Australian pied cormorant

Australian pied cormorant
Scientific classification
Kingdom Information
Domain	Eukaryota
Kingdom	Animalia
Subkingdom	Bilateria
Branch	Deuterostomia
Phylum Information
Phylum	Chordata
Sub-phylum	Vertebrata
Infraphylum	Gnathostomata
Class Information
Superclass	Tetrapoda
Class	Aves
Sub-class	Neornithes
Order Information
Order	Suliformes
Family Information
Family	Phalacrocoracidae
Genus Information
Genus	Phalacrocorax
Species Information
Species	P. varius
Synonyms	Hypoleucos varius
Population statistics
Population	Unknown (2016 est.)
Conservation status	Least concern

The Australian pied, or yellow-faced cormorant (Phalacrocorax varius) is a species of aquatic bird of the family Phalacrocoracidae, and found over much of Australia, New Zealand, and adjacent islands.

Description

Australian pied cormorants are large, with a body length of 25.6 inches, a wingspan of 51.3 inches, and weigh 45.8 to 77.6 ounces. Males are larger and heavier than females. Adult birds are black above, from the forehead to the top of the head, the neck and the back to the tail feathers. The sides of the head are white, as is the throat, neck, chest and belly. The beak is light gray to ivory in color and gets a little darker towards the head; the female's beak is narrower and shorter than that of the males, with both having bare red skin at the base and underside. The skin surrounding the eye is surrounded by a bare, blue bead of skin, while immediately in front is a patch of bare, bright yellow skin, giving the bird one of its names. Young birds are similar to adults, but with dark brown upper plumage instead of black.

Subspecies

As with all cormorants, the exact systematic position of the Australian pied cormorant is controversial, with some authorities placing the species in the genus Hypoleucos, but this view is not generally accepted. There are currently two subspecies:

• Phalacrocorax varius hypoleucos; Australian coast and interior; Tasmania (vagrant)
• Phalacrocorax varius varius; New Zealand, Stewart Island

Range and habitat

The Australian pied cormorant is common on the waters of Australia and New Zealand, where it is known by its Māori name of kāruhiruhi. The species lives in predominantly marine coastal areas, but also populates estuaries, the lower reaches of rivers, wetlands and larger inland lakes.

Diet

Fish make up to 90% of its diet; in addition, the Australian pied cormorant eats crayfish or other invertebrates such as squid. Like all cormorants, the species prefers to hunt its prey by diving and swimming underwater. The species prefers shallow waters and often hunts near mangroves and other fish-rich structures on the coastline.

Reproduction

The start of the breeding season varies greatly and depends on the local conditions, with southern populations breeding in the spring, and northern populations breeding year round. In the northern range, the start of nesting depends on the available food supply and the start of the rainy season. The species breeds in colonies from a few hundred to several thousand breeding pairs, often in mixed colonies with other coastal birds. The nest is preferably laid out in trees and bushes, rarely on the ground' more often than not older or abandoned nests are reused rather than new ones made. It consists of sticks, algae and grass and is padded with feathers. Usually three eggs are laid, but the size of the nest varies between one and five eggs. The incubation is about 30 days. After a few days the chicks, naked after hatching, grow down, which is brown on the back and white on the belly. About 60 days after hatching, the young birds are fledged, but are fed by their parents for another 80 days. On average, 25 percent of the young birds in a nest live to fledging.

Threats

The IUCN has classified the species as "least concern", due to its high population, wide range, and the fact that it eats fish which are not economically viable for humans. Habitat destruction is is a concern, yet is limited and localized, since Australia and New Zealand do not have a high population density.