Behavioral and physiologic responses to environmental enrichment in the maned wolf (Chrysocyon brachyurus)

Abstract

The ex situ population of maned wolves is not self-sustaining due to poor reproduction, caused primarily by parental incompetence. Studies have shown that environmental enrichment can promote natural parental behaviors in zoo animals. The objective of this study was to determine the effects of environmental enrichment on behavioral and physiological responses of maned wolves. During an 8-week experimental period, daily behavior observations and fecal sample collection were conducted on four adult wolves (2.2) individually housed in environments without enrichment. After 2 weeks, the wolves were chronologically provided with 2-week intervals of hiding dead mice around the exhibit, no enrichment, and introduction of boomer balls. Responses of the wolves to enrichment were assessed based on activity levels and exploratory rates, as well as the level of corticoid metabolites in fecal samples collected daily throughout the study period. Providing wolves with environmental enrichment significantly increased exploratory behaviors (Po0.05), especially when mice were hidden in the enclosure. Fecal corticoid concentrations were increased during periods of enrichment in males (Po0.05), but not in females. Overall, there were no correlations between behavioral responses to enrichment and fecal corticoid levels. Behavioral results suggest that environmental enrichment elicits positive effects on the behavior of captive maned wolves. There is evidence suggesting that providing animals with ability to forage for food is a more effective enrichment strategy than introducing objects. There is need for a longer term study to determine the impact of environmental enrichment in this species.

Adrenal activity in maned wolves is higher on farmlands and park boundaries than within protected areas

“…These advances in understanding adrenal responsiveness to in ex situ [14,43] or in situ [9,31,34,47] environmental and seasonal changes have been made possible by the non-invasive assessment of glucocorticoids excreted in urine or feces. For carnivores, most steroid hormones, including glucocorticoids, are excreted in feces [15,32,33,62].…”

Comparison of two methods for glucocorticoid evaluation in maned wolves

“…Because the maned wolf is near threatened, it was not possible to work with a larger sample and perform a control study. As high inter-animal variation in GCM concentration were reported in similar studies , Chelini et al 2006, Cummings et al 2007), a 5-day baseline period was included, so that each animal could serve as its own control . For the same reason, it was not possible to assess the effect of the injection procedure itself by injecting other wolves with saline solution.…”

“…The steroid extraction method of Brown et al (1994) was used, as already described for maned wolves (Cummings et al 2007), with minor modiϐications. Aiming at the possibility of avoiding the costs and the spending of unnecessary time in lyophilisation, a pilot test was run, comparing a set of 12 wet and the corresponding 12 dried (lyophilized) extra samples.…”

Effects of Environmental Enrichment on the Social Behaviour of Javan Slow Loris, Nycticebus javanicus

“…Captive practitioners, zoo management, and animal researchers use environmental and behavioural enrichment to create a physical environment promoting psychological well-being of non-human primates (Shepherdson, 2007). Studies of environmental enrichment include: feeding enrichment, use of inanimate toys, varying substrates and group-housing arrangement depending on the animal's specific behavioural needs (Reinhardt et al, 1995;Brent & Belik, 1996;Vargas & Anderson, 1999;Kerridge, 2005;Maloney et al, 2006;Cummings et al, 2007;Dishman et al, 2009 (Brent & Belik, 1996); Lemurs (Kerridge, 2005;Maloney et al, 2006;Dishman et al, 2009); Marmosets (Robert et al, 1999); and Squirrel monkeys (Spring et al, 1997)], the information about the effect of environmental enrichment on slow lorises is scarce. Schulze & Meier (1995) used environmental enrichment in their study with the purpose of avoiding physical stress while observing the behaviour of Loris tardigradus nordicus, but the effect of the enrichment given was not recorded.…”