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Sensitive males: inbreeding depression in an endangered bird
Patricia Brekke1, Peter M Bennett, Jinliang Wang
1Institute of Zoology, Zoological Society of London, Regents Park, London NW1 4RY, UK. patricia.brekke@ioz.ac.uk
Proceedings. Biological Sciences
|July 2, 2010
Summary
Reintroducing threatened species can cause inbreeding depression, reducing offspring survival. This study on hihi birds reveals male embryos are more inbred, with inbreeding impacting males more severely.
Area of Science:
- Conservation Biology
- Population Genetics
- Avian Ecology
Background:
- Reintroduction programs aim to conserve threatened species but face controversy.
- Genetic bottlenecks can lead to inbreeding depression, impacting population viability.
- Few studies have rigorously assessed genetic consequences in wild-sourced reintroductions.
Purpose of the Study:
- To assess inbreeding and inbreeding depression in a reintroduced population of the endangered hihi (Notiomystis cincta).
- To investigate the genetic consequences of reintroduction for long-term population health.
Main Methods:
- Utilized molecular sexing techniques.
- Estimated marker-based inbreeding coefficients using 19 autosomal microsatellite loci.
- Analyzed genetic data from a free-living, reintroduced hihi population in New Zealand.
Main Results:
- Inbreeding was found to depress offspring survival rates.
- Male embryos exhibited higher average inbreeding coefficients compared to female embryos.
- Inbreeding depression effects were more pronounced in males, suggesting a male-biased impact.
- The studied population carries a significant genetic load.
Conclusions:
- Inbreeding negatively affects early life-history stages, particularly in male hihi embryos and nestlings.
- Male susceptibility may stem from dimorphism-driven faster growth and developmental stress.
- Findings highlight critical genetic considerations for threatened species reintroductions and long-term viability.
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