San Diego Shark Population Takes A Dive

February 27, 2006

Release from: KFMB.com (San Diego, CA)

Welcome to my paradise – diving with sharks. While some people hope they never have to see a shark, others are worried that they’re not seeing enough.

The best chance to see a shark may be through a glass window, but scientists caution that it’s a bad sign that we are seeing fewer predators in our backyard.

Birch Aquarium at Scripps allowed me to get cozy with its leopard sharks in a 70,000-gallon tank. In the past, I’d head down to the waterfront and hop on a boat with a shark cage, but the only local shark diving company stopped taking local trips.

Paul Anes, better known as “Doc Anes” of San Diego Shark Diving Expeditions, had to quit his local day trips, because not enough sharks were coming around.

“When we got into the biz 11 years ago an average day for us was 25 to 50 blue sharks,” Anes said. “The fellow who owned it before me back in the 80s, the average day for them they would see 100 to 150 sharks.”

Compare that number to a mere four or five sharks today. Now Anes takes divers to Guadalupe Island and beyond to find blues, makos and the endangered Great White.

Scientists estimate more than 100 million sharks are killed annually – about 270,000 per day. Among many factors, overfishing and accidental catches in drift nets are to blame. Even commercial fisheries thousands of miles away affect the number of sharks we see off our coast.

At the Scripps Institute of Oceanography, UCSD graduate student Daniel Cartamil and marine biologist Dr. Jeffrey Graham are studying sharks. Their research confirms what Anes has long suspected – sharks can’t keep up with the demand.

Not only is it putting a squeeze on his business, but it’s the long-term effects that could hurt everyone.

“The trend is the shark numbers and most of the fish numbers are vastly reduced, more than 25 or 30 years ago, even a dozen years ago,” Graham said.

Graham says there is an increasing demand for shark fin soup. The fins are cut off the shark’s body, in some cases while it’s still alive. The Shark Finning Prohibition Act makes finning illegal in U.S. waters, but outside of those boundaries some are still taking what they can get.

"It doesn't surprise me to hear that commercial shark diving boats are shutting down,” Cartamil said. “Until we get shark fishery management really under control, we're not going to see increases in those numbers."

Scientists say if you cut out the ocean’s top predator, you throw off the balance of a delicate system.

"They call out the weak, the sick, the old, they keep the ocean healthy – that's their job,” Cartamil said.

Something to keep in mind the next time you’re in the ocean: statistics show you are more likely to be mauled by a dog than a shark. Your drive to the beach is also far riskier than your swim.