Differences in Mother–Infant Bond and Social Behavior of African Elephant Calves Living In Situ and Ex Situ

SIMPLE SUMMARY: In the wild, African elephant calves must stay close to their mothers and the family unit as the African environment holds many threats. African elephant calves in zoos are raised in a protected environment. Therefore, we hypothesize that calves ex situ hold bigger distances and behave differently than in situ. Additionally, those differences are likely to increase with further zoo generations. This study used ethological research methods to compare the mother–calf bond of African elephant calves in situ and ex situ (first and second generation). The results showed that ex situ living calves of both generations maintain greater distances to their mothers and show a wider variation (positive and negative) in behavior than in situ. The detected differences indicate that calves ex situ can behave more freely as they are in a protected environment. Therefore, they can develop faster than in the wild, which agrees with similar findings on African elephant calf development and adult African elephants. The hypothesis that differences between in situ and ex situ increase with the zoo generations could not be verified. Hence, modifications in behavior under different environmental selection pressures may be adaptive. ABSTRACT: African zoo elephants live in safe environments with sufficient resources, are protected from threats, and have their health and body conditions cared for. Calves ex situ undergo the same developmental stages as in situ and are raised by the whole family unit. However, due to environmental differences, there might be behavioral modifications between calves in situ and ex situ. We hypothesize that these differences increase with ongoing generations. This ethological study compares social and general behavior and the distance calves kept to their mothers’ between calves of the first (F1) and second (F2) zoo generation and the wild. Using ethological methods, data were collected for ~90 in situ calves and 16 ex situ (8 F1, 8 F2) between the ages of 0.5 to 4 years (120 observation hours per group). Results showed that in situ calves spent significantly more time close to mothers than the F1 and the F2 zoo generations (F1/in situ: p = <0.001; F2/in situ: p = 0.007). The behaviors of eating, drinking, trunk movement, washing, and affiliative behaviors showed significant differences between in situ and ex situ calves. The amount and distribution of affiliative and agonistic behavior initiated and received by calves was displayed with a greater variety ex situ. Ex situ calves not only performed affiliative but, in contrast to the in situ, also agonistic behavior (F1/in situ: initiated p = 0.002, received p = 0.010; F2/in situ: initiated p = 0.050, received p = 0.037). The comparison of zoo generations suggests that differences did not increase with the generation. The more casual binding between mothers and offspring in zoos and the age-dependent improvement of social behavior of zoo-born calves are seen as a result of elephants’ adaptation to secure zoo conditions. The results of this study agree with the faster development of ex situ African elephants, like earlier puberty and more frequent breeding patterns, as known from the literature.