The headlines about recent shark attacks on humans along the North Carolina coast have many people feeling frightened, even though such attacks are statistically rare. But the truth is that the world’s 450 species of sharks, most of which pose no danger to humans, have a lot more to fear from humans.
Consider this: Each year, for every person killed by a shark, about 10 million sharks are killed by humans.
Across the planet’s oceans, vast numbers of sharks are being wiped out, at a rate faster than they can reproduce. It’s a harvest that eventually could disrupt aquatic ecosystems, and even hurt the food supply upon which much of the world’s human population depends.
And the real tragedy is that humans are killing most of these sharks not because they’re dangerous or for food, but out of carelessness. Commercial fishing operations, which are out to catch tuna, swordfishes and other high-value food fishes, use methods that inadvertently hook many sharks as well. In fishing circles, this is known as “bycatch.”
It’s still in our abilities to save sharks, but the window of opportunity is closing rapidly. Because sharks are highly migratory, it’s not enough for the U.S. to take steps by itself to protect shark populations. It’s essential to have a joint international effort among the world’s fishing nations.
In the open ocean, for example, ships use fishing lines that are up to 30 miles in length, with thousands of hooks attached. They often use J-shaped hooks, which can get caught in a shark’s throat or stomach and cause fatal injuries, so that they can’t be released back into the ocean. Closer to shore, fishing operations use gill nets, which are made of a nearly invisible monofilament that efficiently traps large numbers of fishes—including sharks.
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