Environmental enrichment for zoo bears

Abstract

The high incidence of Stereotypie behaviors in zoo bears (van Keulen-Kromhout: International Zoo Yearbook 18:177-186, 1978) suggests that the environment of these animals lacks essential stimuli for guiding normal behavior. Three experiments investigated ways in which bear husbandry procedures can be altered to promote normal behavior. In experiments 1 and 2, honey-filled logs were given to a sloth (Melursus ursinas), American black (Ursus americanus), and brown bear (Ursus arctos) to determine 1) the role of food in stimulating investigatory behavior, 2) the rate of habituation to manipulable objects introduced into the exhibit, and 3) effects on locomotory behaviors. Results show specific and general habituation to the introduced objects that can be counteracted by refilling the logs with honey and by providing multiple logs in the exhibit. Investigatory activity directed toward honey-logs replaces pacing and walking in the sloth bear and is most effective in doing so when the log is novel. Experiment 3 examined the behavioral effects of feeding an American black bear in three different ways: 1) once daily in the den, 2) once daily with supplemental food from a mechanical feeder, and 3) once daily with food hidden in the exhibit in manipulatable objects. The latter method reduced Stereotypie pacing from a median of 150 min/day to 20 min/day ; the mechanical feeder method had no such effect. The results of a survey of 67 zoos concerning the diet and manner of feeding these three species of bears, as well as Asian black bears (Ursus thibetanus) are presented. Results are discussed with respect to the ways in which husbandry procedures can be improved to stimulate functional foraging and feeding behavior in confined bears.

Seasonal variation in stereotypic pacing in an American black bear Ursus americanus

“…In other bear species, frequent and varied feeding schemes in which the bears had to retrieve food or beg for it have also been anecdotally reported to reduce or be negatively correlated with stereotypy (polar bears Ursus arctos; Markowitz, 1978;Law & Boyle, 1986;van Keulen Kromhout, 1978). In an earlier experiment, it was shown that food snacks delivered automatically 6 times/day from a mechanical feeder device requiring no object manipulation for food retrieval, did not reduce this bear's pacing behaviour in the fall (Carlstead et al, 1991). Evidence for a behavioural need or preference to perform foraging and feeding behaviours has been reported in a number of different species (racoons, pigs, chickens, Breland and Breland, 1961;rats Carder and Berkowitz, 1970;rats and humans, Singh, 1970), and this has led to the observation that appetitive behaviours in some species may be self-reinforcing (Wiepkema, 1985;Dantzer, 1986;Hughes and Duncan, 1989).…”

“…Bears represent, perhaps, an extreme example of an animal "hardwired" to forage because of their large energy needs and seasonally variable food sources. In many captive environments with only one daily feeding of concentrated foods, the behavioural need to forage goes unmet and thus the high incidence of stereotypies in zoo bears (Carlstead et al, 1991). In such cases feeding methodology should be changed and exhibit spaces enriched with manipulatibie objects and substrate for hiding food.…”

Habituation to Auditory Stimuli by Captive African Elephants (Loxodonta africana)

“…Habituation to enrichment items has been observed in many captive animals, such as pigs (Sus spp. ), Western lowland gorillas (Gorilla gorilla gorilla), sloth bears (Melursus ursinus), and American black (Ursus americanus) and brown (Ursus arctos) bears [Anderson et al, 2010;Carlstead et al, 1991;Robbins and Margulis, 2014;Trickett et al, 2009]. Since the four elephants in the present study quickly habituated to the two auditory stimuli provided, it is plausible that captive elephants, in general, will habituate to auditory enrichment.…”

Frustrated Appetitive Foraging Behavior, Stereotypic Pacing, and Fecal Glucocorticoid Levels in Snow Leopards (Uncia uncia) in the Zurich Zoo

“…Supporting the hypothesis that stereotypic pacing found in captive carnivores is primarily caused by permanently frustrated appetitive foraging behavior (Carlstead, 1998), many other studies successfully provided a number of carnivore species with environmental enrichment related to feeding Carlstead, Seidensticker, & Baldwin, 1991;Forthman et al, 1992;Hartmann-Furter, 2000;Jenny & Schmid, 2002;Markowitz, Aday, & Gavazzi, 1995;Markowitz & LaForse, 1987;Shepherdson et al, 1993;Wechsler, 1994). Therefore, varying the spatial and temporal availability of food, as applied under our control-feeding regime, might have been stimulation enough to reduce-but not eliminate-stereotypic pacing compared with the conventional feeding regime, without using feeding boxes.…”