The abundance of spawning-age female blue crabs in the Chesapeake Bay decreased to 97 milllion in 2012, compared with 190 million in 2011.
The 2011 benchmark assessment recommended establishing a threshold number of 70 million female spawning-age crabs and replacing the interim target of 200 million male and female spawning-age crabs with a target of 215 million female spawning-age crabs. Approximately 97 million female age 1+ crabs were estimated to be present in the Bay at the start of the 2012 crabbing season. This number is below the recommended target but still above the new threshold. The 2012 estimate of female age 1+ crabs represented a significant drop from the over-wintering population of 190 million in 2011. However, the 2012 estimate is within the range of values observed for the 13 year period prior to implementation of the female-specific regulations being put in place.
April 2013: The Chesapeake Bay winter dredge survey is an annual count of the Bay’s blue crab population, and a critical component of blue crab management. The information gathered on abundance, young-of-the-year and spawning stock—those crabs that will mature enough to reproduce during the upcoming year—allows fisheries managers to set commercial and recreational harvest limits for the season ahead.
Closed captions: http://www.youtube.com/watch?v=28mvEE7ydXA
Produced by Steve Droter
Music: “Elle Aime Ca” by Löhstana David
Perhaps no species is more closely associated with the Chesapeake Bay than the blue crab. It is estimated that one-third of the nation’s blue crab catch comes from the Bay.
Because they reproduce by the millions and eat virtually anything, crabs are one of the Bay’s most hardy species. Good water quality and adequate habitat are important for the crab’s continued health.
A target abundance of 215 million spawning-age female crabs was adopted in 2011.
Long-term trend (1990-2012)
During this time period, spawning-age female blue crab abundance averaged 117 million, with a minimum of 56 million and a maximum of 251 million.
Short-term trend (2003-2012)
During this time period, spawning-age female blue crab abundance averaged 125 million, with a minimum of 84 million and a maximum of 251 million
Change from previous year (2011-2012)
The abundance of spawning-age female blue crabs in the Bay decreased to 97 million in 2012, compared with 190 million in 2011.
The 2012 Chesapeake Bay Blue Crab Advisory Report recommends the following for female crabs:
The Blue Crab Advisory Report, developed by the Chesapeake Bay Stock Assessment Committee (CBSAC), is based primarily on data from the Bay-wide Blue Crab Winter Dredge Survey and on annual estimates of blue crab harvest. In 2006, CBSAC adopted the Bay-wide winter dredge survey as the primary indicator of blue crab stock status because it is the most comprehensive and statistically robust of the blue crab surveys conducted in the Bay.
CBSAC includes fisheries scientists from universities, the states of Maryland and Virginia, and NOAA’s National Marine Fisheries Service.
Based on recommendations from the 2011 Chesapeake Bay Blue Crab Advisory Report, this indicator now tracks spawning-age female abundance in relation to a target for this portion of the population (215 million). Previously the indicator tracked total adult abundance (males and females) in relation to an interim target for that population (200 million).
National Oceanic and Atmospheric Administration (NOAA)
NOAA Chesapeake Bay Office