Why sharks might not win
Some shark species are on the verge of extinction, leaving the shark population in a precarious position.
The young surfer paddles out deeper into the ocean, bobbing up and down as the undulating swell of each wave rolls toward the distant shore.
Sitting up on her board, she dangles her legs into the dark mass of water and looks behind her.
Something is out there–gleaming in the dying rays of the day. A cold dread steals over her as she makes out the unmistakable shape of a grey fin–a shark’s fin. She can think of nothing, nothing but the monster rising up out of the deep toward her, jaws open and teeth bared, those stark, jagged teeth ripping into her soft flesh, tearing her whole leg away in a single mouthful.
People Bite Back
Is it any wonder people are afraid of sharks? Movies, books, and the popular media have demonized sharks to the point where people are seized with an irrational fear every time they stick their toes in the water. The truth is, only about eight to 12 people in the world are killed by sharks annually. In North America, you’re 30 times more likely to be killed by a lightning strike. For sharks, the odds aren’t as good–every year humans kill more than 100 million sharks.
In fact, we’ve become such overzealous shark killers that some shark species are on the verge of extinction. There are now 110 species of shark listed in a threat category on the World Conservation Union’s Red List. A further 95 species are listed as Near Threatened.
Commercial fishing practices are to blame for about 50 percent of all sharks killed. These sharks are caught accidentally by tuna and swordfish longline fisheries (bycatch). Longlines are up to 90 kilometres long and bristle with thousands of hooks just below the surface that catch sharks lured by the bait.
Sharks are also killed out of fear, or for sport, but mostly out of greed. Lucrative shark products include shark-leather goods, teeth and jaw ornaments, liver oil, medicines (including vitamin A), and skincare products. However, the most valuable part of the shark is that quintessential icon of fear–the shark fin.
Shark fins are primarily used in the making of shark fin soup, an Asian delicacy. Shark fins actually have no nutritional value and no flavour. The appeal lies in the price–at over $200 a bowl, this delicacy has long been a status symbol in traditional Chinese culture. However, the growth of the Chinese economy has seen demand for shark fins rise by up to 400 percent in the last 15 years, fetching up to US$564 per kilo. Shark fin soup is now mass produced and is commonplace at business dinners, banquets, and weddings.
When sharks are caught as bycatch, they can legally be stripped of their fins. However, with demand as high as it is, many fishers hunt sharks just for their fins, a brutal and illegal practice known as shark finning. The fin of the shark is hacked off with a sharp knife before the shark is tossed back into the water–often still alive. Unable to swim, the shark suffers a slow and agonizing death from loss of blood, drowning, or starvation.
Shark finning harvests only 2 to 5 percent of the shark and wastes the remaining 95 percent. Shark carcasses are discarded to save space and to increase the number of sharks harvested in one fishing trip. This wasteful practice has been banned by many countries, but it is largely unmanaged and unmonitored.
So, why should we care if the shark becomes extinct? After all, sharks are not as cuddly as panda bears, nor as smiley as dolphins. Besides, sharks are pretty tough creatures–wouldn’t they just bounce right back?
Sadly, the answer is no. Sharks are far more vulnerable to overfishing than many people realize. In fact, sharks are more similar to mammals than to fish. Most fish reach maturity in just a few years and lay millions of eggs per year, whereas sharks take many years to reach maturity. Most sharks don’t start reproducing until they are 12 to 20 years old and then may only have one or two offspring a year. Some scientists believe that sharks should not be fished at all since their low reproductive rate can’t compensate for great losses in numbers.
Sharks serve a useful purpose in the ecosystem–they stabilize population fluctuations and remove diseased and genetically defective individuals. Christine Snovell of the National Coalition for Marine Conservation explains, “Sharks are an apex predator, like lions or wolves on land. If you remove that important link from the top of the food chain, you’re going to have some real problems all the way down the line.”
Conservationists around the world are fighting to protect the shark, with organizations such as the Sea Shepherd Conservation Society (seashepherd.org) and WildAid (wildaid.org) leading the way. Their aim is to raise awareness of the threat to sharks, promote sustainable management of shark populations, and end the practice of finning. As Peter Knights, executive director of WildAid, says “These animals have been here for 400 million years and they may disappear in one generation, not to provide people with basic food but for a solely luxury item.” Now that’s a real horror story.
Taking the top predator out of the food chain will alter the ecology of the ocean. The results of such a radical change are unpredictable, but there are precedents.
A shark population in Tasmania collapsed after two years of overfishing. Shortly after, all the lobsters disappeared. Octopus numbers, the lobsters’ major predator, had significantly increased because there were no sharks left to keep the octopus population down.
A decreasing number of sharks off the US Atlantic coast correlated with an increase in cownose rays whose main prey, scallops, subsequently diminished in numbers, irrevocably damaging the ocean ecology and impacting the local scallop fisheries.