Adult female blue crab abundance rises 92 percent in 2016

The Chesapeake Bay’s adult female blue crab population has increased 92 percent since the population was surveyed last winter. While the current adult female blue crab abundance of 194 million is well above the overfishing threshold, it remains below the 215 million abundance target.

Maryland and Virginia estimate the Bay’s blue crab population through an annual winter dredge survey. Over the course of three and a half months, scientists visit 1,500 sites around the Bay, using metal dredges to pull up crabs over-wintering in the mud.

Results of the 2016 winter dredge survey show the Bay’s total blue crab population has increased from 411 million to 553 million since last winter. Results also show the number of adult females has risen from 101 million to 194 million. The number of juvenile crabs has increased from 269 million to 271 million, which is just above the long-term average.

“The crab stock has been on a rollercoaster for most [of] the last decade,” said Virginia Marine Resources Commissioner John M.R. Bull in a media release. “We’ve seen a few great years of reproduction followed by awful years of abundance. Two years does not make a trend, and this news inspires both wary optimism and cautious management.”

In the short term, Maryland officials do predict a good crab season. “Due to a milder winter, favorable currents and tides, and wise Bay-wide management measures, the Maryland crab population continues to rebound and strengthen,” said Maryland Department of Natural Resources Fisheries Service Director Dave Blazer in a media release. “With an increase in abundance and steady recruitment, we fully anticipate a robust crab season this year.”

The Chesapeake Bay Program tracks the adult female blue crab population as an indicator of Bay health, and in the Chesapeake Bay Watershed Agreement committed to maintaining a sustainable blue crab population based on a target of 215 million adult females. The Chesapeake Bay Stock Assessment Committee (CBSAC), which includes scientists and representatives from states, academic institutions and the federal government, will use this data to make recommendations on sustaining the blue crab population in its 2016 Blue Crab Advisory Report, expected to be released this summer.

Learn more about the winter dredge survey in Maryland and Virginia.