Spatial Distribution of Wildebeest in Serengeti National Park, Tanzania

Abstract

Serengeti wildebeest Connochaetes taurinus often come in contact with human activities which together with population growth, climate change and poverty tend to regulate wildebeest population. Since wildebeest distribution in relation to natural and man made changes is poorly understood, I examined ten GPS collared wildebeest from 2002 to 2004 to test for the spatial differences in distribution and movement rates. A pairwise comparison of different habitats computed using log-ratio of compositional analysis among GPS collared wildebeests indicated that open grassland, open woodland and wooded grassland were used significantly more frequently than other vegetation types. Habitat uses changed with seasons reflecting opportunistic feeding due to resources variability. Despite the relative potential of green grass and surface water migrating wildebeest avoided the western corridor during the migration. The pattern of space use was better explained by the movements which seemed to have increased even in the most frequently used habitats reflecting resource competition amongst wildebeest. Differences in daily movement rate between wildebeest sexes were better explained by the interaction between sexes and period of the day. Females appeared to be less active at night compared to males, especially during calving period (wet season), a strategy probably to minimize predation on less mobile neonates. Long-term data set from large sample sizes of wildebeest with detailed daily location GPS fixes is needed to enhance future management practices. Managers would benefits more from the study that compares foraging movements between resident and migratory subpopulations in the habitats which serves also as migratory corridors.

Key words: migration, movement, Serengeti, wildebeest, vegetation, human exploitation.