Posted on April 4, 2012
Mention “sharks” to a group of people and you will get a range of opinions from blood-thirsty killers as depicted in “Jaws” to graceful predators important for ecosystem health (the latter remark is probably from a marine scientist, but you get my drift). I’ve been lucky enough through work and travel to have dived with a few sharks, and although some experiences were heart-thumping I’ve never been threatened by one. These days it’s more likely the reverse.
Every year, less than 5 people are killed by sharks, while we kill upwards of 73 million sharks. Often the shark is killed solely for its fins, to be used as soup-thickener; the rest of the shark is dumped overboard. This is just not wasteful fishing, it is unsustainable. Many commercially fished shark species grow slowly, live for a long time, and produce very few young. These “life-history” characteristics mean that it is relatively easy to fish-down shark populations.
Globally, shark populations along with other large, predatory fish are at about 10% of pre-fishing levels. In some areas, it is even worse. For some Caribbean countries, sharks (apart from the odd nurse shark) are basically gone. Loss of a top predator from the food chain can have wide ranging impacts to the surrounding habitat. However, it is not all doom and gloom. A few countries have recently recognized the ecological importance of sharks (plus realized shark diving brings in dollars) and have “shark sanctuaries” where shark-fishing is prohibited. The list of countries is small, but growing, and includes The Maldives, The Bahamas, Palau, Tokelau and Honduras. So, if you are lucky enough to see a shark in the wild, enjoy the moment and don’t consider yourself as food.
Dr Alan Duckworth, Research Scientist