Fish stocks fare better in bay than sea

Stewardship more difficult in oceans, where `collapse' is seen

November 03, 2006|By Rona Kobell | Rona Kobell,Sun reporter

The Chesapeake Bay's signature seafood species are in better straits than ocean fish because state regulations help to prevent overfishing. But experts say the bay's rockfish, oysters and crabs continue to face a mighty struggle against pollution and loss of habitat.

A study in the journal Science, which will be released today, warns that marine life in the ocean is being overfished at such a rapid rate that all species are heading for a "global collapse" by the year 2048.

Ocean species are difficult to manage because they cut such a wide swath across the globe, populating the waters of many different countries. In the Chesapeake Bay, however, fisheries managers in both Maryland and Virginia have a lot of control.

FOR THE RECORD - An article in yesterday's editions incorrectly reported how many people hold oystering licenses in Maryland. The correct number, according to the state's Department of Natural Resources, is 530.
The Sun regrets the error.

"We have several major issues here, and the biggest is not over-fishing," said Ann Swanson, executive director of the Chesapeake Bay Commission, which helps set fishery policy in the region. "We don't just allow cowboys in the bay, fishing endlessly. It's highly regulated."

Scientists with Maryland's Department of Natural Resources work closely with the Atlantic States Marine Fisheries Commission to assess the population of various species along the coast. When the numbers look grim, the state institutes controls.

In the late 1980s, Maryland's rockfish population, also known as striped bass, had reached such a crisis, and the state imposed a moratorium on catching the fish. The next decade, the species was considered restored, and the ban was lifted.

Four years ago, when the blue crab population hit historically low levels, state regulators shortened the season and the hours per day that watermen could crab. They also tightened size limits to protect smaller crabs.

The rockfish's rebound has become a national success story. That it was necessary is "indisputable," said Donald F. Boesch, president of the University of Maryland Center for Environmental Science.

Boesch is less convinced that the blue crab restrictions will jump-start as big a turnaround.

"In the blue crab, I think the jury is still out, although the signs we're seeing do show that it was a prudent management strategy."

Howard King, director of fisheries for the DNR, said he believes shortening the crabbers' day has made the biggest difference. Now, he said, the population is stable, but at a much lower number than it was historically.

"We have to remain vigilant and look for other ways to sustain the population," King said. "We need to make sure we have enough females in the bay."

While overharvesting was once a problem for the bay's oyster stocks, that isn't the issue anymore. Disease has left the bivalve population at just a fraction of what it was two decades ago; only a few dozen watermen bother to hold an oystering license.

Pollution in the bay has been a far more intractable problem than overfishing, authorities say.

Population growth has led to increasing development in the watershed, which means more impervious surface and more runoff from storms. Sewage treatment plants and fertilizers discharge large amounts of pollution into the bay, creating algae blooms that block sunlight and kill grasses that are habitat for crabs and fish. Low oxygen conditions in the bay's deep waters suffocate the animals that crabs eat.

The Science study, which included research from an international group of ecologists, suggested fisheries managers take an ecosystem-wide approach to regulating species instead of the one-species-at-a-time method used for decades.

Many scientists in the Chesapeake Bay region have been advocating such an approach, especially with regard to menhaden.

For years, a national company has been taking millions of pounds of the small baitfish out of the Chesapeake's mouth in Virginia. Yet, researchers haven't proved the species was overfished because they were looking at the numbers coastwide, not just in the bay. And they weren't taking into account how menhaden, a prime food for rockfish, were affecting larger fish.

"How can you manage striped bass if you're not looking at what they eat, what eats them and where they live?" Swanson asked.

Bay researchers are moving to an ecosystem-based model, but it takes time to change entrenched policies, Swanson said. She said the Science study is another indication that time is running short.

"The report sends a resounding signal that we are in charge of our own destiny," Swanson said. "We better manage our fisheries for all they're worth, because you can lose them."

rona.kobell@baltsun.com

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