- Sharks have roamed our seas for more than 400 million years, which means they inhabited the earth for nearly 200 million years before dinosaurs.
- Sharks are fish with skeletons made of cartilage instead of bone, but sharks’ slow growth and late maturity mean they have more in common with sea turtles and marine mammals than bony fish such as flounder or tuna.
- Sharks are a remarkably diverse group of fish. They range from less than a metre to 20 metres in length; they are found in most coastal regions but also in the deep ocean and even in fresh water. Some sharks lay eggs, but most give birth to live young. Most are top predators while a few feed on plankton. Sharks in turn are preyed upon by other sharks and sometimes killer whales.
- The term ‘shark’ often refers not only to shark species but also to the closely related rays and skates, as well as the oft-overlooked chimaeras (rat, rabbit and elephant fish).Collectively these cartilaginous species are known as chondrichthyan fish (forming Class Chondrichthyes).
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The shark existence of the east coast of the USA decreased in the last 15 years substantially. The number of the hammerhead sharks sank around 89%, those of the thresher sharks around 80%, those of the great white sharks around 79%. The populations of the mako sharks, blue sharks and tiger sharks sank around 40-65%. The existence of the sandbar sharks were reduced in the last 10 years by overfishing by 85-90%.
Canadian researchers announce a decrease of the oceanic whitetip shark by around 99%. They are almost extinguished in certain regions already.
Sharks are not only caught actively for their meat, fins or cartilages. Millions of sharks die as non-usable catch (bycatch) in the nets and longlines of the swimming fish factories.
In the year 1991 the longline fishery brought in 8.3 million sharks world-wide. It is assumed that about half of it were blue sharks. More than 87% of these 8.3 million sharks were thrown away!
In the USA, along the Atlantic Coast and the Gulf of Mexico, annually approx. 2.5 million sharks are fished by sportfishing (game fishing). From that approx. 20-40% (500’000 – 1’000’000 sharks) got killed.
The population of all sorts of sharks is worldwide extremely threatened. In total 82 shark and ray species are registered on the so called “Red List” of the World Conservation Union.
Filed under Save Sharks · Tagged with age, approx, Atlantic, Atlantic Coast, blue, blue sharks, bycatch, canadian researchers, car, cartilage, catch, Co, coast, conservation, decrease, ear, existence, fact, fin, fins, fish, fish factories, fishery, fishing, game, game fishing, Got, Great, great white shark, great white sharks, Gulf of Mexico, half, hammerhead, hammerhead sharks, head, line, List, longline, longline fishery, longlines, mako, mako sharks, meat, number, ocean, oceanic whitetip shark, overfishing, population, ray, Red, region, research, researcher, round, row, sand, sandbar, sandbar sharks, sea, serv, shark, Shark Existence, shark existence of the east coast, Sharks, Sharks are fish, Species, sport, swimming, threat, Threatened, thresher, thresher sharks, tiger, tiger shark, Tiger Sharks, Union, US, USA, way, White, white shark, white sharks, whitetip, Wide, world, world conservation union, worldwide, year, year 1991
