A Baby Boom Of Blue Crabs
Bay Rules May Have Aided 43% Increase
Saturday, April 18, 2009
The number of blue crabs in the Chesapeake Bay increased about 43 percent last year, according to survey data released yesterday, and scientists said it was probably a sign that measures taken to protect the beleaguered bay icon are working for now.
A baywide survey this winter, in which scientists counted crabs by dredging them out of their sandy burrows, yielded a population estimate of just more than 400 million. That was up from 280 million last winter.
Blue crabs are a species prone to explosive swings in population, so there is no guarantee that the growth will continue. But scientists and state officials said they were encouraged by the results, especially by the near-doubling in the number of adult females.
"We fully expected some kind of an increase. Now, the increase that we got, right now, was a little higher than we expected," said Rom Lipcius, a professor at the Virginia Institute of Marine Science who worked on the survey. "What that means is that the management actions worked so far, and I want to emphasize that they worked so far."
The population numbers are still far below where they were in the early 1990s. In 1991, there were an estimated 828 million crabs in the bay. Since then, the species has suffered because of declining water quality and heavy fishing from watermen, who have come to focus more on the crabs while the Chesapeake's oysters, their other traditional income source, have dropped to historic lows.
Last year, Maryland and Virginia took major steps to cut back on the harvest of female crabs, which produce the eggs that could rebuild the Chesapeake's population. The states limited the number of female crabs that could be taken at certain times and banned Virginia's traditional "dredge" fishery, in which watermen scraped the crustaceans out of their winter burrows.
Those moves came at a serious cost to the bay's watermen: The federal government declared their fishery a disaster last year.
Lipcius said the end of the dredge fishery -- which took females before they were able to release their eggs at the bay's mouth -- had been the major reason for the rebound.
But he said he wants to see at least three more years of encouraging results. "Then I would start to feel comfortable about relaxing some of the regulations."