Tasman Sea island thrush

The Tasman Sea island thrush (Turdus poliocephalus) was a forest-dwelling bird from the thrush family. It once lived on Lord Howe Island and Norfolk Island in the Pacific Ocean, but is now extinct. This bird belonged to a larger group called the "island thrush" complex, which was reclassified into 17 distinct species following a 2023 molecular phylogenetic study. Both of its subspecies died out during recorded history.

In 1801, English ornithologist John Latham formally described the species based on a specimen collected on Norfolk Island. He gave it the scientific name Turdus poliocephalus; the name combines the Ancient Greek words for "grey" or "grizzled" (polios) and "headed" (-kephalos). Previously, the "island thrush" included about 50 subspecies and ranged from the Philippines through the Greater Sundas, Wallacea, and New Guinea to Polynesia. The 2023 study split this complex into 17 species using both morphological differences and molecular data.

Two subspecies are recognized, both now extinct: † Turdus poliocephalus vinitinctus (Gould, 1855) – Lord Howe Island † Turdus poliocephalus poliocephalus Latham, 1801 – Norfolk Island

The nominate race, T. p. poliocephalus, was still fairly common as recently as 1941. By 1975, however, it had vanished due to introduced black rats, habitat loss, and hybridization with the closely related common blackbird after human settlement. The Lord Howe Island subspecies, T. p. vinitinctus, also died out in historical times.