Shark & Rays

Sharks & Rays

Pelagic Thresher Shark

Alopias pelagicus

Sharks have played a vital role in maintaining healthy oceans for hundreds of millions of years as a top predator. More than 450 species of sharks cruise the world’s oceans, ranging in size from 8 inches to a whopping 40 feet long. But today, nearly one in four sharks and their relatives are threatened with extinction. A major cause is the demand for shark fins. Every year, fins from as many as 73 million sharks end up in the global fin trade.

Learn fun facts and how you can help your favorite sharks - from great white sharks to hammerhead sharks.

DISTRIBUTION

Tropical to temperate latitudes of the Pacific and Indian oceans

ECOSYSTEM/HABITAT

Coastal to open ocean (pelagic)

FEEDING HABITS

Active predator

TAXONOMY

Class Chondrichthyes, Order Lamniformes (mackerel sharks and relatives), Family Alopiidae (thresher sharks)

With their long, whip-like tails, thresher sharks are one of the most easily recognized species of sharks. Pelagic thresher sharks are the smallest of the three species of thresher sharks, averaging about 10 feet (3 m)long. They are highly migratory, inhabiting the pelagic waters of the Pacific and Indian oceans, including off the coast of South Africa, western Australia, Taiwan, and California.

Like most sharks, pelagic thresher sharks are mainly solitary. They feed primarily on fish, such as herrings and mackerels, but will also eat pelagic squid. Pelagic threshers are thought to use the elongated lobe of their caudal fin to slap the water and stun schooling fish, like sardines, while they hunt. Like other species of thresher sharks, these threshers also sometimes use their extremely long tail to corral a school of prey into a tight ball, making it easier to catch and eat.

Although they are the smallest species of thresher shark, pelagic threshers reach sexual maturity later than the rest of their family, around 7 – 13 years old. Females give birth to live pups, typically with an annual litter of around 2. These pups are between 5.2 and 6.2 feet (1.6 and 1.9 m) long at birth. This relatively low reproductive rate is one of the reasons that pelagic threshers are currently classified as “Endangered” by the IUCN Red list. Though adult thresher sharks have no natural predators, they do face serious human-made threats, primary fishing pressure from both targeted fishing and bycatch. The demand for their meat and fins puts pelagic thresher sharks at serious risk of extinction, and their population has decreased by 50-79% over the last three generations.

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