To ensure and optimize husbandry conditions, zoo management and a high standard of animal welfare, understanding species-specific behavioral patterns is essential. While most research on ungulates focuses on daily activity budget and patterns, nocturnal behavior remains less studied. Therefore, we investigate the nocturnal activity of two endangered tapir species, the Lowland tapir (Tapirus terrestris) and the Malayan tapir (Tapirus indicus). While behavior studies on wild animals face great challenges, zoos offer a unique opportunity to analyze animals' behavior as they provide information on animals' life history, social patterns, husbandry conditions, and management plans. We analyzed 14 individuals over a total of 92 nights across six EAZA (European Association of Zoos and Aquaria) member zoos with respect to the three main behavior poses "Standing", "Lying - head up" and "Lying - head down". Our results show not only large differences between individuals, but also between nights within individuals. Furthermore, the analysis of lying cycles shows a tendency for Lowland tapirs to have longer lying cycles than Malayan tapirs, while Malayan tapirs enter the REM sleep position earlier than their relatives during a lying phase. However, sex-specific differences were not observed. The present analysis of nocturnal rhythms shows individual variability in both tapir species, although species-specific differences are hardly apparent, but do exist. The analysis of the resting cycles underlines that resting phases are interrupted several times by activity phases during the night. Implications for husbandry conditions and species conservation are discussed.
Kurzawe et al. (Thu,) studied this question.