title: Sensitive males: inbreeding depression in an endangered bird.
abstract: Attempts to conserve threatened species by establishing new populations via reintroduction are controversial. Theory predicts that genetic bottlenecks result in increased mating between relatives and inbreeding depression. However, few studies of wild sourced reintroductions have carefully examined these genetic consequences. Our study assesses inbreeding and inbreeding depression in a free-living reintroduced population of an endangered New Zealand bird, the hihi (Notiomystis cincta). Using molecular sexing and marker-based inbreeding coefficients estimated from 19 autosomal microsatellite loci, we show that (i) inbreeding depresses offspring survival, (ii) male embryos are more inbred on average than female embryos, (iii) the effect of inbreeding depression is male-biased and (iv) this population has a substantial genetic load. Male susceptibility to inbreeding during embryo and nestling development may be due to size dimorphism, resulting in faster growth rates and more stressful development for male embryos and nestlings compared with females. This work highlights the effects of inbreeding at early life-history stages and the repercussions for the long-term population viability of threatened species.
authors.affiliation: Institute of Zoology, Zoological Society of London, Regents Park, London NW1 4RY, UK. patricia.brekke@ioz.ac.uk
authors.forename: Patricia
authors.initials: P
authors.lastname: Brekke
authors.forename: Peter M
authors.initials: PM
authors.lastname: Bennett
authors.forename: Jinliang
authors.initials: J
authors.lastname: Wang
authors.forename: Nathalie
authors.initials: N
authors.lastname: Pettorelli
authors.forename: John G
authors.initials: JG
authors.lastname: Ewen
mesh_terms: D000818:Animals; D056727:Endangered Species; D005260:Female; D040741:Genetic Load; D007178:Inbreeding; D008297:Male; D018895:Microsatellite Repeats / Q000235:genetics; D009520:New Zealand; D046109:Passeriformes / Q000196:embryology / Q000235:genetics / Q000502:physiology*; D012727:Sex Characteristics