Fecal Glucocorticoid Metabolite Concentration as a Tool for Assessing Impacts of Interventions in Humboldt Penguins (Spheniscus humboldti)

Shangzhe Xie,Todd J Mcwhorter

doi:10.3390/birds2010007

Abstract

It is currently unknown if current guidelines for collecting and interpreting blood corticosterone in flying birds can be extrapolated to penguins. It is also difficult to collect blood quickly without causing stress to a penguin. Therefore, immunoreactive fecal glucocorticoid metabolites (FGCMs) may be the most practical and minimally invasive way of monitoring the stress levels of penguins. This study investigated the reliability of FGCMs for monitoring stress levels in captive Humboldt Penguins (Spheniscus humboldti) at Jurong Bird Park, Singapore. Humboldt Penguin feces were randomly sampled and pooled from the exhibit for 2 months. The penguins were restrained and transported on three separate occasions to simulate stressful events. The feces were analyzed using an enzyme immunoassay to measure corticosterone levels. There were significant increases lasting 3 to 7 days in the FGCM levels after a stressful event. This method was then used to test whether accelerometer vests used for behavior quantification caused stress responses in these birds. There was no significant difference in FGCMs between time periods with and without the accelerometer vests. The results indicated that FGCMs can be an accurate indication of capture-, restraint-, and transport-related stress in Humboldt Penguins, and that accelerometer vests do not appear to cause stress.

Highlights

Humboldt Penguins (Spheniscus humboldti) are found in coastal Peru, Chile, Colombia, and Ecuador [1]
fecal glucocorticoid metabolites (FGCMs) levels increased above baseline + 2SD 1 day after each stressful event and returned to below baseline + 2SD within 3 to 7 days of the event
The results supported our hypothesis that stress caused by capture and transport would result in an increase in FGCM levels

Summary

Introduction

Humboldt Penguins (Spheniscus humboldti) are found in coastal Peru, Chile, Colombia, and Ecuador [1]. The species is endemic to the Humboldt Current Region, restricted to cool, nutrient-rich waters [2], and has been listed as a vulnerable species by the International. Humboldt Penguins are commonly exhibited in zoos and aquaria around. Birds 2021, 2 the world, and it is important to ensure good welfare in captivity. Birds in captivity are potentially exposed to a variety of stressors, such as visitors or inclement weather. Minimally invasive, and efficient methods of monitoring stress and discomfort in animals held in captivity is of increasing scientific interest due to the increase in public concern and ethical issues regarding the welfare of captive animals [4]

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Results

Conclusion