Northern Bluefin/Longtail Tuna Thunnus tonggol
Distribution - Longtail tuna, also known as northern bluefin tuna, is a tropical species that frequently occurs in more southern waters of Australia's east and west coasts during summer. They are generally distributed throughout waters of northern Australia, from CocKBurn Sound in Western Australia to southern NSW (Twofold Bay, Eden).
Size - Longtail tuna reach a maximum length of 1.5 metres and up to 32kg in weight. The majority of fish caught by anglers weigh less than 15kg.
Characteristics - Longtail tuna are a member of the family Scombridae. These dark blue-backed fish are recognised by their short pectoral fins and slender bodies. Longtail tuna are also distinguished by the presence of elongated, colourless spots on the underside and belly, between the pectoral and anal fins.
Confusing species - Similar in appearance to southern bluefin, but possess a more streamline body, particularly the rear half.