Year: 2012
Type: dissertation
Abstract: Captive animals are frequently subject to imposed, uncontrollable stressors to which they \nrespond through behavioural flexibility, or, failing which, exhibit pathology. Chimpanzees \nprovide an intriguing model to examine how captive environments influence the responses of \nanimals to stress. My study investigates the responses of a group of chimpanzees to imposed \nstressors of captivity at the Johannesburg Zoo, South Africa. My study comprised four \ncomponents. Firstly, I examined the effects of spatial restriction on chimpanzee behaviour \nwith regard to an enclosure enlargement, testing several existing models of coping with \nspatial crowding and another model, based on the coping hypothesis of abnormal behaviour. \nBehavioural observations of the chimpanzees in their indoor and outdoor exhibits before, \nduring, immediately after and 10 weeks after the enclosure reconstruction revealed that the \nchimpanzees used tension-reduction and conflict-avoidance tactics as a means to cope with \nspatial crowding. Moreover, abnormal behaviour appears to provide an outlet for stress under \ncrowding. Secondly, I assessed the long-term effects of past spatial environments on the \nspace use and group spacing of the chimpanzees, five years after the enclosure change. \nThrough behavioural observations and mapping the locations of individuals, I found that the \nchimpanzees exhibit space-use bias and limited group spacing, contingent on the dimensions \nof the old enclosure that were not explained by factors such as social or thermal conditions \nand zoo visitor effects. I propose that the spacing patterns may be due to spatial learned \nhelplessness. Thirdly, I examined the effect of two social manipulations, mandated by zoo \nmanagement, on the behaviour and socio-dynamics of the chimpanzees. The chimpanzees \nresponded to social change through selective social interactions and non-social behavioural \nresponses suggest that removing an individual was less stressful than the merging of two \ngroups. Finally, I investigated the role of shade as a thermoregulatory resource for captive \nchimpanzees. Individuals used shade frequently despite observations taking place during the \naustral winter period, suggesting that shade is a valuable thermal resource for chimpanzees. \nIn conclusion, the chimpanzees responded to most imposed stressors (spatial crowding, social \nchange and thermal stress) through behavioural flexibility, implying successful coping, but \nfailed to cope with previous spatial restrictions, resulting in limited space-use behaviour.
Author: Luke Duncan
Language: English
Topic: Primate Behavior and Ecology
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W114270240