WHAT TO LOOK FOR: A stout shark with a very long curving caudal fin, about as long as its entire body.

COLOUR: Dark grey, bluish or greenish above, white below.

SIZE: Adult males range from 10.5 ft (3.2 m) to at least 13.8 ft (4.2 m), adult females 12.3 to 18 ft (3.76 to 5.5 m). Maximum total length is 18 ft, possibly 20 ft (6. I m).

TEETH: Small, broad-based blade-like teeth. Its tooth formula is: 19/26-2-19/26.
21/27-2-21/27

HABITAT: Coastal over the continental and insular shelves, and epipelagic from land in temperate to tropical seas. Found from the surface to depths of 1200 ft [366 mi.

DISTRIBUTION: Circumglobal in warm seas.

BIOLOGY:
Prey - Mostly small schooling fishes including mackerels, bluefishes, clupeids, needlefishes, lancetfishes and lanternfishes. Also feeds on squid, octopus and pelagic crustaceans, and occasionally seabirds.
Reproduction - Ovoviviparous. Embryos are ovophagous and consume smaller siblings. Litter size ranges between 2 and 4 (usually 2). Size at birth 3.7 to 4.9 ft (1.14 to 1.50 m).

BEHAVIOUR:
Feeding : A thresher shark herds and stuns prey with its long, whiplike tail, and sometimes it vaults completely out of the water Thrasher sharks are often caught on longlines by being tail-hooked.

DISPOSITION:
Small specimens have been seen underwater by divers (at the surface or close to the bottom) and have circled them at the limit of visibility without displaying aggression. Danger to humans - Probably not normally dangerous. There are two unconfirmed attacks on boats by this species. Two other species in the family, A superciliosus and A. pelagicus, have never been implicated in attacks on humans.