Importance of Blue Crab Life History for Stock Enhancement and Spatial Management of the Fishery in Chesapeake Bay

Abstract

Due to over-harvesting and habitat degradation, spawning stock abundance and biomass of the Chesapeake Bay blue crab (Callinectes sapidus) has declined over 80% in the last 15 years. In addition, only a small portion (11–22%) of the spawning stock migrates successfully to the historic spawning areas of the lower estuary. As a result, recent management goals to decrease harvests and increase spawning stock biomass have been adopted by the different Chesapeake Bay regulatory agencies. The crisis has also prompted an experimental assessment of the potential for stock enhancement to increase the number of spawners. While much of the current stock enhancement work has focused on assessing the competency of hatchery-reared individuals and identifying key processes that optimize survival and growth of juveniles to maturity, less attention has been paid to examining factors that influence the long-term efficacy of stock enhancement efforts. Here we discuss important interactions between blue crab life history, stock enhancement efforts, and management options available to increase the standing stock of mature females in Chesapeake Bay. We propose the establishment of migration corridors to protect female blue crabs when they undergo the long-distance migration after mating to lower Bay spawning areas.

Keywords:

• Callinectes sapidus
• marine sanctuary
• corridor
• migration
• overharvest
• restocking

ACKNOWLEDGEMENTS

This work was aided by the assistance of numerous Smithsonian Environmental Research Center staff, interns, volunteers, and graduate students, including, but not limited to Alicia Young, Jana Davis, Heather Turner, Ben Daly, Erin Kelly, Kathryn Chop, Emily Gamelin, Kim Tengardjaja, James Wolf, Anna Miller, and Paula Rodgers. We also thank commercial and recreational crabbers for reporting marked blue crabs and cooperating with our research. Anonymous reviewers provided extensive comments in the final preparation of this manuscript. We acknowledge the assistance of Dr. Yonathan Zohar, University of Maryland, Biotechnology Institute, Center of Marine Biotechnology (COMB). This research was supported by funds from NOAA Chesapeake Bay Program Office to the Blue Crab Advanced Research Consortium (BCARC), Maryland Sea Grant College Program, and Smithsonian Environmental Science Program.

Notes

^A Commercial fishers must take either Sunday or Monday off.

^B All commercial crabbing is prohibited on Sundays, except fishing peeler pots and tending other gear (shedding facilities, floats, nets, etc.). In addition, dredging is prohibited on Saturdays.