Rinderpest virus originally caused major declines in buffalo numbers after 1890 but the virus has not caused declines since the 1960s (Dobson 1995; Dublin et al. 1990a; Rossiter et al. 1983; Sinclair et al. 2008), and indeed it is now globally extinct (Normille 2008). Bovine tuberculosis (Myobacterium bovis), although prevalent in South Africa (Cross et al. 2009), has not been found in Serengeti buffalo (Cleaveland et al. 2008; Sinclair 1977). Drought can be a major controlling factor and drought induced mortality occurred in 1993 causing approximately 40% mortality

in the buffalo population. This mortality was equally distributed across the ecosystem and therefore cannot be responsible VX-680 ic50 for the spatial patterns in recovery (Dublin et al.1990a; A. Sinclair unpublished data). While it is possible that other factors may contribute to the spatial learn more variation of buffalo recovery, the major controlling factors are likely to be food supply, natural predation and illegal hunting. We analyzed the impacts of these three factors—hunting, food supply and natural predation—using a spatial analysis to separate out their effects. Thus, human https://www.selleckchem.com/products/wh-4-023.html population density and rate of increase, which we show are related to hunting within the reserve (Campbell

and Hofer 1995; Hofer et al. 2000), are greatest in the west and northwest. In contrast, food limitation, which is a function of rainfall (Sinclair 1977), is most severe in the east and south, while predation is evenly spread over the buffalo range. The greatest food supply is in the north where rainfall is highest (Fig. 1). The next highest food levels are in the west, while

the lowest food supplies are Grape seed extract in the east (Sinclair 1977). During the 1960s, prior to the population collapse, these northern areas supported the highest densities of buffalo recorded in Africa, and in general Serengeti buffalo are limited by food and not by predation (Sinclair 1977). Fig. 1 The Serengeti ecosystem in Tanzania, East Africa includes the Serengeti National Park as a protected area, and the game reserves and conservations areas. These are the Ikorongo Game Reserve, Grumeti Game Reserve, Maswa Game Reserve, Ngorongoro and Loliondo Conservation Areas, which surround Serengeti National Park and have restrictions on settlement within their borders. The Serengeti National Park is divided up into zones (north, far west, centre, far east and south). Rainfall isohyets, showing the highest rainfall in the northwest and the lowest in the southeast. Rainfall data collected at local rainfall stations across the Serengeti ecosystem has been interpolated to produce the isohyets Materials and methods Study area The Serengeti-Mara ecosystem is located east of Lake Victoria and northwest of the Ngorongoro highlands and the Rift Valley (Fig. 1) and is described elsewhere (Sinclair and Arcese 1995b; Sinclair et al. 2007; Sinclair and Norton-Griffiths 1979).