The species that are endangered in their wild habitats also need to be maintained as sustainable populations in captivity. The lion- tailed macaque (Macaca silenus) endemic to the Western ghats of India, is an endangered species. The captive breeding programmes for this species have been taken up in North America, Europe and India. However, the management practices for the captive popu- lation need to be standardized. We propose that an assessment of the biological potential of a captive population at any given time can help predict future population dynamics. Since system- atic data on the captive populations of the lion-tailed macaque in European institutions are available for the past several decades, we use those data to trace the development of the population in a historical perspective, and then use this perspective to develop a husbandry and population management manual for the lion- tailed macaque in captivity. We propose husbandry guidelines for individual groups, and also propose that each group should be considered a part of a metapopulation.

During a 5-yr study of lion-tailed macaques in their natural habitat, we found that: 1) most births occurred from January to April (70%) and from September to December (19%), showing a bimodal pattern with a major and a minor birth peak; 2) the period of peaks remained the same over 5 yr; and 3) a similar pattern of birth peaks occurred both in groups in large forest complexes that had overlapping home ranges with other groups and in single groups that were isolated in forest fragments in the same region but with similar ecological conditions. The results suggest more of a birth seasonality than mere breeding synchronization in the wild lion-tailed macaques. We also analyzed data on births in captivity in European Zoos for 10 yr. We observed no seasonality or peaks in births, and the pattern was the same over the years. Data on rainfall suggest that resource availability in the wild habitat may not be uniform throughout the year; hence, ecological factors may play an important role in determination of birth patterns in the natural habitats of lion-tailed macaques.

The lion-tailed macaque (Macaca silenus), endemic to rainforests of the Western Ghats; in southern India, is an endangered species. Most of its population now lives in fragmented pockets of rainforests. Considerable research has been carried out on its reproductive biology both on wild and captive populations in North America and Europe. We review studies carried out on birth seasonality, life-history parameters, and reproductive physiology and behaviour. The captive populations differ considerably from wild populations on several parameters of reproductive biology. Because of a low population turnover in this species due to a delayed age at first birth and long inter-birth intervals, and further degradation of its natural habitats, rapid population replenishment or augmentation is unlikely. This article shows that the study of reproductive biology may provide an important key to the conservation of this species. It also indicates that several aspects of reproductive biology of lion-tailed macaque still remain to be addressed.

We present data on sexual maturity in young hamadryas baboon males (Papio hamadryas hamadryas) and its reproductive consequences in a large captive baboon colony. Hamadryas baboons live in a multilevel social system, with one-male units (OMUs) as the smallest social entity. Male leaders of OMUs are believed to monopolize matings within their OMUs; hence mating is believed to be polygynous and monandrous. In a captive colony of hamadryas baboons, we found evidence that young males less than 4 years old fathered at least 2.5% of 121 offspring born subsequent to vasectomy of all adult males, and males aged 4-5 years fathered at least 16.5% of the offspring. Additional evidence that these young males are able to sire offspring came from a morphological comparison of sperm from hamadryas males of different ages. The sperm of a 48-month-old hamadryas baboon were morphologically indistinguishable from viable sperm from adult males, whereas sperm from a 45-month-old male showed some aberrations. If successful copulations by adolescent males constitute a regular pattern even in free-ranging hamadryas baboons, a hamadryas male's chances to reproduce would not be limited to his role as an OMU leader as previously assumed, and a male's reproductive career would consist of two phases: the adolescent phase, and the OMU leader male phase.