Common Thresher Shark - Oceana Canada

Sharks & Rays

Common Thresher Shark

Alopias vulpinus


Sea fox, swingletail, whiptail shark, thintail shark, fox shark, swivel tail


Temperate and tropical waters in the Atlantic, Pacific and Mediterranean


Pelagic waters from 0-200 metres deep


Aggressive predator that feeds on schooling fishes


Order Lamniformes (mackerel sharks), Family Alopiidae (thresher sharks)


The common thresher shark is most notable for its long, top caudal fin, or tail fin. However, what you may not know about this shark is that they use this top fin to herd, whip, stun and catch their prey. Their top tail fin can grow to be three meters long – equivalent to up to half the length of their entire body. Their distinctive tail is useful for other purposes as well – the length helps them swim fast as they round up anchovies, herring and other schooling fish to then strike, stun and eat.


One of the best ways to identify the common thresher shark is their top caudal fin, or tail fin, which reaches lengths of up to 50 per cent of their body length. They have a short, rounded snout and large eyes that are positioned close to the front of their head. Adults average around four to six metres in length. Even though they have a short snout, they still have around 50 rows of triangular, sharp teeth that help them catch the small fish they eat. Common thresher sharks are strong swimmers and can leap out of the water thanks to the speed and power generated by their long tail fin.



Common thresher sharks are ovoviviparous, which means the eggs grow and hatch inside of the female before the female gives birth to “live” young. Their gestation period is around 9 months long with birth occurring in the spring. Females birth on average two to six pups, which are typically born at lengths of 114-150 centimetres. Sharks mature between three and eight years of age once they reach a specific size. Males mature at lengths of 3.3 metres and females at around 4.2 metres. The maximum life span of a common thresher shark is between 45 and 50 years of age.



Common thresher sharks are threatened by overfishing and population decline due to their slow maturation. In the United States and South Africa, they are considered a prize game fish for trophy and sport fishers and they are targeted by recreational fishing in Mexico. As well, they are often caught incidentally as bycatch in fisheries targeting other species, as well as in illegal, unregulated fisheries.



Common threshers sharks are not listed under the Species At Risk Act (SARA) in Canada, nor have they been assessed by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC). Even so, common thresher sharks have been classified globally as Vulnerable on the IUCN Red List. As a species that is late to mature and produces few offspring, common thresher sharks are highly vulnerable to pressures from overfishing. Habitat destruction of important, coastal nursery grounds also threatens the survival of their young.

Oceana Canada is working to protect Canada’s oceans for species like common thresher sharks. Find out more about our campaigns and join us in helping to bring abundance back to the ocean.