Bears in captivity are prone to develop stereotypic behaviours (S). While wild bears spend a considerable amount of time foraging every day (Carlstead et al. 1991), bears in captivity use limited time for feeding. This has been considered a causation of S (Mason 1991). In the present study, we showed that cheap environmenatl enrichment (EE) presentations can reduce levels of S as effective as expensive presentations.
One way of remedying S is to introduce EE. The benefits gained by EE are widely recognized by their positive effects on welfare. Few studies have, however, studied how to maximize the effect of EE. In order to gain the most benefit possible from EE, one should include beneficial strategies described in the literature (see Tarou & Bashaw 2007).
Animal responsiveness to EE is important (Young 2003); EE without external rewards is more subjected to habituation than EE with external rewards (Ings et al. 1997, Renner et al. 2000). Additionally, Murphy et al. (2003) stated that a reduced interest of an EE may recover if the EE item is withheld for a period of time. When Renner et al. (2000) after 14 days reintroduced EE to New World monkeys, the reinforcers had spontaneously recovered to similar levels as when they were first presented. Breaks between presentations may, thus, strengthen the responsiveness and allowing the same EE to maintain high rates of the rewarded behaviours.
The aim of this study was to investigate possibilities to maximize the effect of EE by comparing how a reduced frequency in EE presentation would differ to a high frequency regarding S and explorative behaviours, as both those behavioural groups are associated with animal welfare.
The bears i this study were subjected to two different treatments. EE was first presented for five consecutive days (ConsEE) and secondly, every alternative day for a total of five days (AltEE) to compare the effect of different frequencies of EE presentations. After each study, a post-EE period of behavioural sampling was conducted (ConsPost & AltPost respectively). This study was conducted on 14 (seven males, seven females) Sloth bears (Melursus ursinus).
Both treatments had a positive effect on levels of S (F4,48=5.115, P=0.002). AltEE did not, however, affect the levels of S long term. AltEE showed to have an effect on explorative behaviours, where ConsEE failed to do so (F=4,484.457, P<0.001). Both treatments showed a long term effect on the levels of exploration, thus, ConsEE showed higher effect after the EE was removed.
The results show, that although the frequency of EE presentations was reduced, similar, and for certain behaviours, more positive, results were observed for behavioural repertoires that are associated with increased welfare in captive bears. Both treatments showed to reduce levels of S, although presenting EE for five consecutive days had a longer positive effect. The reduction of S as well as the increase in explorative behaviours in both treatments may suggest that effectively present EE can enhance the captive animals’ welfare with lower costs.
Responsible for this page: Agneta Johansson
Last updated: 05/07/08