Thresher Shark

Average size between 300 cm and 500 cm (up to 230 kg). Maximum total length about 610 cm and 450 kg. Typical thresher shark with a very long tail. The upper lobe is about half the entire size of the shark. Small eyes with orbits that do not expand onto dorsal surface of head. Forehead is strongly convex in lateral view. Frist dorsal fin erect and angular. Pectoral fins are falcate and narrow-tipped. Display dark, metallic shine, coloration with ventral surface white extending over pectoral fins bases as a very conspicuous patch.




Lives in coastal waters over the continental and insular shelves, and epipelagic. Found from the surface down to 360 m, with juveniles living in shallow waters. Thresher sharks are solitary creatures which keep to themselves. It is known that thresher populations of the Indian Ocean are separated by depth and space according to gender. All species are noted for their highly migratory habits. A very active and fast swimmer, can leap out of the water. This species and the other thresher sharks possess an elevated body temperature due to a special blood circulatory system (rete mirabile) that enables them to live in colder waters. Thresher shark feed primarily on small schooling fishes (such as herrings, sardines) that are herded together with their tails and then stunned or killed with it.



No distinct breeding season is observed by thresher sharks. Aplacental viviparous (ovoviviparous), with uterine cannibalism. Two pups per litter. The pups are born in open water and show a fast growth. Size at birth between 115 cm and 150 cm. Thresher sharks are slow to mature; males reach sexual maturity between seven and 13 years of age and females between eight and 14 years in bigeye threshers.

Appearance

Biology

Reproduction