Cormorano bianconero minore

Identificazione

The little pied cormorant is a small cormorant measuring 56–58 cm (22–23 in) with a shorter 3 cm (1.2 in) bill and longer tail than the little black cormorant; it has a small black crest. It is found in two morphs in New Zealand. Subspecies melanoleucos and brevicauda are found only in a pied morph, black (with a slight green tinge) above and white beneath. This is also found in subspecies brevirostris, but in this form the melanistic morph is much more common. In this form the entire plumage is black with a greenish tinge except for the sides of the head, chin, throat and upper neck; the bill is yellow with black on top. Intermediate forms are also found.<p>The pied form is glossy black above with white face, underparts and thighs. The bill and bare skin around the face are yellow. In both forms the legs and feet are black. The pied form is rare in New Zealand, and is most common there in Northland, where it makes up one in every four birds or so.<p>Chicks have dark brown down, with pied morph having patches of paler down. Immature birds are a dull blackish brown, with pied morph birds having paler underparts.<p>The little pied cormorant makes a low cooing during courtship.<p>Similar species include the black-faced cormorant (slightly larger) and the Australian pied cormorant (substantially larger).

Tassonomia

The species is known as the little pied cormorant in Australia, and as the little shag or by the Māori name of kawaupaka in New Zealand. The term white-throated shag is also reserved for the melanistic form there.<p>The little pied cormorant was originally described by French naturalist Louis Pierre Vieillot in 1817. In 1931, American ornithologist James Lee Peters was the first to consider this in a separate genus along with the pygmy cormorant (M. pygmaeus), little cormorant (M. niger), and the long-tailed cormorant (M. africanus). Since then, molecular work by Sibley and Ahlquist showed the little pied and long-tailed cormorants formed a group which had diverged early on from other cormorants. This group of "micro-cormorants" assumed the genus name Microcarbo, initially described by French naturalist Charles Lucien Bonaparte in 1855. The generic name is derived from the Ancient Greek mikros "small", and Latin carbo "black". However, most older authorities refer to this species as Phalacrocorax melanoleucus.<p>In the now-extinct Waray language spoken along the Adelaide River in North Arnhem Land, the species was known as mawa.<p>Three subspecies are commonly recognised:

Nome scientifico

Microcarbo melanoleucos

Autorità

(Vieillot, 1817)

Ordine

Suliformi

Famiglia

Phalacrocoracidae

Genere

Microcarbo

Areale e habitat

The species ranges across New Zealand, from Stewart Island to Northland, and across mainland Australia (although not in the arid interior of the west of the country) and Tasmania. It is also present in Papua New Guinea, Palau, Timor-Leste, the Solomon Islands, New Caledonia, and Vanuatu. In eastern Indonesia, the little pied cormorant's range includes Sulawesi, the Lesser Sunda Islands, Maluku Islands, and Western New Guinea, with non-breeding birds recorded in Java, Bali, and once off the coast of East Kalimantan. Widespread and common, it lives near bodies of water such as swamps, lakes, lagoons, estuaries and the coastline.

Migrazione

Resident species

Conservazione

Tendenza della popolazione

unknown