Reliably signalling a startling husbandry event improves welfare of zoo-housed capuchins (Sapajus apella)

Abstract

Animals kept in captivity are reliant on humans for their care and welfare. Enclosure design, and choice of group mates as well as routine husbandry events such as feeding, cleaning, and health care are in the hands of human keepers. It is therefore important to understand how external human-related husbandry events affect daily behaviour routines for animals, to help promote good welfare. Predictability (or lack thereof) of these routines can have profound effects on behaviours of captive animals. This study investigates whether providing a reliable predictable signal indicating entry into indoor brown capuchin (Sapajus apella) enclosures can increase welfare. All day focal follows of 12 zoo-housed capuchins were performed, recording behaviour in relation to husbandry events. The Baseline data show that unreliable sounds of door openings and closings outside the enclosure increase anxiety-related behaviours such as self-scratching, vigilance and jerky motions, and that the capuchins were startled by keepers entering the enclosure. A reliable signal (knocking) was subsequently introduced before enclosure entry and the monkeys given two weeks to associate the signal prior to Treatment condition data collection. The results indicate that the anxiety-related behaviours were reduced in the Treatment condition compared to Baseline frequencies. We conclude that making certain husbandry events reliable and predictable through the introduction of a unique signal can have a significant positive impact on the welfare of animals. Such an approach is not time consuming and costs nothing to implement, yet can result in significant advancements in animal welfare that can be implemented in a wide range of captive settings.