Populations of African buffalo in the Masai Mara reserve in Kenya have crashed, due to domestic livestock grazing and global warming. Arup Shah / NPL / BBC

By Matt Walker Editor, BBC Nature
31 May 2011 Populations of wildlife species in the world-renowned Masai Mara reserve in Kenya have crashed in the past three decades, according to research published in the Journal of Zoology. Numbers of impala, warthog, giraffe, topi, and Coke’s hartebeest have declined by over 70%, say scientists. Even fewer survive beyond the reserve in the wider Mara, where buffalo and wild dogs have all but disappeared, while huge numbers of wildebeest no longer pass through the region on their epic migration. However, numbers of cattle grazing in the reserve have increased by more than 1100% per cent, although it is illegal for them to so do. This explosion in the numbers of domestic livestock grazing in the Mara region of south-west Kenya, including within the Masai Mara national reserve, is one of the principal reasons wildlife has disappeared, say the scientists who conducted the research. Dr Joseph Ogutu, a senior statistician in the Bioinformatics unit of the University of Hohenheim, Germany conducted the study with colleagues there and at the International Livestock Research Institute in Nairobi, Kenya. … “We were very surprised by what we found,” Dr Ogutu told the BBC. “The Mara has lost more than two thirds of its wildlife.” … The declines are particularly surprising, say the scientists, as they had expected animal populations to have recovered since 2000-2001. That is when major conservancy efforts, and an increase in local policing, began in an attempt to protect the wildlife there. “But to our great surprise, the extreme wildlife declines have continued unabated in the Mara,” says Dr Ogutu. “The great wildebeest migration now involves 64% fewer animals than it did in the early 1980s,” he adds. … There appear to be three main causes of these dramatic declines: the activities of poachers, changing land use patterns in ranches within the Mara, and an increase in the number and range of livestock held on these ranches. …

Wildlife ‘crash’ in the Mara region of Kenya, Africa