Roux et al., 1983,
Species status generally accepted since original description, owing to chocolate-brownish breeding plumage with white face and throat, broad brown breastband, pink bill, and dark tip and cutting edges of upper mandible#R, but never entirely free of uncertainty owing to view that dark plumage of adults simply an extreme form of neoteny#R and problem that other characters evident in some representatives of D. antipodensis (hence no scoring attempted); moreover, recent molecular analysis indicates very close relationship (0·5% difference) with D. exulans#R, and correlation of plumage differences with latitude suggests an ecological response among populations of this and other taxa in exulans group (D. exulans, D. antipodensis and D. dabbenena) rather than intrinsic biological difference indicating lineages at levels of divergence associated with species rank#R#R. Another genetic analysis#R, however, claims a far higher level of divergence and argues that natal philopatry and at-sea distribution patterns establish this form as “a distinct, evolutionarily important population for which a unique biological history exists”; pending further clarification, status of present form as a species provisionally and precautionarily accepted here. Monotypic.
S Indian Ocean, breeding on Amsterdam I.
Food and feeding
Status and conservation
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