The blue crab population in the Chesapeake Bay jumped considerably in the past year, according to a survey released Monday.
The 2019 Blue Crab Winter Dredge Survey, which was conducted by the Maryland Department of Natural Resources and the Virginia Institute of Marine Science, showed that the Bay-wide blue crab population increased 60 percent from last year, to an estimated total population of 594 million crabs.
The two states have been conducting the survey since 1990 and natural resources officials review the results annually to craft management efforts across the jurisdictions. Biologists use dredge equipment to capture, measure, record, and release blue crabs at 1,500 sites throughout the Chesapeake Bay from December through March.
The rise in adult abundance of blue crabs was higher than anticipated given a poor influx of juveniles in 2017 and 2018, Maryland officials said – a sign that blue crab management has been successful at allowing more crabs to reach the spawning stock.
The adult female population climbed to 190 million, a 29 percent gain from 2018 and the adult male population increased to 80 million or 38 percent. Mild winter temperatures also helped increase both juvenile and adult blue crab survival rates.
The juvenile crab population also increased from 167 million in 2018 to 324 million this year. Since blue crabs spend the first part of their lives in the Atlantic Ocean they rely heavily on favorable currents, temperatures and winds to bring them into the Chesapeake Bay, where they grow and mature.
.“Today’s results are further proof and a shining example that our efforts to protect Maryland’s blue crab population, while ensuring the health of our state’s most important natural asset, have been successful,” Gov. Lawrence J. Hogan Jr. (R) said in a statement.
In 2018, baywide harvest was 55 million pounds, a slight increase from the 54 million pounds harvested in 2017.
While it’s hard to measure exactly how much of the population boost is directly attributable to government policy and how much is simply science taking its course, Genine McClair, manager of the blue crab program for the Maryland Department of Natural Resources, said in an interview that after a severe decline in the late 1990’s and early 2000’s, the crab population has generally been gaining since new management practices were instituted in 2008.
“That’s a sign to us that our management approach is working,” she said.
The Chesapeake Bay Foundation also applauded the survey results.
“While there are many variables that affect blue crabs, these strong numbers are not surprising after a mild winter and the good harvests reported by watermen last fall and this spring,” said Chris Moore, the group’s senior regional ecosystem scientist. “Good fisheries management and healthy habitat are the two big keys to a strong blue crab population.
“This is another year of positive news for crabs in the Bay thanks to wise management of the commercial and recreational fisheries for blue crabs. Increasing important blue crab habitat such as underwater grasses and oyster reefs also helps to boost the crab population. We hope the Bay states will continue their wise management policies and water quality investments in order to maintain these promising numbers.”