Movements of the migratory wildebeest population in the Serengeti area between 1960 and 1973

Abstract

Summary Data on the monthly distributions of the Serengeti migratory wildebeest population between June 1960 and May 1973 have been analysed. It has been shown that the population performs an annual migration, spending the wet season on the Serengeti plains, then moving west towards Lake Victoria at the beginning of the dry season, and later north to the northern extension of the Serengeti National Park or into the Masai Mara Game Reserve in Kenya. The wildebeest return to the plains as soon as the rain begins, but if this is delayed they may move south‐west from the northern areas into the corridor first. Annual differences in the pattern of the migration can be correlated with differences in rainfall. The rainfall affects particularly the timing of the movements of the wildebeest on and off the plains, and the extent to which they utilize the northern areas. A large increase in the size of the population over the years studied has resulted in a greater utilization of the northern areas. It has been shown that about half the total range of the wildebeest population is outside the boundaries of the Serengeti National Park, and it is therefore important that these areas should be protected if such a large population is to survive.

Competition, predation, and migration: individual choice patterns of Serengeti migrants captured by hierarchical models

“…The study of movement trajectories of individual animals enables us to distinguish the specific landscape variables to which migratory animals are responding, when these variables may be important, and if different migratory species are reacting to the same environmental conditions (Patterson et al 2008). Although the general pattern of the Serengeti wildebeest and zebra migrations have been known for a long time (Pearsall 1959, Grzimek and Grzimek 1960, Watson 1967, Pennycuick 1975, and more recent studies have identified the drivers of these migrations at the population level (Boone et al 2006, Holdo et al 2009bHopcraft et al, in press), the specific cues to which individual animals are responding, until now, had not been empirically identified. Understanding how animals respond to local environmental conditions provides clues about the drivers of these large-scale annual migrations and the role of these in population dynamics.…”

“…Mongollian gazelle (Procapra gutturosa) also move in relation to latitudinal gradients of frost, but their movements tend be more variable than those of saiga, despite living in similar environments (Ito et al 2006, Olson et al 2010, Mueller et al 2011. Wildebeest (Connochaetes taurinus) in the Serengeti migrate over an opposing rainfall and soil fertility gradient (Holdo et al 2009b) where high soil fertility areas attract large herds during the wet season and high-rainfall areas are a refuge during the dry season (Pennycuick 1975, Maddock 1979, Boone et al 2006. However, it is not well understood how individual animals weigh the costs and the benefits of moving in response to food and predation in such a way that leads to an annual migration.…”

Fire history and management as determinant of patch selection by foraging herbivores in western Serengeti, Tanzania

“…The average annual rainfall varies from 600 mm per year on the south-east plains to around 1100 per year in the north (Pennycuick 1975). Temperature in the western Serengeti is higher than in the eastern and it may rise above 36…”

Assessment of distribution patterns for the grey kangaroo within southern Queensland : an application and appraisal of faecal pellet counts and aerial survey for the study of grey kangaroo density and distribution

“…The relationship has been documented for non migratory animals utilizing similar climatic regimes to that of the grey kangaroo (e.g. Klingel, 1969;Bourliere and Hadley, 1970;Simpson, 1972;Western, 1975;Pennycuick, 1975;Kutilek, 1979; Afolayan and Ajayi, 1980;Laurie, 1982). With regard to other macropods, forage availability, notably green pick from perennial grasses, has been found to exert a major influence on the distribution of red kangaroos (Frith, 1964;Chippendale, 1962Chippendale, , 1968Newsome, 1965aNewsome, , b, 1971aNewsome, , 1975Frith and Calaby, 1969;Bailey, 1971;Denny, 1979, Low et ai., 1981 and euros (Ealey, 1967a).…”

“…The relationship has been documented for non migratory animals utilizing similar climatic regimes to that of the grey kangaroo (e.g. Klingel, 1969; Bourliere and Hadley, 1970;Simpson, 1972;Western, 1975;Pennycuick, 1975 …”