Biology subjects

Lobora, A. L.

Publications and source records attributed to Lobora, A. L..

3 recordsLinked to original sources

bioRxiv2020

Density responses of lesser-studied carnivores to habitat and management strategies in southern Tanzanias Ruaha-Rungwa landscape

Compared to emblematic large carnivores, less charismatic or smaller carnivore species often receive little conservation attention, despite facing increasing anthropogenic pressure, and their status being poorly understood across much of their range. We employed systematic camera trapping and spatially explicit capture-recapture modelling to estimate variation in population density of serval, striped hyaena and aardwolf across the mixed-use Ruaha-Rungwa landscape in southern Tanzania. Three sites were selected as representative of different habitat types, management strategies, and levels of anthropogenic pressure: Ruaha National Parks core tourist area, dominated by Acacia-Commiphora bushlands and thickets; the Parks miombo woodland; and the neighbouring community-run MBOMIPA Wildlife Management Area, also covered in Acacia-Commiphora. Our results show that the Parks miombo woodlands supported a higher serval density than the core tourist area and Wildlife Management Area, with 5.56 [Standard Error = {+/-}2.45], 3.45 [{+/-}1.04] and 2.08 [{+/-}0.74] individuals per 100 km2, respectively. This variation is likely driven by precipitation, the abundance of apex predators, and the level of anthropogenic pressure. Striped hyaena were detected only in the Wildlife Management Area and at low density (1.36 [{+/-}0.5] individuals per 100 km2), potentially due to the location of the surveyed sites at the edge of the species global range, high densities of sympatric competitors and anthropogenic edge effects. Finally, aardwolf were captured in both the Parks core tourist area and the Wildlife Management Area, with a higher density in the Wildlife Management Area (13.25 [{+/-}2.48] versus 9.19 [{+/-}1.66] individuals per 100 km2), possibly as a result of lower intraguild predation and late fire outbreaks in the area surveyed. By shedding light on three understudied African carnivore species, this study highlights the importance of miombo woodland conservation and community-managed conservation, as well as the value of camera trap data to improve ecological knowledge of lesser-studied carnivores.

zoology↗

bioRxiv2017

Incipient signs of genetic differentiation among African elephant populations in fragmenting miombo ecosystems in south-western Tanzania

Habitat fragmentation plays a major role in the reduction of genetic diversity among wildlife populations. The African savannah elephant population of the Ruaha-Rungwa and Katavi-Rukwa ecosystems in south-western Tanzania, comprises one of the worlds largest remaining elephant populations, but is increasingly threatened by loss of connectivity and poaching for ivory. We investigate whether there are incipient signs of genetic isolation (loss of heterozygosity) within the younger cohort as a result of habitat loss between the two ecosystems. To investigate the genetic structure of populations, we compared the genotypes for 11 microsatellite loci in the western (n = 81 individuals from Katavi-Rukwa), central (n = 36 individuals from Lukwati and Piti), and eastern populations (n = 193, individuals from Ruaha-Rungwa). We found evidence of significant genetic differentiation among the three populations, but the levels were low, suggesting recent divergence. Furthermore, we identified weak isolation by distance, suggesting higher gene flow among nearer individuals with samples within 50km of each other being more genetically similar to one another than beyond. Although sample sizes were small, a further analysis of genetic differences across populations and in separate age classes revealed evidence of increasing genetic structure among younger age classes across the landscape. In a long-lived species with overlapping generations, it takes a long time to develop genetic substructure even when there are substantial obstacles to migration. Thus, in these recently fragmented populations, inbreeding (and the loss of heterozygosity) may be less of an immediate concern than demography (the loss of adults due to illegal hunting).

ecology↗

bioRxiv2017

Efficacy of land use designation in protecting habitat in the miombo woodlands: Insights from Tanzania

Loss of natural landscapes surrounding major conservation areas compromise their future and threaten long-term conservation. We evaluate the effectiveness of fully and lesser protected areas within Katavi-Rukwa and Ruaha-Rungwa ecosystems in south-western Tanzania to protecting natural landscapes within their boundaries over the past four decades. Using a time series of Landsat satellite imageries of September 1972, July 1990 and September 2015, we assess the extent to which natural habitat has been lost within and around these areas mainly through anthropogenic activities. We also test the viability of the remaining natural habitat to provide connectivity between the two ecosystems. Our analysis reveals that while fully protected areas remained intact over the past four decades, lesser protected areas lost a combined total area of about 5,984 km2 during that period which is about 17.5% of habitat available in 1972. We also find that about 3,380 km2 of natural habitat is still available for connectivity between the two ecosystems through Piti East and Rungwa South Open Areas. We recommend relevant authorities to establish conservation friendly village land use plans in all villages surrounding and between the two ecosystems to ensure long-term conservation of these ecosystems.

ecology↗