The Norfolk Island Thrush (Turdus poliocephalus poliocephalus), also known as the Grey-headed Blackbird or Guava Bird, was a bird in the Thrush

True thrush

The true thrushes are medium-sized mostly insectivorous or omnivorous birds in the genus Turdus of the thrush family Turdidae.The genus has a cosmopolitan distribution, with species in the Americas, Europe, Asia, Africa and Australia. Several species have also colonised some oceanic islands, and...

 family endemic to Norfolk Island

Norfolk Island

Norfolk Island is a small island in the Pacific Ocean located between Australia, New Zealand and New Caledonia. The island is part of the Commonwealth of Australia, but it enjoys a large degree of self-governance...

, an Australia

Australia

Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

n territory in the Tasman Sea

Tasman Sea

The Tasman Sea is the large body of water between Australia and New Zealand, approximately across. It extends 2,800 km from north to south. It is a south-western segment of the South Pacific Ocean. The sea was named after the Dutch explorer Abel Janszoon Tasman, the first recorded European...

. It is the extinct

Extinction

In biology and ecology, extinction is the end of an organism or of a group of organisms , normally a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and recover may have been lost before this point...

 nominate subspecies

Subspecies

Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...

 of the Island Thrush

Island Thrush

The Island Thrush is a common forest bird in the thrush family. Almost 50 subspecies have been described, ranging from Taiwan, through South East Asia and Melanesia, to Samoa, exhibiting great differences in plumage...

 (Turdus poliocephalus).

Description

The Norfolk Island Thrush was mainly dark brown in colour, with a pale grey-brown head and upper breast. It was about 21 cm in length, with a wingspan of 34 cm and a weight of 55 g. It had a yellow bill, orbital ring and legs. Males and females were similar in size and appearance.

Habitat

The Norfolk Island Thrush used to be common in forest and was often seen in gardens adjacent to rainforest remnants.

Breeding

The subspecies nested in trees, including the introduced lemon

Lemon

The lemon is both a small evergreen tree native to Asia, and the tree's ellipsoidal yellow fruit. The fruit is used for culinary and non-culinary purposes throughout the world – primarily for its juice, though the pulp and rind are also used, mainly in cooking and baking...

 tree. The clutch size was 2-4.

Feeding

The Norfolk Island Thrush foraged mainly on the ground, in leaf litter, for small invertebrates, seeds and fallen fruit.

Status and conservation

The subspecies became extinct around the late 1970s, with the last confirmed record in 1975. The cause of its extinction is attributed to a combination of clearing of native vegetation and predation by rat

Rat

Rats are various medium-sized, long-tailed rodents of the superfamily Muroidea. "True rats" are members of the genus Rattus, the most important of which to humans are the black rat, Rattus rattus, and the brown rat, Rattus norvegicus...

s and feral cat

Feral cat

A feral cat is a descendant of a domesticated cat that has returned to the wild. It is distinguished from a stray cat, which is a pet cat that has been lost or abandoned, while feral cats are born in the wild; the offspring of a stray cat can be considered feral if born in the wild.In many parts of...

s. Additional factors were competition with introduced Song Thrush

Song Thrush

The Song Thrush is a thrush that breeds across much of Eurasia. It is also known in English dialects as throstle or mavis. It has brown upperparts and black-spotted cream or buff underparts and has three recognised subspecies...

es and Common Blackbirds, as well as by interbreeding with the latter species producing sterile offspring.