Kenya's Masai Mara safari park generates over 13 to 15 per cent of Kenya's tourist revenue, 10 per cent of all its bed nights and over US$20 million in foreign exchange. But the park has not been effective in protecting wildlife. A 2001 report by Kenya's Regional Centre for Mapping of Resources for Development said wildlife in the park had declined by over 58 per cent in the past 20 years. Wildebeest numbers fell 81 per cent from 119,000 in 1977 to 22,000 in 1997. The Centre attributed this to changing land use outside the park, where grazing pasture has been turned into farmland. The park alone is too small to support its wildlife (Wildlife Dynamics: An Analysis of Changes in the Masai Mara Ecosystem in Kenya). In fact, only a quarter of the 'migratory corridors' used by wildlife in Kenya lie within national parks.

Overall, Kenyan wildlife declined by one third between 1977 and 1996. For example, Kenya's elephant population dropped by 85 percent, to approximately 20,000, between 1975 and 1990; and its rhinoceros population fell by 97 percent, to fewer than 500, during the same period.