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Assessing Wildlife Distribution and Population Trends in the Greater Mara Ecosystem, Kenya: the synergistic effects of landscapes and threats

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As the biodiversity crisis continues there is a need to measure the loss of habitat and species. So far, investments in protected area (PA) or community based conservation initiatives have had limited success. In Kenya, protected areas constitute an impressive 12.3% of its designated land, yet the majority of these PAs are too small to maintain viable populations of threatened wildlife with large home ranges. The Greater Mara Ecosystem (GME) in southern Kenya covers 6,000km2, consisting of the Masai Mara National Reserve (MMNR) and 10 surrounding group ranches. In response to the need to simultaneously improve both wildlife conservation and local livelihood prospects alike, DICE, Friends of Conservation and the Massai developed, implemented and ran a community driven scout programme that was supported by the Darwin Initiative. From 2004-2006, some 74 Maasai scouts monitored the abundance and population trends of 26 wildlife species across the GME. This M.Sc. dissertation focused on four species, wild dog (Lycaon pictus), lion (Panthera leo), elephant (Loxondata africana) and zebra (Equus burchelli), that vary in their vulnerability to the different threat types across the GME. Fixed transect surveys were conducted to record focal species encounter rates thereby determining the population trends over two years. Non-fixed transects were also conducted to record encounter rates of threat types. Binary logistic regression analyses were performed to investigate the spatio-temporal physical variables and threat variables influencing focal species population trends and presence. The final models identified population trend and abundance patterns for elephant and lion populations, and abundance patterns only for wild dogs. Declines in elephant abundance were located in areas with lower retribution killings of crop pests and medium levels of bushmeat poaching. Declines in lion abundance were located in areas with medium threat levels in retribution of livestock predators and in areas closer to the MMNR border. Finally, wild dogs, which have suffered large scales declines over the past 30 years, were present in the wet and dry season in areas with high elevation and only the wet season in areas closer to rivers. This study aims to understand the variables affecting vulnerable species to enable future conservation programmes to the target key areas and reduce the decline of wildlife across the GME. The study also aims contribute to a wider understanding of patterns and causes of species decline across similar bioregions.
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... Elephants play an important ecological role in savannahs and forest ecosystems in maintaining suitable habitats for numerous animal species (Stephenson, 2007). Their habit of stripping bark from trees and pulling down trees to access fodder modifies vegetation dynamics and plays a fundamental role in the creation of savannah-woodland mosaics (Richmond, 2006). As pointed out by Osborne (2012), the loss of elephant habitat and subsequent home range in priority areas is a cause for concern and is caused by agricultural expansion into elephant habitat. ...
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