Concerns raised on number of adult female crabs

Va. agency's survey shows drop in bay spawning area

August 07, 2004|By Chris Guy | Chris Guy,SUN STAFF

In a summer when watermen are hauling in a surprisingly hefty crop of blue crabs, new information compiled by a leading Virginia scientist shows an alarming drop in the number of adult females in their spawning grounds at the mouth of the Chesapeake Bay.

Two months ago, a government report, based on four independent surveys, tallied a low but stable population of crabs throughout the bay. The good news, said most environmental experts, was that despite dire predictions for 2004, things hadn't gotten any worse in the past year.

But Romuald N. Lipcius, a researcher with the Virginia Institute of Marine Science, said the latest analysis of his agency's 2003 summer trawl survey, considered the most reliable gauge of female crab abundance, shows no change or a slight decline in spawning females in the area where all the bay's crabs produce their offspring.

"The spawning stock in the last few years has not rebounded and has not even stabilized," Lipcius said. "It appears to be declining further. If the trend from 1992 to 2004 continues, by 2006 or 2007 we could see a collapse of the fishery."

The numbers in recent years are hard to ignore, Lipcius said. In 1991, VIMS scientists estimated that 50 million to 60 million female crabs were in the spawning grounds near the Chesapeake Bay Bridge-Tunnel. Last year, he estimated, there were anywhere from "2 million to 10 or 15 million."

"We don't want to make a mistake and cry wolf, but we need to see if this year's data show the same trend continuing," said Lipcius, who is scheduled to begin surveying this month the sandy bottom in depths ranging from 6 feet to 100 feet to count the female crabs releasing millions of babies that will then be carried into the Atlantic.

June government study

The government study, released in June by the Chesapeake Bay Program partnership, found that the population of mature blue crab females is increasing after bottoming out in 2000.

The report - by agencies in Maryland and Virginia, scientists, and the National Oceanic and Atmospheric Administration - also concluded that juvenile crab numbers were increasing.

But Lipcius and other scientists said their count indicates that a three-year effort by Virginia and Maryland to reduce the crab harvest by 15 percent might not be working, as a major objective was to double the number of spawning females.

Year-round safeguard

Virginia has created a 930-square-mile crab sanctuary, mostly in the deepest parts of the bay, that prohibits harvesting from June 1 to Sept. 15. Female crabs outside the sanctuary are eight times as likely to be caught.

Lipcius said Virginia officials have begun to consider creating a year-round protected migration route that would safeguard females as they make their way to the mouth of the bay.

"The main catch in the fall is the `sook run,' the females that have mated and are making their way to the spawning ground," said William J. Goldsborough, senior scientist with the Chesapeake Bay Foundation. "I don't think it means the fishery is in danger of collapse, but it's telling us we're losing a significant number of females."

`Mother Nature'

Larry Simns, head of the Maryland Watermen's Association, said his membership is more skeptical than usual this summer as the experts search for an explanation of this year's crab bounty, an abundance that became obvious with a run of soft-shell crabs early in the season.

"They have to have doomsday if they're going to keep their grant money coming in," Simns said. "I don't know that it's a crisis even if the female numbers are down. Fewer females sometimes seems to signal an increase in the number of offspring, like Mother Nature trying to compensate. There's more little crabs in the bay now than I've seen in a long time."

Baltimore Sun Articles
|
|
|
Please note the green-lined linked article text has been applied commercially without any involvement from our newsroom editors, reporters or any other editorial staff.