The Effects of Derelict Blue Crab Traps on Marine Organisms in the Lower York River, Virginia

Derelict (abandoned or lost) traps targeting blue crab Callinectes sapidus have the potential to affect the blue crab fishery and other marine-oriented species. We used side-scan sonar to locate derelict traps and assess their extent and accumulation rate. Experimental traps were monitored at four locations to calculate catch rates of marine organisms and trap degradation rates. In 2006, 635-676 derelict traps were identified in a 33.5-km(2) area of the lower York River in Virginia's portion of the Chesapeake Bay. Trap loss rates are estimated at 30%, resulting in the potential addition of over 100,000 traps annually to the Chesapeake Bay derelict trap population in Virginia. The top four species captured in the experimental traps were blue crab, Atlantic croaker Micro-pogonias undulates, oyster toadfish Opsanus ton, and white perch Morone americana. Experimental derelict traps captured 50.6 blue crabs.trap(-1).season(-1) during April-November 2006 and 13.6 Atlantic croakers.trap(-1).season(-1) during May August 2006. There was no difference in catch rates between traps of different ages. Baiting traps to simulate entrapped fish (self-baiting) doubled the catch rate. Experimental derelict traps continued to capture organisms for at least I year, which suggests that derelict traps could affect blue crab populations.