These unknowns can be significant, says Ed Houde, a scientist at the University of Maryland Center for Environmental Science (UMCES) Chesapeake Biological Laboratory. Consider, for example, the numbers of fish discarded by all commercial fishermen in the Bay, let alone by recreational fishermen, where the impact of releasing fish may be just as great. What is the actual survival rate of those fish? What numbers should scientists use as they calculate "fishing mortality rate," a key variable in constructing fisheries models that resource managers employ to calculate a total allowable catch for stripers? Clearly a better understanding of the fate of discards in pound and gill net fishing, as well as in charterboat and recreational fishing, could affect conclusions based on these fisheries models.

Researchers and resource managers are no strangers to scientific uncertainty, and management decisions must often be made in the face of limited data and unanswered questions. The management of striped bass along the Atlantic seaboard provides a striking example.

Since the mid-1990s, commercial striped bass landings in Maryland have ranged from 1.6 to 2.5 million pounds a year. That wasn't the case some 20 years ago when, after years of record landings in the Bay and along the Atlantic coast, Maryland striper harvests plunged to a low of 446 thousand pounds.

Scientists searching for explanations for the decline looked at the impacts of water quality, of habitat loss, of contaminants, of overfishing. While all may have been implicated, research and monitoring pointed to overfishing as the key factor to address, partly because effective regulatory actions could be implemented quickly. Stripers were being heavily fished throughout their range - in the Chesapeake, where in any given year 70 to 90 percent of coastal stocks from Maine to North Carolina are spawned, during their exit out of the Bay, and in Atlantic coastal waters where they forage for four or five years before returning to upriver tributaries in the Chesapeake. In other words, many of the fish that produce the greatest number and highest quality eggs were being landed before they could ever get back, at least once, to their natal grounds.

According to Houde, researchers concluded that rebuilding large stocks of striped bass would require that a significant biomass of mature fish from different age classes - especially older and larger females with high reproductive potential - return to their spawning grounds.

Maryland and Virginia were already closing these grounds to fishing during the spring spawning season, but in 1985, Maryland went a step further and banned the taking of any stripers at all. The moratorium was followed by a coastwide strategic plan by the Atlantic States Marine Fishery Commission (ASMFC) to enable more mature striped bass to get back home. The plan established regulations that included raising minimum legal size (an index of age and maturity) and creel limits. Maryland lifted the ban in 1990 when monitoring gave strong evidence that "recruitment" of juvenile stripers was on the rise and different age classes were reaching their freshwater spawning grounds.

Today the ASMFC, with its state and federal representatives, sets a total allowable catch coastwide, allotting states from Maine to North Carolina a maximum quota (which they measure as "biomass"). Each state, including Maryland, then apportions that allotment among its fisheries. Bootie Collins, for example, is one of 157 pound netters in Maryland who in 2003 were allocated a total of 683,750 pounds. All who fish for stripers, whether gill netters, trawlers, hook-and-line fishermen or charterboaters, come under the limits of a specific allocation.

The restoration of striped bass has been hailed as a success story for rebuilding not only a major species, but a migratory one at that, a species that moves up and down the coast, returning to native spawning grounds in places like the Chesapeake Bay, Hudson River or Pamlico Sound in North Carolina, and crossing numbers of jurisdictional boundaries over numbers of years. Overcoming both scientific uncertainty and social and political obstacles to the development of a cooperative coastwide plan has made the striper a poster child for fisheries restoration. Can the striper's comeback serve as a management paradigm for rebuilding other species - by protecting spawning grounds and setting catch limits predicted to safeguard adequate reproduction?

Not wholly, says fisheries scientist David Secor, also at the Chesapeake Biological Laboratory (CBL). Controls on catch are obviously important, he says, and will have large effects, as evidenced in the striped bass recovery, but they are hardly the only answer. "They won't get us out of the hole we're in with sturgeon, with shad, and with oysters," he says. According to Secor, recovering these stocks will take a Bay that is more hospitable than it now is. It will take significant improvements in water quality, widespread recovery of submerged grasses and natural shoreline, which provide important habitat for young fish and molting crabs, and the rebuilding of active oyster reefs.

"We have to understand that we can't fix fisheries problems at every turn with increasing regulations," says Secor. "They are sometimes asked to do more than they can accomplish."

In a pound net, fish swim beside a long net called a "leader" that guides them into one or two traps called "hearts" and into the "pocket." Watermen gather the pocket net to haul in their catch. Drawing is from Ecology and Management of Marine Fisheries by George A. Rounsefell.

This page was last modified June 07, 2004

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