Social enrichment to reduce pacing in a solitary housed male lion-tailed macaque Macaca silenus

Abstract

Environmental enrichment is frequently used to improve the captive environment, aiming to enhance the quality of captive animal care. Social enrichment is considered to be the most effective form of enrichment for captive primates, particularly in the reduction of abnormal behaviours. This intervention was focused on reducing pacing behaviour exhibited by a singly-housed male lion-tailed macaque Macaca silenus by introducing another male. Data were collected using instantaneous scan sampling before and after the introduction of the second male. Data were then analysed using randomisation tests, which revealed that the introduction of the second male significantly (P<0.01) reduced the frequency of pacing in the first male macaque. This study has revealed that although the formation of all-male groups, particularly in lion-tailed macaques, is difficult it can also be beneficial, providing necessary social contact especially in individuals that are already familiar with one another.