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Ex-situ avian sex skews: determinants and implications for conservation
Clancy A Hall1, Gabriel C Conroy1,2, Dominique A Potvin1,2
1School of Science and Engineering, University of the Sunshine Coast, Petrie, QLD, Australia.
Peerj
|April 22, 2025
Summary
Zoo-based avian conservation programs face challenges from sex skews. Male-biased sex ratios are more common in ex-situ collections than in the wild, impacting population stability.
Area of Science:
- Conservation Biology
- Avian Ecology
- Zoological Management
Background:
- Over half of avian species face global decline, increasing reliance on zoo-based recovery programs.
- Understanding breeding biology and environmental responses is crucial for conservation success.
- Sex skews, an imbalance of males to females, are an underlying cause of population decline in threatened species.
Purpose of the Study:
- To analyze sex ratio variation in global ex-situ avian collections.
- To identify factors influencing sex skews in zoo-based populations.
- To inform conservation management strategies for threatened birds.
Main Methods:
- Analysis of data from over 182,000 birds in global ex-situ collections.
- Interpretation of sex ratio variation based on avian orders, IUCN threat status, and housing location (within/outside natural range).
Main Results:
- Male-biased sex skews are more prevalent in ex-situ collections compared to wild populations.
- While sex ratios vary significantly between institutions, they approach parity globally.
- Threat status and housing outside natural range showed less significant variation in sex ratios.
Conclusions:
- Ex-situ management practices must become more efficient to address sex skews and ensure population stability.
- Findings have implications for the conservation management of threatened birds in integrated systems.
- Ex-situ populations can be optimized to maximize their conservation impact.
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