5 new management plans to take fish-eye view of ecosystem
Alarmed at the decline of New England fisheries more than a century ago, Congress reacted by forming the nation’s first resource management agency: the U.S. Commission of Fish and Fisheries.
In 1871, President Ulysses Grant appointed its first commissioner, Spencer Baird, a scientist from the Smithsonian Institution. He was charged with determining the reasons and remedies for the declines.
Baird, who established what would become the Woods Hole Laboratory, quickly concluded that this was no easy task, and most of his initial management recommendations failed. Understanding fish populations, he wrote, “would not be complete without a thorough knowledge of their associates in the sea, especially of such as prey upon them or constitute their food.”
Fishery managers around the Bay these days may be feeling nearly as overwhelmed as Baird. By the end of this year, they are charged with drafting the Bay’s first five ecosystem-based fishery management plans.
Those plans will go beyond the bounds of traditional management plans, which typically focus on setting maximum sustainable yields by regulating how many fish may be caught, when they may be caught and with what gear. The new plans will discuss important habitats needed for the fish or shellfish in question, as well as their influence on the food web.
Ecosystem planning has become a popular buzz word for managers. The U.S. Commission on Ocean Policy, appointed by President Bush, emphasized in its report last fall that coastal systems, including fisheries, “should be managed to reflect the relationships among all ecosystem components.”
But the task is not trivial. Hardly any ecosystem plans for fisheries exist anywhere. In part, that is because the concept itself is staggering. The ecosystem that affects Bay fisheries includes a 64,000-square-mile drainage basin and marine areas that extend far into the Atlantic Ocean.
“We’re learning ahead of the curve,” said Steve Giordano, a fisheries biologist with the National Oceanic and Atmospheric Administration’s Chesapeake Bay Office, who is among the teams of scientists writing the first five plans. “But ultimately, this is where everyone is going.”
The plans, due by the end of the year under the Chesapeake 2000 agreement, will cover striped bass, menhaden, blue crabs, oysters and alosids (shad and herrings).
The guiding principles for the plans were set forth last year in a report by a team of scientists, supported by NOAA’s Bay Office, “Fisheries Ecosystem Planning for Chesapeake Bay.” The 360-page report offered a sweeping strategy to coordinate and improve the way fish—and their habitats—are managed in the Bay.
The new approach calls for casting the management net over the entire ecosystem—from habitat in the farthest headwater stream to water quality at the Bay’s mouth, and possibly beyond—and involving new agencies in the effort.
As Baird recognized more than a century ago, it’s not just fishing pressure that affects fish stocks. Poor water quality, land uses that degrade habitat and other factors play a significant role in determining fish abundance.
For example, blue crab abundance in the Bay has been at low levels for years. Management has focused on reducing harvest pressure to protect enough spawning crabs to maintain the population. But scientists say part of the problem is that the Bay has lost huge amounts of habitat, such as underwater grass beds, which serve as nursery areas for young crabs.
“You can decrease fishing pressure all you want and you won’t have a viable population if you don’t have a place for them to spawn and grow up,” Giordano said.
Likewise, the presence of large amounts of roads and other impervious surfaces near a spawning area can have big impacts. The pavement warms rainwater, which affects spawning, and the runoff can carry a host of chemical contaminants.
That doesn’t mean the new plans will neglect traditional catch limits. “Nothing about these plans removes our needs for managing the fisheries traditionally,” Giordano said. “It just recognizes there is more affecting the stock.”
For each of the target species, the plans will discuss key predator and prey interactions and use computer models to suggest how a change in abundance of the target species may affect others.
The plans will seek to estimate the number of fish being caught, not only by commercial and recreational activities, but also in by-catch, discards and other fishery-related activities. They will identify the the location of important habitats, both in and out of the Bay and potential threats to those habitats. They will also estimate whether current restoration efforts are adequate to sustain the fishery.
The plans will also look at non-fishery human impacts, such as the effects of erosion, stormwater runoff on critical habitat areas, boat pollution, sewage dumping—even airborne mercury pollution from power plants.
Fishery scientists acknowledge that their plans are unlikely to singlehandedly curb pollution from power plants, or result in sweeping policy changes. But by broaching such issues in the plans, they hope to begin building awareness among various agencies and groups that their actions have impacts on fish.
“Habitat regulations are typically out of the hands of fishery managers,” said Nancy Butowski, a fisheries scientist with the Maryland Department of Natural Resources who chairs the Bay Program’s Fisheries Management Planning and Coordination Workgroup. “By bringing other agencies to the table, we hope to generate their interest, and a means to move those issues forward.”
To help make that happen, it’s anticipated that the Chesapeake Executive Council—which includes the governors of Maryland, Virginia and Pennsylvania; the EPA administrator; the District of Columbia mayor; and the chairman of the Chesapeake Bay Commission, which represents state legislatures—will formally endorse the 360-page ecosystem planning document at their meeting later this year.
Still, fishery managers stress that the ecosystem plans will be, in the words of one, more evolutionary than revolutionary. Instead of trying to describe everything within the Bay and its watershed that could impact a species, the initial plans will put most of their focus on the closest habitat and food web relationships.
“To be effective, we are going to have to focus on some key processes rather than just describe the whole complex of variables within the ecosystem,” Butowski said.
Besides putting fisheries on the radar screens of nontraditional agencies, the plans may have practical implications—beyond setting catch limits—such as helping to target where restoration efforts should be priorities.
For instance, tributary strategies written by the states may say how many miles of riparian forest buffers should be planted along a given river to meet Bay Program nutrient and sediment goals, but the fishery management plans may say where those buffers should be planted to provide the most benefit for fish.
Instead of focusing on maximum sustainable catch for each species, the plans will likely take a closer look at how different catch levels affect not only the target species, but also predator and prey species. Will too many striped bass affect blue crab abundance? Would more crabs eat too many oysters? Are there enough menhaden to feed striped bass?
The Atlantic States Marine Fisheries Commission, which regulates migratory fish along the East Coast, recently indicated that it may cap menhaden catches within the Bay, in large part because of concerns that there are too few menhaden to feed the Bay’s brimming striped bass population.
Population modeling being done for the new plans may suggest how those caps should be implemented in the Bay, and how to optimize the balance between menhaden, striped bass and other fish. “Chesapeake Bay plans will allow greater detail, and a better pathway to implementation, than can come from an ASMFC plan,” Butowski said.
While other management agencies are interested in taking ecosystem factors into consideration, scientists say it is easier for Bay Program plans to take the first step, in large part because they are voluntary.
The ASMFC has regulatory authority to manage migratory species within three miles of the coast. Beyond that, management responsibility rests with a series of regional fishery councils, which include representatives from states and federal agencies.
Because ecosystem and multispecies considerations are relatively new—and harder to quantify—concepts, those agencies are more susceptible to lawsuits if they veer far from traditional fishery management goals in setting enforceable catch limits.
“The commission and the council are a lot more cautious,” said Derek Orner, a fisheries biologist with NOAA’s Chesapeake Bay Office who works with both the commission and the councils. By contrast, he said, the Chesapeake plans have more flexibility to make recommendations. “What we can really do at this point is push new approaches, and help change the mindset for management.”
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