The Atlantic States Marine Fisheries Commission has adopted a new plan for menhaden that removes industry representatives from the decision-making committees and promises to better account for the ecological role played by the fish.

The plan, adopted in April, comes amid new evidence that the fish population is at its lowest level in three decades. Preliminary estimates from the National Marine Fisheries Service indicate the stock size has fallen more than 60 percent in the past three years.

Menhaden are a small, oily fish, but they play a big economic and environmental role in the Bay and along the coast. They support the largest commercial fishing in the Chesapeake — measured by weight — and one of the coast’s largest fisheries.

Generally, one of the most abundant species, menhaden are an important source of food for bigger predators, such as striped bass, bluefish and weakfish. It is also a filter feeder, and large schools of the fish can consume huge amounts of algae, improving water quality.

As the menhaden stock declines, the management of the fishery has become increasingly controversial. Recreational fishermen and others complain that the commercial fishery catches too many menhaden, reducing the food supply for striped bass and other species.

Others, including the Bay Program, have called for managers to take into account its ecological role. Some have suggested that a healthy menhaden stock could remove large amounts of nutrients from the Bay through their consumption of algae.

Responding to those concerns, the Atlantic States Marine Fisheries Commission adopted a new management plan after nearly two years of discussions, comments and review. The ASMFC, which represents all East Coast jurisdictions, is responsible for writing binding plans for all species that cross state lines.

The new plan restructures the technical committee and management board responsible for overseeing menhaden by removing industry representatives who previously had accounted for half the membership of those panels.

No board or technical committee for any other ASMFC species contained industry representatives, and complaints about their participation was the top concern voiced in public comments.

The plan also sets a new overfishing definition that will be used in guiding future management actions. The new definition contains both a fishing mortality target for the fishery as well as a threshold that is not to be exceeded. Right now, the fishing mortality rate is between the threshold and the target.

It also sets a target and a threshold for the spawning stock biomass, an estimate of the weight of the fish of reproductive age, which is considered a gauge of the reproductive potential of the stock.

Left unclear is exactly what happens when the population hits the targets, or is in the “gray area” between the thresholds and targets.

“It doesn’t have a specific prescription for what you do under that situation,” said Bill Goldsborough, senior scientist with the Chesapeake Bay Foundation and a member of the ASMFC’s Menhaden Management Board. “It didn’t go as far as some people wanted with respect to that type of circumstance.”

Overall, Goldsborough commended the plan for being comprehensive in its goals and objectives, but said it was too vague about how to attain them. As a result, he said it may need to be updated with more specific management actions “perhaps within a year.”

The plan calls for improved ecological management of menhaden to take into account the roles it plays as a filter feeder and as food for other fish, although it doesn’t say exactly what should be done.

“We’re in a holding pattern,” said Joe Desfosse, the ASMFC’s menhaden plan coordinator. The commission, he said, is waiting for results from ongoing research on multispecies interactions between menhaden and striped bass, weakfish and bluefish.

That information will be factored into updates to the plan as it becomes available.

Goldsborough said the plan takes the commission in the right direction, noting that it is the ASMFC’s most assertive effort date dealing with multispecies issues, even if it did not go as far as many would have liked. “The ASMFC is going to grow a little bit in a new direction with the Menhaden Management Plan, and it’s a good direction to go,” he said.

Meanwhile, new figures indicate that the menhaden stock has continued its sharp decline of recent years.

In a preliminary assessment of the stock’s health, Doug Vaughan a National Marine Fisheries Service biologist, said the menhaden spawning stock has fallen to about 30,000 metric tons.

That’s below the target of 37,400 metric tons established in the new plan, but above the threshold of 20,570 metric tons — a minimum level that is supposed to trigger management action.

That was also a continued decline from last year’s estimate of 32,800 metric tons, and a drop of more than 60 percent from the 87,000 metric tons estimated in 1997.

Vaughan also said his preliminary estimate for fishing mortality puts it slightly above the target, but still below the critical threshold level.

But Vaughan, who makes an analysis of the stock every year, said he believes the menhaden problem is not overfishing, but continued poor “recruitment” — a measure of young fish that survive to join the population.

Vaughan said that recruitment in the menhaden population declined before the spawning stock fell — an indication that the primary cause of the decline has been related to reproduction, not fishing.

“The problem is that something is causing real poor recruitment, primarily in the Chesapeake Bay, but we’re starting to see some problems in North Carolina now,” Vaughan said. “But in southern New England, they’ve seen more than they’ve ever seen before. They are producing a lot of young up there.”

The Bay and southern areas tend to be the most important areas for menhaden recruitment.

Although the spawning stock is now below ASMFC’s target, it is twice the record lows seen in the late 1960s and early 1970s. “We haven’t gotten down there yet, and I would rather that we didn’t,” he said. “I think the stock has problems.”

Jim Price, president of the nonprofit Chesapeake Bay Ecological Foundation, contends that the ASMFC should move to curtail fishing pressure because of the low population.

Price, who has criticized menhaden management for years, agreed that recruitment has been low, but argues that action should be taken to curb the commercial catch as well. Recent catches have fallen 70 percent below the 45 year average, Price said — an indication that the stock is “collapsing.”

“Management decisions are needed to reverse the long-term decline of this valuable resource,” he said.

In particular, he criticized the increased catch of fish less than a year old in the commercial fishery. Those young fish accounted for 12 percent of the catch last year, and 18 percent in 1999, whereas they made up only 3 percent of the catch from 1995–97, according to NMFS figures.

The ASMFC has recommended that fishing operations avoid those small fish because they are too young to have had a chance to reproduce and help build up the stock, although the new plan does not yet prescribe specific measures to conserve age 0 fish.

Desfosse said the catch has declined primarily because of a drop in the market for menhaden products. Menhaden are used primarily for oil and animal feed. Last year, he said, the fishing effort was 70 percent below the levels seen in the 1970s and 1980s.