African elephants ( Loxodonta africana ) and black rhinoceroses ( Diceros bicornis ) are charismatic mammals that help draw visitors into zoological institutions. Because they evolved in the same habitat utilizing similar food resources, the two species have many physiological similarities yet behaviorally remain very different. Limitations of the zoo environment, such as constraints on exhibit size, social complexity, and behavior, may be associated with health and behavioral problems seen in both species and thought to be exacerbated in northern, temperate climates. The purpose of this study was to determine how the behavioral patterns of two large-bodied African ungulate species were affected by seasonal changes in a northern climate zoo. The behavior of three African elephants and three black rhinoceroses was observed for one year at Cleveland Metroparks Zoo. We found average resting levels of African elephants and black rhinos were similar to expected values based on data from wild and captive studies. Both species adapted their behavior to cope with high temperatures and increased sun exposure. Increased time spent inside during winter months was associated with decreased investigatory behaviors in elephants and decreased locomotion in rhinos. To increase species-typical behaviors, exhibits should include substrates for dusting, mud wallows, shade structures, and resting sites for all individuals. Time spent feeding may be increased through natural food items such as browse. Indoor exhibits should include environmental variation, enrichment, and adequate space so as to encourage these behaviors. Physiological and health measurements might be measured to determine sufficient levels of exercise for zoo-housed elephants and rhinos.
