The threat looms for species that live in the depths. One in seven sharks is in danger of becoming extinct due to overfishing. It happens with deep-sea sharks and rays.
They are caught incidentally in fisheries that target species of higher commercial value. However, they are preserved for the value of their oil and meat. This comes on top of a recent global expansion of the shark liver oil trade.
deep fishing
«Half of the world’s sharks are found below 200 meters. Below where the sunlight reaches the ocean,” Nicholas Dulvy says in a statement. He is a Professor of Biodiversity and Marine Conservation at SFU (Simon Fraser University). “The first time they see sunlight is when they are taken onto the deck of a fishing boat.”
This new analysis from Dulvy evaluated more than 500 species of sharks and rays. It had the participation of more than 300 experts from around the world. He found that around 60 species are threatened with a high risk of extinction due to overfishing.
«Fishermen are encouraged to fish on the high seas. They fish up to a kilometer deep,” says Dulvy. Deep-sea sharks and rays are among the most sensitive marine vertebrates. It is due to their long life expectancy and low reproduction rates. Some species may take 30 years or more to mature.
Sharks and rays maintain their buoyancy by having a fatty liver, but this fat is highly prized. It is widely used in cosmetics, nutritional supplements and medicines, such as vaccines. Demand for fermented skates, a traditional Korean delicacy, also increased.
coveted liver
One in seven sharks is in danger due to interest in their liver oil. This international trade must be regulated. Protecting 30% of ocean depths (200 to 2,000 meters) would provide 80% of species with partial protection throughout their range.
It’s not too late to protect sharks. But if the necessary measures are not taken, we will soon be mourning the loss of more species.
