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.

Comments

Threats to Sea Turtles

Threats to Sea Turtles in Bangladesh Sea turtles, despite their ancient and majestic existence, face a multitude of threats in the coastal regions of Bangladesh. These threats have been observed during the course of our project, and they require urgent attention and action. Currently emerging threats are arising from the habitat alteration, lighting disturbance along the northern zone of Cox Bazar-Teknaf peninsular beach. There were some record of very severe egg poaching occurrence by brutally killing mother turtle. It suspected that the case was happening for long although limited scale. In last 17 seasons (2005-19) the organization released over 600 thousand olive ridley and green turtle hatchings in the wild through SRCWP project. This population hopefully maintaining the ecological balance in the BoB marine ecosystem. The offshore fishing community is being continuously motivated and trained and bycatch releasing is now common as fisher’s are cooperating and respecti...

Shark Finning

The Massacre of the World's Sharks for Soup BY EDWARD DORSON The world's sharks are quickly vanishing and it's primarily driven by the demand for shark fins as an ingredient of a status symbol soup devoured throughout Asia at weddings and banquets. Approximately 73 to 100 million sharks are killed annually worldwide just for their fins. Some shark populations are already functionally extinct, having declined by as much as 99%. The outcome of further inaction will soon create a vast jellyfish soup, formally known as the ocean. Sharks targeted by finners aren't taken whole; their valuable fins (up to $700 a kilo, at the time of this writing) are sliced off and the living mutilated shark is tossed back into the sea to sink and slowly die. It is despicably inhumane. The obliteration of 400 million years of evolution for some perceived social status with serving shark fin soup isn't just idiotic and cruel - it's tragic. A healthy ocean depends on sharks. Scientific...

Ocean Current

Ocean Current Skip to content ut Ocean Blue Project Donate Now Ocean Currents Map Why are Ocean Currents Important? Types of Ocean Currents So, what causes the ocean’s currents? Ocean currents are driven by tides, winds, or changes in the water’s density. There are two different types of ocean currents: surface currents and deep ocean currents. Together they create a complex system that affects our weather, marine travel, and oceanic ecosystems. 1 Surface Currents 2 Deep Ocean Currents 3 Tidal Currents Ocean Currents of The World The Great Pacific Garbage Patch This collection of litter (composed mostly of tiny pieces of plastic) is located in the North Pacific. The trash is collecting in the calm center of the North Pacific Subtropical Gyre. A gyre is a large system of swirling ocean currents. The North Pacific Subtropical Gyre is made of four separate currents: the California current, the North Equatorial current, the Kuroshio current, and the North Pacific current. These four c...

Marinelife Alliance

Search This Blog