Blue Crab Numbers Down But Population Remains Healthy

The Chesapeake Bay Program has released the 2021 Blue Crab Advisory Report, which finds that the overall Chesapeake Bay blue crab population is not being overfished and is not depleted. Experts from the Chesapeake Bay Stock Assessment Committee reviewed the results from the annual bay-wide winter dredge survey (released in May 2021 by the Maryland Department of Natural Resources and the Virginia Institute of Marine Science) and harvest figures from the previous seasons to provide an in-depth picture of the Chesapeake’s blue crab population and to make suggestions for any needed changes to regulations.

The winter dredge survey found that the blue crab population (males and females alike of all ages) in the bay — which varies naturally from year to year — decreased from 405 million in 2020 to 282 million in 2021. Experts attribute this decline to be in large part due to the juvenile blue crab population — crabs that will grow to harvestable size next year — which is estimated to be 86 million, down from 185 million in 2020. Managers will monitor the status of these populations over the summer, adjusting regulations if needed.

The stock of male adult blue crabs (ages 1 and up) was estimated to be 39 million in 2021, a decline from the approximately 79 million in 2020. In 2021, the population estimate of adult females increased to 158 million from 141 million in 2020. This number is above 72.5 million, which is the minimum acceptable level for female blue crabs in the bay, but lower than the target of 196 million. In the 2020 blue crab fishing season, 19% of all female crabs were harvested — safely below the science-based target (28%) and threshold (37%) levels for the 13th consecutive year. Resource managers focus on maintaining a healthy stock of female crabs to ensure continued resiliency of the population in this and future years.

The 2021 advisory report recommends:

• Researchers should explore the environmental factors that may contribute to the highly variable nature of the blue crab population.
  
  
• The Maryland Department of Natural Resources, Potomac River Fisheries Commission and Virginia Marine Resources Commission should implement programs to track commercial and recreational harvest more accurately, including the use of electronic reporting systems.
  
  

The Blue Crab Advisory Report is developed by the Chesapeake Bay Stock Assessment Committee, a group of experts from state and federal agencies and academic institutions. The blue crab fishery in the Chesapeake Bay is managed by the Maryland Department of Natural Resources, Virginia Marine Resources Commission and Potomac River Fisheries Commission.