Historical Development of Zoo Tapir (Tapirus ssp.) Survivorship.

Tapirs (Tapirus spp.) are large, long-lived herbivores native to Central and South America and Southeast Asia. All species are currently classified as Vulnerable (T. terrestris) or Endangered (other species) in the IUCN SSC Red List. With populations in the wild continuing to decline, the value of ex-situ populations as insurance populations increases. To assess demographic patterns, we evaluated juvenile and adult survivorship trends among the three tapir species (Tapirus bairdii, T. indicus, and T. terrestris) frequently kept in zoos from 1870 to 2024 using Cox proportional hazard models. Survivorship of Baird's tapirs was better than that of the two other species. Overall, both juvenile and adult survivorship has increased significantly. This was expected, given the developments in tapir husbandry over the past decades. Despite significant progress in husbandry practices, important areas for improvement remain, particularly in nutrition. Not all institutions provide optimal diets, which can affect health and longevity. In all three species, we document an increase in the proportion of old age-individuals and a decline in that of juveniles. As tapir survivorship increases and more individuals reach advanced ages, new challenges will arise in using controlled mortality to ensure viable populations.