by Alicia Pimental
August 09, 2011
A new scientific assessment of the Chesapeake Bay blue crab population shows that significantly more work needs to be done to rebuild the stock to sustainable levels.
The assessment, released by the National Oceanic and Atmospheric Administration, reveals that the blue crab stock was more depleted than originally thought and therefore will take longer to rebuild.
However, the stock has increased substantially in response to three years of management actions by Maryland, Virginia and the Potomac River Fisheries Commission, according to the assessment.
“The crab stock is improving throughout the Bay. Collectively, we have made a lot of progress over the past three years. But this new science indicates we still have a way to go to achieve our goal of having a biologically stable stock with a robust harvest,” said Jack Travelstead, Virginia’s Fisheries Chief.
The assessment sets a new healthy abundance level of 215 million female crabs, with overfishing occurring if 34 percent of the female crabs are harvested in a year.
Until now, fishery managers used an interim target of 200 million total adult crabs as the threshold of a healthy stock. Overfishing was considered to be occurring if 53 percent of adult crabs were harvested in a year. Regulations were established to meet these benchmarks, which were based on 2005 data.
For perspective, fishery managers have only come close to achieving the new assessment’s female abundance level three times during the past 22 years: in 2010, 1993 and 1991.
The new, more stringent assessment of the crab stock’s health will allow fishery managers to set more precise female harvest limits to fully rebuild the stock.
“This is a sea-change in how we will manage the fishery," Travelstead said, adding that Virginia is not likely to relax blue crab harvest restrictions in the near future.
“The new safe female abundance level and overfishing threshold will dictate how the fishery is managed in the years to come,” said Tom O’Connell, director of the Maryland Department of Natural Resources Fisheries Service.
The Chesapeake Bay Stock Assessment Committee will meet in September to consider the new assessment, examine data and provide management recommendations to Maryland, Virginia and the Potomac River Fisheries Commission.
The blue crab stock assessment took three years to complete and represents the best available science on the stock’s lifespan, gender, size distributions and reproductive capabilities.
Read and download the full blue crab stock assessment from the University of Maryland Center for Environmental Science’s website.