The New Zealand storm-petrel (Pealeornis maoriana Mathews, 1932): first live capture and species assessment of an enigmatic seabird

The New Zealand storm-petrel Pealeornis maoriana Mathews, 1932 was described from 3 specimens collected in the 19th century. Since 1952 it has most commonly been considered a subspecies of Wilson’s storm-petrel Oceanites oceanicus exhibiting the ventrally streaked “Pealea” phenomenon. There had been no recorded sightings of the New Zealand storm-petrel in over 170 years before Jan 2003. Since then, observations off northern New Zealand of storm petrels believed to be this taxon have been made regularly during the austral summer. From observations and photographs, these birds appeared more similar to the New Zealand storm-petrel than to other storm petrel species occurring in the region. However, confirmation of their identity was not possible without capture. In Nov 2005 one was captured off Little Barrier Is, and 3 more were caught elsewhere in the Hauraki Gulf in Jan 2006. Analyses of detailed descriptions, photographs, and morphometric data of these birds provide conclusive evidence that they represent an extant population of the New Zealand storm-petrel. Our analyses of these data and comparison with the New Zealand storm-petrel museum specimens and 17 other Southern Hemisphere storm petrel taxa (subfamily Oceanitinae), lead us to conclude that this species is distinct.