Morepork

Identification

The morepork is 26 to 29 cm (10 to 11.5 in) long, with the female slightly larger than the male. Females are slightly heavier at 170–216 g (6.0–7.6 oz) compared with the male's 140–156 g (4.9–5.5 oz). The morepork has generally dark brown head and upperparts, with pale brown spots on head and neck and white markings on the rest of the upperparts, with a pale yellow-white supercilium (eyebrow), dark brown ear coverts, and buff cheeks. The eyes are yellow to golden-yellow. The feathers of the chin and throat are buff with dark brown shafts. The feathers of the underparts are mostly dark brown with buff and white spots and streaks, with the larger markings on the belly making it look paler overall. The upper tail is dark brown with lighter brown bars. The cere and bill is pale blue-grey with a black cutting edge. The feet are orange or yellow with blackish claws.<p>Young moreporks do not attain adult plumage properly until their third or fourth year. The tips of juvenile's feathers are white and fluffy, remnants of the nestlings' down. These are worn away over time, persisting longest on the head. The feathers of the head, neck, and underparts are fluffier overall. Their plumage is a darker and more greyish brown overall than that of adults.

Taxonomy

The morepork was formally described in 1788 by the German naturalist Johann Friedrich Gmelin in his revised and expanded edition of Carl Linnaeus's Systema Naturae. He placed it with the other owls in the genus Strix and coined the binomial name Strix novaeseelandiae. Gmelin based his description on the "New Zeeland owl" from Queen Charlotte Sound that had been described in 1781 by the English ornithologist John Latham in his multi-volume A General Synopsis of Birds. Latham obtained his information from Johann Reinhold Forster who had accompanied James Cook on his second voyage to the Pacific Ocean. The morepork is now one of 37 owls placed in the genus Ninox that was introduced in 1837 by English naturalist Brian Houghton Hodgson. "Morepork" has been designated the official name by the International Ornithological Committee.<p>Three subspecies are recognised:<p>Both Gerlof Fokko Mees and Ernst Mayr regarded the taxonomy of the boobook owl as extremely challenging, the latter remarking in 1943 that it was "one of the most difficult problems I have ever encountered". In his 1968 book Nightwatchmen of the Bush and Plain, Australian naturalist David Fleay observed that the boobooks from Tasmania more closely resembled those of New Zealand than those from mainland Australia, though he followed Mees in treating them as a single species. <p>Janette Norman and colleagues tested the cytochrome b DNA of three subspecies (as well as the powerful and rufous owls) to ascertain whether the closest relative was used in breeding with the last surviving female of the Norfolk boobook. They discovered that although the Norfolk boobook was similar in plumage to the Tasmanian boobook, it was genetically much closer to the New Zealand subspecies. In fact, the two were so close genetically that they considered whether the Norfolk boobook should be recognised as a separate taxon at all, although they conceded the two were easily distinguishable in appearance, so maintained the three as subspecies; the Tasmanian boobook only diverged by 2.7% from the other two, while the powerful and rufous owls diverged by 4.4% from each other. Leading from this, the Australian boobook was split from the Tasmanian boobook and morepork in volume 5 of the Handbook of the Birds of the World; however, several authors, including Les Christidis and Walter Boles, contested that the data had been misinterpreted from the Norman study, which had not sampled any Australian mainland boobooks at all. They treated the three taxa (southern, Tasmanian boobooks, and moreporks) as a single species.<p>Examining both morphological and genetic (cytochrome b) characters, Michael Wink and colleagues concluded that the Australian boobook was distinct from the morepork, as was the Tasmanian boobook, which is raised to species status as Ninox leucopsis. In 2022, the International Ornithological Congress reclassified the Tasmanian boobook and morepork as distinct species.

Scientific name

Ninox novaeseelandiae

Authority

(Gmelin, JF, 1788)

Order

Strigiformes

Family

Strigidae

Genus

Ninox

Range and habitat

In New Zealand's North Island, it is common from Rangaunu Harbour south to southern Taranaki and west of Tauranga, Lake Taupō, and Whanganui, as well as between Murupara and the Hangaroa River in the northeast, and southern Manawatū, Wellington, and Wairarapa in the south, and uncommon outside these areas. In the South Island, it is more common west of the Southern Alps, around Marlborough and in Southland. It is common on Stewart Island and offshore islands.<p>In New Zealand, it primarily inhabits forests dominated by Podocarpus, Nothofagus, Metrosideros, and other hardwoods, up to the alpine tree line. On Norfolk Island, it lives in forests of Norfolk Island pine (Araucaria heterophylla).

Migration

Resident species

Behavior

Migration pattern: Resident species.

Conservation

Population trend: stable.

Population trend

stable