tuna

Any of various large marine bony fishes of the mackerel family, especially the genus Thunnus, popular as food and game. Albacore T. alalunga, bluefin tuna T. thynnus, and yellowfin tuna T. albacares are commercially important.

Tuna fish gather in shoals and migrate inshore to breed, where they are caught in large numbers. The increasing use by Pacific tuna fishers of enormous driftnets, which kill dolphins, turtles, and other marine creatures as well as catching the fish, has caused protests by environmentalists; tins labelled ‘dolphin-friendly’ contain tuna not caught by driftnets. Thailand is a major tuna-importing and canning country.

Overfishing is causing a reduction in tuna stocks around the world. In spite of the introduction of quotas in Australia in the 1980s, the country's catch of southern bluefin tuna in 1990–91 was 5,000 tonnes – the lowest since 1962, and the species could be in danger of extinction. Tuna stocks in the Atlantic declined by almost 90% during 1970–92.