Population trends of resident wildebeest [Connochaetes taurinus hecki (Neumann)] and factors influencing them in the Masai Mara ecosystem, Kenya Original Research Article

Population trends of resident wildebeest (Connochaetes taurinus hecki (Neumann)) and factors influencing them in Masai Mara ecosystem between 1977 and 1997 were investigated. Population trends were analyzed using aerial census data collected through systematic reconnaissance flights. Aerial censuses pertaining to resident wildebeest populations (non-migratory) were identified from migratory populations through spatial analysis. Regression analysis was used for population trend analysis. The impact of land use changes on wildebeest population was analyzed by comparing changes in wildebeest densities in cropped and non-cropped areas. Relationship between population size and rainfall fluctuations was used to assess the influence of rainfall on trends. Comparison of cattle densities in cropped and non-cropped areas was used to get an insight into possible competition between cattle and wildebeest for food. The results show that resident wildebeest population in the Masai Mara ecosystem has declined from about 119,000 in 1977 to about 22,000 in 1997, an 81% decline. The decline is mainly attributed to loss of former resident wildebeest wet season grazing, calving and breeding ranges to agriculture. Rainfall fluctuations and possible competition between wildebeest and cattle during periods of limited food resources may have further contributed to the decline.