Introduction

The decline of megaherbivores did not end with the termination of the Pleistocene. During the nineteenth century, expanding human settlements and continued hunting reduced Asian species to isolated populations, and ivory exploitation led to African elephant becoming rare over most of southern, eastern and western Africa. Following the advent of firearms, white rhino declined in southern Africa from a widespread and abundant species to the brink of extinction over the course of 60 years. In north-east Africa, white rhino recently suffered an even more dramatic decrease, from several thousand animals distributed through three countries in the early 1960s, to a remnant of about 15 restricted to one park in Zaire at the time of writing. Over much of Africa, remaining populations of elephant and black rhino are suffering steady attrition due to continuing human exploitation for ivory and horn. Javan rhino and Sumatran rhino were listed by the IUCN among the world's twelve most threatened animal species; Indian rhino, Asian elephant and black rhino are listed as endangered; and African elephant and white rhino, while currently safe numerically, remain vulnerable to poaching pressures.

Where populations of megaherbivores have been effectively protected, a contrasting conservation problem has arisen. Populations have increased to levels where they have induced vegetation changes such as to threaten the survival of other animal and plant species in these areas. As a result elephant, hippo and white rhino have been culled in the sanctuaries set aside for their protection.