Effects of changing housing conditions on mangabey behavior(Cercocebus atys): spatial density housing quality andnovelty effects

摘要

The separate influences of spatial density and housing quality on the behavior of captive animals are difficult to measure because the two factors are often intrinsically linked. Here, we recorded affiliative and agonistic behavior in adult sooty mangabeys in various housing situations, testing spatial density and housing quality changes separately (N=26 experienced spatial density changes; N=12 experienced housing quality changes). We varied spatial density by 50% while holding housing quality constant and we varied housing quality while holding spatial density constant (achieved by comparing two types of run-housing that varied in the amount of visual privacy and outdoor access). Each housing condition was one month in duration. Prior to collecting data in each housing condition, we evaluated the subjects’ initial responses to the change in housing environment during two-week novelty periods. Affiliative behavior did not change during the novelty periods. Agonistic behavior initially increased slightly when spatial density increased and it decreased significantly when spatial density decreased; it also decreased when subjects moved to housing that offered more visual privacy and outdoor space, indicating that the mangabeys were sensitive to these housing changes. After thenovelty periods, affiliative behavior increased under higher spatial density,but remained unchanged across housing quality conditions; agonistic behaviorremained unchanged across all conditions. Results suggest that a prolongedincrease in spatial density led the mangabeys to adopt a tension-reductioncoping strategy, in which the increase in affiliative behavior alleviates apresumed increase in social tension. Reducing visual privacy and choice did notaffect the mangabeys’ behavior, post-novelty period. Thus, like manyother primates, the mangabeys managed tension by flexibly adapting to changes intheir housing environment in ways that reduce the risk of severe aggression.This study highlights the importance of controlled behavioral studies infacilitating data-driven management decisions that promote animal welfare.