Obtaining shark fins need not involve finning at all, however. He notes great strides in legislation that have reduced the number of sharks finned at sea in at least 17 countries.
Indeed, by definition, exploiting a resource sustainably requires whole animal use, Simpfendorfer explains. In the case of MSC-certified Atlantic dogfish, the heads become lobster and crab bait; back meat becomes British fish and chips; belly flaps are a German delicacy; liver supplies nutraceuticals; fins and tails headline east Asian soup; and leftovers become agricultural fertilizer, says Massachusetts-based attorney John Whiteside, Jr.
But for sustainable shark fishing to work, its products have to be labeled and traceable back to a well-managed source—a requirement that very few of the sustainably harvested fins currently on the market now meet. Traceability challenges are not technological. Determining how to harvest some sharks sustainably while protecting others that cannot be harvested at all will require further work.
Dulvy and Simpfendorfer suggest developed countries must support developing ones in improving traceability and negotiating international treaties for fisheries and trade. Bycatch remains a problem, too. Tuna fisheries, for example, often hook pricey species like blue sharks and shortfin makos and then sell them, rather than releasing them. Meanwhile bycatch sharks that are not economically valuable and thus released back to the sea may not fare well either.
New satellite tagging research by Steven Campana, a shark biologist at the University of Iceland who was not affiliated with the research, says a quarter of those live-released sharks may die from the stresses of capture and handling. Another concern: legal shark fishing could hide illegal trade. In his view it is better to have at least some sustainable, scientifically well-managed products in the marketplace. Lesley Evans Ogden is a freelance science journalist based in Vancouver, Canada.
She can be found on the Web at www. Follow her on Twitter ljevanso. Follow Lesley Evans Ogden on Twitter. Already a subscriber? Sign in. Thanks for reading Scientific American. Create your free account or Sign in to continue. Shark cartilage pills do not specify which species of shark are used in their production. These pills are often made with a cocktail of shark chondroitin from multiple species — whatever is available at the time.
These whale sharks ended up in Shark Liver Oil capsules being sold in the U. It is illegal to kill whale sharks in China, and its illegal to profit from a crime committed in another country, otherwise known as a Trans National Wildlife Crime.
Technically, by purchasing these pills, legally YOU the buyer are also an accomplice in a Trans National Wildlife Crime, in the same way that if you purchase ivory, and therefore have the illegal blood on your hands. So you may want to watch out what you and your family are purchasing. This is what all the producers of shark cartilage will tell you, even those in Kesenuma, Japan. The problem is that whoever you talk to — shark fin traders, cartilage pill producers, or meat vendors — each one claims to be using the by-catch of the other!
Meanwhile more than million sharks are being wiped out annually , and this is the reality. Fishermen fish for money, and so long as people will pay for shark parts they will continue to kill them. If the cartilage were literally a waste item that would be generally thrown away, you would think it would be free!
But no, the fishermen make money from the cartilage, therefore proving a financial demand is present, which continues to fuel the targeting of sharks. The myths being spread about the benefits and powers of shark cartilage range from the slightly believable to the absolutely far-fetched. Manufacturers will make up any sales pitch to say why their product is better, more effective, or purer than that of their competitors. Other companies around the world have gone a whole lot further in their statement, claiming that shark cartilage is a cure for cancer.
For instance, most sharks caught off the shores of West Africa are younger than two years. Conservationists say that the fin trade is threatening the survival of some species, and that the sharks should be allowed to grow up and reproduce before being caught. Because Chinese chefs will pay more for the long strands of cartilage in larger fins, Fong says that fishermen could maximise profits by allowing sharks to reach adulthood before they are caught.
In economic terms, if the sharks are left for longer than that they become an increasingly wasted asset. But if caught any younger, they will not fetch such a good price. It grows to about 2 metres in length and is, according to the World Conservation Union, highly vulnerable to overfishing.
The economically optimum solution for the blacktip is to allow them to mature to around 10 years old. This is only early middle age for the blacktip, which could expect to live to around 20 years, but it is getting on for twice the age at which it starts to reproduce.
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