By Merrill Leffler and Jack Greer

Running down the center of the southern Bay, cutting a huge swath that nearly touches Virginia's Eastern Shore, lies a summertime crab corridor and sanctuary. From June to September, no one can catch crabs there - at least not legally - and so it becomes a veritable safe zone for blue crabs, especially female crabs ready to spawn.

Intense debate has circled the creation of this protected zone for crabs, which includes a sanctuary near the Bay's mouth and a mid-Bay corridor (in waters generally 35 feet deep or more) that reaches to the Maryland-Virginia line. Crabbers, cut off from fishing grounds, complain about its length and breadth. Some - especially in Maryland - complain that the sanctuary does no good, since crabs and crabbers don't use these deeper waters in summer anyway. Welcome to the world of marine protected areas, zones designed to preserve specific habitats and marine populations, and guaranteed to stir local controversy.

"Say No to NOAA," signs once read in the Florida Keys, where debates have raged over marine protected areas - a reflection of the depth of dissent over this practice. In the Chesapeake, where local jurisdictions hold sway over such inshore fisheries as oysters and blue crabs, the states of Maryland and Virginia, along with the Potomac River Fisheries Commission, control the establishment and management of protected areas, and also take the heat.

Though often contentious, the idea of protected areas is not new. When mapping oyster bars back in the 19th century, both Maryland and Virginia began to move toward the concept of zones - of defining areas for wild bars and for potential leased bottom. Similarly, when Maryland stopped the dumping of chlorine into striped bass spawning areas during spring, these areas became, in a sense, protected. And when a 1985 moratorium shut down fishing for striped bass in the Bay altogether, the Chesapeake itself became a kind of marine protected area, at least for striped bass.

Now the question arises of whether placing certain areas off-limits, especially for fishing, can provide a key tool for managing fish and shellfish in the Chesapeake. In addition to Virginia's blue crab sanctuary, Maryland has created a series of oyster sanctuaries, some to be harvested after a set number of years, others to be preserved for the long haul, to protect brood stock and to give native oysters a chance to adapt - however slowly - to the killing pressure of oyster parasites.

Proponents of such protected areas argue that they can help bring back a fishery. Researcher Rom Lipcius, well-known crab ecologist at the Virginia Institute of Marine Science, shows survey results that verify his claim that large numbers of female blue crabs reside in Virginia's deep-water sanctuary during the summer months. By protecting them from harvest, he argues, we greatly improve their chances of spawning, and of maintaining - or even increasing - the Bay's crab stock.

"Rather than tell people how much they can fish or catch, which is the usual way we regulate," says Ed Houde, "maybe we should at times consider the habitat as space that fish occupy and manage regions recognizing the heterogeneity of the ecosystem and estuary."

"We have a lot to learn about spatial management," says Houde, "but in general we know that if you don't fish in a portion of an area, you have more fish and they're bigger." This is not necessarily a trivial conclusion, says Houde, who chaired a National Academy of Sciences panel that recently published Marine Protected Areas: Tools for Sustaining Ocean Ecosystems. "If you have more fish and they're bigger, you've built up the spawning stock biomass and thus increased the stock's fecundity and age structure. So you have achieved those objectives, in some instances more efficiently than if you tried to regulate how much people catch."

Many advocates of marine protected areas think that you have to set up marine reserves that close areas from all exploitative activity to achieve their full benefits, which is to help protect the overall productivity of an ecosystem, says Houde. For a fishery manager, how much of an area one protects depends on what the sanctuary or reserve is expected to do.

"How much of an ecosystem should we put in a marine protected area?" Houde asks. "It's a question that's dogged a lot of people." The answer seems to be that if it is used as the primary way to manage a marine ecosystem for fisheries or otherwise, maybe 30 to nearly 80 percent. That is, of course, unrealistic, especially in any conventional fisheries management context. "Fishermen, commercial and recreational, would go crazy!" Houde says.

As he points out, however, combining conventional management tools along with protected areas can lead to much more acceptable approaches that require protection of less expansive areas. Combining area closures with seasonal closures, as is done in protecting spawning striped bass in the Bay, is an application of spatial-temporal management that is already applied as a supplement to conventional fisheries management.

Ultimately, Houde says, any decision about whether to implement protected areas management depends on what other effective mechanisms managers have in place and what specific goals are set. After all is said and done, he says, decisions about whether to adopt extensive spatial management measures rest on the goals and expectations of stakeholders and managers.

This page was last modified February 06, 2004

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