2020 Blue Crab Advisory Report

Description

The Chesapeake Bay Stock Assessment Committee (CBSAC) meets annually to review the results of the Chesapeake Bay blue crab surveys and harvest data, and to develop management advice. CBSAC adopted the Bay-wide Winter Dredge Survey (WDS) as the primary indicator of blue crab population health in 2006 because it is the most comprehensive and statistically robust of the blue crab surveys conducted in the Bay. Based on survey estimates, the total abundance of all crabs (males and females of all ages) was estimated at 405 million crabs in 2020. Recruitment, or the number of age 0 crabs (less than 60 mm or 2.4 inches carapace width), was estimated as 185 million crabs in 2020. Approximately 141 million age 1+ female crabs were estimated to be present in the Bay at the start of the 2020 crabbing season, which is above the abundance threshold of 70 million crabs, but below the target of 215 million crabs. The 2011 benchmark stock assessment recommended a control rule based on biological reference points for the female component of the population. The percentage of female crabs (ages 0+) removed by fishing (exploitation fraction) in 2019 was 17%. This exploitation fraction is below the target of 25.5% and the threshold of 34% for the 12th consecutive year since 2008. Therefore, overfishing is not occurring and the population is not depleted.

Based on analysis of the 2020 winter dredge survey results, CBSAC recommends that substantial changes in management are not necessary. CBSAC further recommends that the jurisdictions implement procedures that provide accurate accountability of all commercial and recreational harvest moving forward, as this is an important component for accurately accessing stock health.