Perception of available space during chimpanzee introductions: Number of accessible areas is more important than enclosure size

Abstract

Restricting animals to different areas of their enclosure, for both brief and extended durations, is a key element of animal management practices. With such restrictions, available space decreases and the choices the animals can make are more limited, particularly in relation to social dynamics. When unfamiliar individuals are introduced to each other, group dynamics can be unpredictable and understanding space usage is important to facilitate successful introductions. We studied the behavioral, welfare-related responses of two groups of zoo-housed chimpanzees (n = 22) as they were introduced to each other and experienced a variety of enclosure restrictions and group composition changes. Our analysis of available space while controlling for chimpanzee density, found that arousal-related scratching and yawning decreased as the number of enclosure areas (separate rooms) available increased, whereas only yawning decreased as the amount of available space (m(2)) increased. Allogrooming, rubbing, and regurgitation/reingestion rates remained constant as both the number of enclosure areas and amount of space changed. Enclosure space is important to zoo-housed chimpanzees, but during introductions, a decrease in arousal-related scratching indicates that the number of accessible areas is more important than the total amount of space available, suggesting that it is important to provide modular enclosures that provide choice and flexible usage, to minimize the welfare impact of short- and long-term husbandry needs.

Effects of personality and rearing-history on the welfare of captive Asiatic lions (Panthera leo persica)

“…In this study we measured the evenness of enclosure use, which represents the functional space of the enclosure rather than available space. We found that small variations in enclosure sizes do not associate with significant shifts in behavioural welfare of Asiatic lions, which is in line with previous studies that place more importance on enclosure design (Tan et al, 2013), complexity and species-appropriateness than enclosure area (Rose & Robert, 2013;Herrelko, Buchanan-Smith & Vick, 2015;Neal Webb, Hau & Schapiro, 2018). The correlation between enclosure size and space usage bias was weak but positive, which means that increasing enclosure sizes were associated with higher zone-usage bias.…”

‘Regurgitation and reingestion’ (R/R) in great apes: a review of current knowledge

“…Malcolm et al, 1997;Wagaman et al, 1998;Thame et al, 2000), and so a 'social hypothesis' may fit for (some) non-human great apes as well. Baker and Easley (1996) found no relationship between R/R and social disturbance in their Chimpanzee study; similarly, Herrelko et al, (2015) found no change in R/R during the merging and introduction of two chimpanzee groups. In contrast, Miller & Tobey (2012) investigated R/R in 14 Bonobos housed at two zoos undergoing management changes in their group social structure.…”

“…In contrast, R/R has been documented to occur in at least some individual animals, across nearly all zoo-housed species of great apes, including Chimpanzees Pan troglodytes (e.g. Baker & Easley, 1996;Baker, 1997;Herrelko et al, 2015), Orangutans Pongo sp (e.g. Cassella et al, 2012), Bonobos Pan paniscus (Miller & Tobey, 2012), and Western lowland gorillas Gorilla gorilla gorilla (e.g.…”

Nest location preferences in zoo-housed orangutans

“…Individual NZP orangutans also showed significant preferences for particular rooms within buildings and locations within rooms. A preference for an off-exhibit room was detected for some individuals, confirming the importance of offering choice (Herrelko et al, 2015) to orangutans to use off-exhibit space in the late afternoon as they settle into their night nests.…”