The Scoop on Honey Badger Poop: Validation of a Non-Invasive Method for Assessing Physiological Responses in...

Captive honey badgers (Mellivora capensis) are routinely exposed to environmental and husbandry-related stressors that differ markedly from their natural conditions; however, physiological welfare assessments in this species remain limited. This study aimed to validate a non-invasive approach to evaluate stress-related fecal glucocorticoid metabolite (fGCM) concentrations and individual responses to visitors and other environmental stressors in two zoo-housed individuals. Five enzyme immunoassays (EIAs) were assessed for suitability using routine veterinary examinations as a presumed biological stressor. The 5α-pregnane-3β,11β,21-triol-20-one EIA proved most suitable, detecting increases in fGCM concentrations of 251% and 127% in the male and female, respectively. This EIA also demonstrated immunoreactive fGCM stability for up to 16 days post-defecation under ambient conditions, supporting application to field surveys where immediate sample collection is not always feasible. While visitor numbers showed no correlation with changes in fGCM concentrations, both individuals displayed persistent stereotypic behaviors, suggesting that they had habituated to human presence but remained responsive to other environmental disturbances. Longitudinal profiles revealed substantial individual variation in fGCM responses, with baseline concentrations being higher in the male. Elevations in fGCM concentrations (up to 945%) were associated with construction noise, neighboring animal introductions, and high visitor presence during special events. This validated method provides a reliable tool for monitoring stress physiology in captive honey badgers, with an application for evidence-based improvements in zoo husbandry and future application in free-ranging individuals.