The Black-naped Tern (Sterna sumatrana) has an extremely large range, which mostly extends across the tropical and subtropical areas of the Pacific and Indian Oceans, along the coast.
Taxonomy / Sub-species and Distribution:
The Black-naped Tern is believed to be closely related to the Roseate Tern (Sterna dougallii) – although the chick patterns are very different. This species is sometimes considered monotypic, but for the most part, it is divided into races based on shape. Two subspecies are recognized.
Subspecies and Distribution:
- Sterna sumatrana sumatrana – nominate species (Raffles, 1822) – In the eastern Indian Ocean and Pacific – the Andaman Islands, India, east to southern Japan and China, south through Indonesia, Malaysia, the Philippines, and New Guinea to north-east Australia and some islands in the western-central Pacific.
- Sterna sumatrana Mathews (Stresemann, 1914) – In the western Indian Ocean it breeds on the Aldabra and Amirante Islands, Seychelles, Chagos Islands (British Indian Ocean Territory), and the Maldives and can be found on the eastern African coast.
The tern is about 30cm long with a wing length of 21-23cm. Their beaks and legs are black, but the tips of their bills are yellow. They have long forked tails.
The Black-naped tern has a white face and breast with a grayish-white back and wings. The first couple of their primary (wing) feathers are grey.