Shark population decreases in bay Sharp drop blamed on commercial fishing and trophy hunters

September 01, 1996

GLOUCESTER POINT, Va. - It may not worry nervous LTC swimmers much, but shark populations in the Chesapeake Bay are dropping sharply, a shark researcher says.

Jack Musick of the Virginia Institute of Marine Science says shark fishing has depleted the numbers of some shark species in the region by 80 percent to 90 percent.

"Most of our fisheries have really been mining operations," Musick said. "This is the best indication we have of the true magnitude of the crash that's occurred."

That crash is measured in the number of sharks Musick catches for every 100 baited hooks he sets. In the mid-1970s, Musick would catch nearly 19 sharks per 100 hooks - mostly sandbars, Atlantic sharpnoses, duskys and sand tigers.

By 1991, that had dropped to fewer than five sharks per 100 hooks, where it remains today. And the sharks he catches have gotten smaller, he says.

Sharks had been holding their own against humans, the only predator above them in the food chain, until the release of the movie "Jaws" in 1975.

Suddenly people wanted to catch sharks from piers and charter boats, and shark tournaments drew huge crowds. By the early 1980s, large, trophy sharks like the dusky began to decline, Musick said.

Then sharks began appearing on menus in the United States, while demand for shark fins exploded in Asia, where, prized as an aphrodisiac, they are served in soups.

Commercial fishermen began going after sharks in greater numbers, using the same longlines that Musick uses in his research.

Sharks are particularly vulnerable to this kind of pressure because they are slow to reproduce.

Most other fish mature in a few years, then spew out fertilized eggs by the tens or hundreds of thousands. By contrast, sandbar sharks, the most common in the Chesapeake Bay, take about 15 years to reach reproductive age and then have litters of eight or nine pups every other year.

"That's an incredibly low reproductive rate," Musick said.

In 1990, the Virginia Marine Resources Commission moved to protect sharks by prohibiting commercial fishermen from using longlines and limiting their landings to 7,500 pounds of carcasses and 750 pounds of fins per day.

Virginia also limited recreational fishermen to one shark per day.

A few years later, the National Marine Fisheries Service adopted a shark-management plan for the Atlantic and Gulf coasts that placed commercial fishing quotas on large coastal and open ocean sharks.

But the federal regulators are too optimistic about the recovery of the sharks and set the quotas too high, Musick contends.

The precipitous crash of shark populations has leveled off, he said, "but there really is no rebuilding going on. And our models show there won't be unless they cut the quotas by 50 percent."

Pub Date: 9/01/96

Baltimore Sun Articles
Please note the green-lined linked article text has been applied commercially without any involvement from our newsroom editors, reporters or any other editorial staff.