For years, biologists in Africa have known that large mammals - including antelopes and their predators - were disappearing outside reserves. Now a raft of studies, published in the September 2007 issue of the African Journal of Ecology, show that we have moved beyond this. We are losing species from national parks, bastion of biodiversity conservation. Worryingly, this includes the continent's crown jewels such as Tanzania's Serengeti National Park.
Tim Caro (University of California, Davis, USA) and Paul Scholte (Leiden University, the Netherlands) review a range of wildlife inventories covering the entire Africa continent. Only recently, long term datasets of extensive areas have been mined using sophisticated statistical methods. In addition, population changes have now been traced within a single reserve across considerable time frames. These studies focus on antelopes that are relatively easy to count. Most are delicious to eat...
Caro and Scholte suspect that the documented declines represent only the tip of the iceberg. "Antelope populations have been poorly surveyed, and with the notable exceptions of the African Journal of Ecology articles, have failed to present quantitative information. What the new data show, is even relatively well-organised protected areas cannot be relied on as long-lasting conservation tools".
"The causes of the large mammal declines are principally anthropogenic. Many parks are subject to the ravaging impact of illegal hunters. In West-Central Africa, this bushmeat hunting used to cover local consumption only, now it includes tables in far off cities that extend to London and Paris. Then there are reserves in which human encroachment is the driving force, whereas in reserves too small to harbour wildlife populations year-round, natural and anthropogenic causes operate in concert".
Caro and Scholte are cautious in formulating solutions, most of which impact poor people. "The idea of setting aside large tracts of land is outmoded by land-use change and demographics. Increased patrols, equipment and incentives for park guards, in tandem with community outreach programs, will go some way to stop poaching; whereas opposition to land greedy development schemes may halt encroachment. But ultimately we may have to get used to faunal relaxation in Africa's famous reserves leaving a continent containing isolated pockets of large mammal diversity living at low population sizes. Just like Europe".