Environmental effects on the behavior of zoo-housed lions and tigers, with a case study of the effects of a visual barrier on pacing.

Tigers and lions in the wild are nocturnal nonhuman animals who may hunt and mate opportunistically during daylight hours. In captivity, they spend most time on exhibit sleeping or pacing. To better understand their activity budget, this study examined the daily behavior patterns of 2 Sumatran tigers and 3 African lions in different housings. The proportion of scans the large felids spent engaged in stereotypic pacing varied by time of day and environment. The tigers spent different amounts of time pacing when housed in different exhibits; the lions paced more in off-exhibit housing than when on exhibit. These differences suggest changes to the cats' immediate housing environment may decrease pacing but provide little insight into altering specifics. Carnivores' pacing relates to their inability to control sensory access to social partners. Both environments with increased pacing contained chain-link fencing. allowing uncontrolled sensory contact. Where the tigers paced, the study placed a visual barrier between one female and keepers' or conspecifics' cues. This did not significantly decrease pacing. However, the study suggests considering sensory access and environmental variables when designing environments for captive carnivores.