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.

Leopard Shark, resting on the Great Barrier Reef

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.

Releasing a shark that was accidentally caught

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

Tawny Nurse Shark, commonly named the “sleepy shark” in Australia for obvious reasons

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