Mallapur, A., Waran, N., Sinha, A. 2007. A note on enrichment for captive lion-tailed macaques (Macaca silenus). Applied Animal Behaviour Science 108(1-2), 191-195.

Two enrichment techniques were devised with the aim of reducing stress and improving welfare for captive lion-tailed macaques in an Indian zoo. In Study A, a log, cotton ropes and a feeding basket were added to the enclosures in different combinations to provide structural and feeding enrichment and were subsequently removed, while in Study B, singly-housed individuals were transferred to a large open-moated enclosure in which they were group-housed. The effects of these two enrichment techniques (social and physical) appeared to significantly improve the welfare of the study individuals by stimulating them to exhibit higher levels of natural behaviours along with the suppression of several abnormal behaviours.