Behavioral and Physical Development of Captive-Born Eastern Black Rhinoceros (Diceros bicornis michaeli) Calves

The birth of two eastern black rhinoceros (Diceros bicornis michaeli) calves (0.2) at the Blank Park Zoo in Des Moines, IA offered an opportunity to collect normative data for the first six months of calf development. Both calves successfully stood within 76 minutes of birth. Nursing first occurred at approximately 130 minutes. First defecation occurred within 1-2 days. Body weight increased by approximately 1.2 kg/day. Activity budgets for the first six months of the calves' lives revealed that they spent a substantial proportion of their time resting, followed by standing, walking, and eating, respectively. Nursing duration increased gradually over the study period. Calves spent the majority of their time throughout the first six months in close proximity to the cow. Interactions with inanimate features of the environment began early, and no clear developmental pattern was evident in the data. These data can serve as the initial entry in a public record of developmental information for this species and as a reference point for other zoos, assisting them in monitoring the health and proper development of black rhinoceros calves and maximizing their welfare.