Sharks and Skates
There are many different species of sharks and skates, cartilaginous fish belonging to the subclass Elasmobranchii of the class Chondrichthyes.
Shark, rock cod, skate, raja fish, imitation scallops
Many species are fished and sold under the generic name of “shark.” In some countries, dogfish shark is used as a substitute for cod in fish and chips and sold as “rock.”
Depending on the species, sharks have a life span of 20 to 200 years. Sharks have more in common with sea turtles and marine mammals than bony fish like tuna. It is imperative that they are protected in the same way. Sharks are extremely vulnerable to overfishing because they mature late (some species do not reproduce until they are 35 years old) and produce few young at a time. They cannot reproduce fast enough to compensate for the rate at which they are being killed. Sharks are not a threat to humans, but humans are a serious threat to sharks!
Skates also grow slowly and are long-lived, and many skate populations are severely depleted as a result of overfishing and poor management.
It is estimated that 100 million sharks are killed each year. In the long term, this alarming figure puts the survival of certain species at risk. Recent studies have shown that some shark populations have already been drastically reduced. It is estimated that half the sharks killed each year are caught accidentally in nets intended for other fish.
Though the stock situation varies greatly depending on species and region, the stock levels for the majority of the sharks is very worrying. Despite the mounting evidence regarding shark overfishing and stock depletion, very few countries have placed any restrictions on shark fishing.
The status of an increasing number of species of skates is of great concern and some are listed as vulnerable, endangered or critically endangered by the International Union for the Conservation of Nature (IUCN).
Many species of skates are caught by bottom trawling, which harms seabed habitats and unintentionally catches high numbers of immature fish and other unwanted species. This bycatch is thrown back into the sea, dead or dying.
Many sharks are killed only for their fins, which are used to make traditional specialties such as shark-fin soup, particularly esteemed in Asia, where a bowl of shark-fin soup can cost up to $100. Shark fins are especially prized for their supposed medicinal properties. It is true that anti-angiogenic substances that combat cancer have been extracted from shark cartilage. However, there is no proof that shark-fin soup has any of the medicinal or aphrodisiac properties attributed to it.
Each year, over 3,000 tons of shark fins pass through the Hong Kong market alone. To obtain the fins, they are cut off when the shark is still alive, and the animals are thrown back into the sea to die a slow and painful death. Despite the banning of this technique in many countries such as the United States and Australia, it is still very common.
A few shark species feed on plankton, while the vast majority are predators, and therefore at the top of the food chain. As such, they play a fundamental regulatory role, eating weaker fish, carcasses and sick animals and thereby limiting epidemics in the natural environment.
Because of their high position in the food chain, shark meat can contain significant concentrations of mercury residues and other pollutants such as dioxins and polychlorinated biphenyls (PCBs).
Shark and skates should not be eaten.
Consult online guides for sustainable alternatives in your region.