Sustainability of Captive Aye-Aye (Daubentonia madagascariensis) Populations: Breeding, Behavioural, Health and Genetic Perspectives

Abstract

This thesis examines the long-term sustainability of the global captive population of aye-ayes (Daubentonia madagascariensis), integrating health, genetics, breeding and behavioural perspectives into a novel, holistic framework for conservation management.
While captive sustainability has traditionally been defined by the retention of 90% genetic diversity over 100 years, this research reconceptualises sustainability encompassing genetic viability, demographic stability, behavioural competence and physical and psychological health. Given the species’ Endangered status, ongoing habitat loss in Madagascar, and evidence of low heterozygosity in wild populations, the role of ex situ management is increasingly significant.
Using Zoological Information Management System (ZIMS) records, non-ZIMS records, a keeper questionnaire and camera observations, this thesis evaluates four pillars of sustainability. The breeding study analyses 44 individuals across eight zoos to identify predictors of reproductive success and assess overall breeding viability. The behavioural study applies continuous focal sampling and a refined ethogram to evaluate activity budgets, enclosure use and the expression of species-typical behaviours. The health study examines veterinary and keeper records to identify prevalent conditions, treatment patterns and indicators of abnormal or stereotypic behaviour. Finally, a comprehensive pedigree is constructed to calculate genetic and demographic parameters, including founder representation, inbreeding coefficients, effective population size and population growth trends.
Findings indicate that although the captive population has grown since its foundation, reproductive success remains low, behavioural challenges persist, and demographic fragility is evident due to small population size. Genetic analyses highlight uneven founder representation and associated management implications. These lines of evidence collectively reveal the current aye-aye population is not sustainable.
By synthesising these findings, this thesis demonstrates that sustainability cannot be achieved through genetic management alone. Instead, welfare and conservation objectives must be integrated to ensure individuals both survive and thrive. Marrying individual need and genetic variation, this thesis provides a framework for investigating sustainability in zoo populations.

Date of Award	29 Jul 2026
Original language	English
Awarding Institution	University of Winchester
Supervisor	Lisa Riley (Supervisor), Gary Jones (Supervisor) & Hazel J Brown (Supervisor)