Conservation of Isla Socorro, Mexico:: The impact of domestic sheep on the native plant communities

The: impact of feral sheep on the natural resources at Isla Socorro, thr largest of the four Pacific islands that constitute the Revillagigedo Archipelago Biosphere Reserve: off the northwest coast of Mexico, has the potential to severly damage this ecosystem. The feral sheep population, which is concentrated on the southern part of the island, was determined through surveys during 1988 and 1990. Direct counts indicate the present population, size to he well over the carrying capacity of the island's ecosystems. As a result of thr high population density and the overgrazing, there is severe erosion on 30% of the island. If the feral sheep of Isla Socorro are not totally removed in the very near future, this Biosphere Reserve and the world's natural heritage will likely lost all endemic species on this island.