Captive propagation of threatened primates - the example of the Lion-tailed Macaque Macaca silenus

Abstract

Many conservation-oriented breeding programs are not likely to reach their goal of establishing self-sustaining populations. Some zoo biologists propagate to reconsider zoo-based conservation policies and strategies. The Lion-tailed Macaque is a flagship species for in situ conservation and a high priority species in captive propagation. This article reviews the captive management history of the Lion-tailed Macaque, identifies management patterns that might have negatively influenced the development of the programs, and proposes to use this analysis to initiate a new management perspective. In the North American captive Lion-tailed Macaque population under the Species Survival Plan (SSP), the strong reduction in population size and group sizes due to space problems might have contributed to a decrease in population viability. The population over two decades has declined from almost 300 to less than 100 individuals. In the European population under the European Endangered Species Program (EEP), population size was not limited and larger groups were advocated. The population grew slowly but steadily to a present size of more than 350 individuals over about 23 years. The effective population size has remained low in both SSP and EEP populations. A general conceptual framework that focuses on individuals and their phenotypes for in situ and ex situ conservation recently developed by field conservationists is briefly introduced. It is used to suggest improvements in the management of the Lion-tailed Macaque. It is concluded that the size and structure of a breeding population is to be decided so as to provide conditions and materials for successful reproduction rather than by the available zoo space only. For this, large groups and populations with representation of all age-sex classes are advocated. This would result in a further reduction in the number of species kept in zoos. It is indicated that zoo biology needs to develop new concepts that include a large spectrum of concepts of biology and knowledge about the adaptive potential of animal species under altered and fragmented conditions.