Severe decline of large birds in the Northern Sahel of West Africa: a long-term assessment

摘要

The current status of most West African birds is little known and may change quickly with increasing human population pressure and agriculture, road, tourism, hunting and mining developments. Following documented declines of raptors in Sudan and the Southern Sahel zones, I compared the number of birds counted along the same eight extensive transect counts in 1971-1973 (3,703 km) and 2004 (3,688 kin) in and steppes, acacia woodlands and desert mountains of northern Mali and Niger (Adrar des Iforhas, Air, Tenere). The once widespread Ostrich Struthio camelus is now extinct west of Chad. No Arabian Ardeotis arabs and Nubian Bustards Neotis nuba were seen in 2004 (216 in 1970s) nor any Ruppell's Griffon Gyps rueppellii and Lappet-faced Vultures Torgos tracheliotus (114 and 96 respectively recorded in the 1970s). From Adrar to Tenere, just one Egyptian Vulture Neophron perenopterus was recorded in 2004 (vs 75 in 1970s), but it was still common in the oases of Kawar (27 vs 38). These data are exploratory and the current status of the species involved should be further documented. Nevertheless, they are a serious warning about the future of several taxa. Overhunting, aggravated by overgrazing and degradation of acacia woodlands ire obvious causes of the collapse of Ostrich and bustards. The near-extinction of wild ungulates, intensified use of cattle, increased disturbance and poisoning of predators may have been critical in the dramatic decline of vultures. An effective bunting ban, updates on the status of threatened species, reintroduction of Ostrich, enforcement of existing nature reserves and design of a new one in northern Mali are among the most urgent steps to take if the large birds of the vast subdesert areas of West Africa are to be conserved.