RICHMOND, Va -- A preliminary scientific study shows that Chesapeake Bay's blue crabs are not being overfished, casting doubt on the need for catch restrictions protecting the bay's most important species.
The study, presented here yesterday to a joint meeting of Maryland and Virginia officials, was immediately challenged by other scientists, one of whom presented contradictory research of his own.
The clash of studies clouded the beginning of a pioneering effort by Maryland and Virginia to reach agreement on new regulatory measures to protect crabs.
Last week, Maryland curtailed the days and hours for commercial and recreational crabbing and shortened the season by 45 days. State officials said they planned other conservation measures next year and called on their Virginia counterparts to follow suit.
John R. Griffin, Maryland's natural resources secretary, said after the meeting that he did not think the new study conflicts with his agency's action to stem a perceived decline in spawning female crabs.
"That's good news," he said, "But that doesn't mean there aren't things we need to do to bolster the fishery. The question is how far do we go, not whether we do anything."
The finding that crabs are not being over-harvested was the preliminary result of a comprehensive new study of the Chesapeake's crab stock being done by Maryland and federal biologists.
"This is brand-new scientific territory," said M. Elizabeth Gillelan, bay program director of the National Oceanic and Atmospheric Administration, which is collaborating with Maryland's Department of Natural Resources on the study.
In a computer-assisted analysis of catch records and scientific surveys dating to the 1950s, researchers have found no evidence that crabbing to date has depleted the population to where it can not sustain itself. Three mathematical models of the bay's crab stock fail to show that harvests have depleted female crabs enough to harm reproduction.
But the study is not finished, and the findings are so fresh that Anne Lange, the NOAA biologist who presented them, said researchers were reluctant to publicize them without further scrutiny. Final results are due by the end of the year.
Romauld Lipcius, chief crab researcher at the Virginia Institute of Marine Science, questioned the findings, which rely in part on surveys his lab has done. He contended that his own research shows that the bay's crab stock was reduced sharply by Tropical Storm Agnes in 1972 and has failed to rebound since then, in large part because of fishing pressure.
Juvenile crabs have increased in abundance as bay grasses have returned to the bay since the storm, Dr. Lipcius said, which is an indication that efforts to improve water quality in the bay are working. But he said surveys have not detected a corresponding increase in adult crab abundance.
The bay's crab population is not on the verge of collapse, Dr. Lipcius said, but current fishing effort is preventing the stock from returning to its previous abundance. And another storm could devastate the bay's crabs.
"This is the time to act to prevent a crisis," Dr. Lipcius said.
The rosier view of the bay's crab stocks was welcomed by Virginia fisheries regulators, who have shown no inclination so far to match Maryland's move this month to reduce commercial and recreational catch.
"I think we're on the right course," said William A. Pruitt, Virginia's commissioner of marine resources. Though commercial crab harvests are down, he noted that Virginia has already imposed restrictions.
Virginia last year expanded "no-harvest" sanctuaries for spawning female crabs near the mouth of the bay, and has imposed restrictions on commercial and recreational crabbers, which officials say should reduce catch.
A Virginia recreational crabber testified that he finds fewer crabs in his pots and that he and others will press the legislature to act further if regulators don't. "I don't care what statistical data you come up with," said James Gordon of from Kilmarnock. "The crab population is down, period."