') in Koshi Tappu Wildlife Reserve, Nepal
Asian wild water buffalo ('Bubalus arnee') are large ungulates, and the progenitors of all domestic water buffalo ('Bubalus bubalis'). There are two domestic types: the river buffalo of the Indian sub-continent and further west to the Balkans and Italy (Figure 24.1), and the swamp buffalo of Assam in the west, through Southeast Asia to the Yangtze Valley of China (Figure 24.2). All populations of 'Bubalus arnee' are considered Endangered (IUCN 2013), but in Nepal this species is protected by the National Parks and Wildlife Conservation Act (His Majesty's Government Ministry of Law and Justice 1977). There is evidence of buffaloes in the Indus Valley at least 5000 years ago (Nowak 1999; Lenstra & Bradley 1999). Although the historic range is uncertain, the species may have occurred from Mesopotamia to Indochina (Sinclair 1977). River and swamp buffalo were domesticated independently from different wild stocks that diverged anywhere from 10 000-15 000 (Barker et al. 1997) to over one million years ago (Amano 'et al'. 1994), but probably around 128 000-280 000 years ago (Kumar 'et al'. 2007a). River buffalo were domesticated around 6300 BP in the western region of the Indian subcontinent (Kumar 'et a'l. 2007b). Microsatellite and mtDNA diversity analyses (Yindee 2010; Zhang 'et al'. 2011) combined with archaeological evidence (Higham 2002) indicate domestication of the swamp buffalo in southern China/northern Indo-China about 2000 BC
Comparative analysis of forest buffalo grouping patterns in Central Africa
Presented at the 9th international wildlife ranching symposium: wildlife - the key to prosperity for rural communities, held on 12-16 September 2016 at Hotel Safari & the Safari Court, Windhoek, Namibia in conjuction with the IUCN 2nd African Buffalo Symposium.Understanding the social organization of elusive forest-dwelling ungulates may have important conservation and management implications. We present a comparison of grouping patterns in forest buffalo across different sites and through time in Central African rainforest. We examined five sites: Mbeli Bai and Bonye Bai (Nouabalé-Ndoki National Park, Republic of Congo), Dzanga Bai and Bai-Hokou (Dzanga-Ndoki National Park, C.A.R.) and Lopé-Okanda National Park (Gabon).Buffalo showed high site fidelity to open areas, including forest clearings. Forest buffalo herds (mean 12 ind. ± SD; range 3-24) were much smaller than records of savanna buffalo herds (mean 350 ind. ± SD; range 12-1500>), but also showed frequently fission-fusion patterns. Data from Mbeli Bai collected from 2012 to 2016confirm a stable presence of two buffalo herds (range 9-10 ind.) with occasional visits by lone individuals. Observations from Dzanga Bai over a period of 10 years (2006-2016) confirm the occurrence of only one buffalo herd (range 8-10ind.). In Bai-Hokou site, a single buffalo herd increased from 16 to 24 individuals during a three year period (2001-2004). Finally in Lopé National Park (a mosaic of savanna and forest fragments), the mean group size for 18 herds monitored from2002 to 2004 was 12±2 ind. (range of means=3–24). We analysed if herd size and herd stability are affected by clearing size, clearing type (e.g. marsh or land) and grass coverage across different sites and through time