Shark populations across the world are suffering from extreme overfishing. Sharks are hunted for their fins, a key ingredient in shark fin soup, and fishermen often slice the dorsal fin off of the shark and throw the wounded animal back into the ocean, where it bleeds to death. While some sharks are hunted for their meat in Europe and Asia, species that have a high fin value and a low meat value are especially at risk, such as the hammerhead, because these sharks aren’t used for their meat. Sharks are also unintentionally captured in tuna fishing nets and gillnets, and then discarded as unwanted by-catch. The shark fishing industry is globally unregulated, and an estimated 73 million sharks are killed per year in the United States alone, with that number rising to over 100 million in global annual totals.
Shark fin soup is a delicacy in China, is commonly served at weddings and other formal events and is considered a symbol of health and of one’s elevated status. Quality shark fins continue to be in high consumer demand across China, making shark finning increasingly profitable. Blue shark fins are among the most common type found in soups, since blue sharks are high in population, and over 10 million blue sharks are killed per year for their fins.
One-third of a total of 64 shark species are endangered and threatened by overfishing, which is a widespread, global problem that occurs in all of our oceans. Since sharks have no oceanic predators, they are critical in controlling the population of other fishes. A decrease in the shark population, at the top of the food chain, indirectly results in damage to coral reefs and loss of marine plant life, at the bottom of the food chain, since less sharks leads to more predatory fish, which eat large amounts of sea kelp and other plants. In North Carolina, shark fishing has also led to an increase of rays and skates – the sharks’ prey – which has, in turn, contributed to a decrease of shellfish and scallops –the rays’ prey.
Since sharks reproduce and mature slowly, their populations can take over a decade to recover from overfishing. Government leaders in the United States and abroad should recognize and control this tragic problem by setting limits on shark fishing and banning the cruel practice of shark finning, as there are currently no national or international limits on shark fishing, even for species nearing extinction. The dusky shark population in the western Atlantic has declined by an estimated 80 to 99 percent in the past 20 years, while the hammerhead shark population in the same U.S. region has declined by 85 to 99 percent.
Due to the unmonitored nature of the shark fishing industry, researchers have difficulty determining which particular shark populations suffer the most from overfishing. However, a new method of tracking sharks by DNA has shed light on the magnitude of this problem. Scientists at Stony Brook University in New York sampled DNA from dusky and hammerhead sharks, and found that sharks from different regions of the world carried different mitochondrial DNA. Using this DNA to determine how many sharks from each region are being hunted, they found that one-fourth of hammerhead shark fins sold in Asia came from U.S. Atlantic sharks, a region in which the shark population has suffered from a steep drop.
To voice your concern for endangered shark populations to the United States National Oceanic and Atmospheric Administration (NOAA), add your name to this Change.org petition. If you live near the coast, you can also alert your local fisheries management service and inform them that you support shark conservation efforts.
Photo credit: flickr.com/photos/tanj/159886890/