P-107
Confirming Video Survey Sediment and Juvenile Sea Scallop Observations Using a Modified Sled Dredge

Monday, August 18, 2014
Exhibit Hall 400AB (Centre des congrès de Québec // Québec City Convention Centre)
Richard Malloy Jr. , Fisheries Oceanography, University of Massachusetts Dartmouth SMAST, Fairhaven, MA
Kevin D.E. Stokesbury , School for Marine Science and Technology (SMAST), University of Massachusetts Dartmouth, Fairhaven, MA
N.David Bethoney , School of Marine Science and Technology, University of Massachusetts Dartmouth, Fairhaven, MA
Susan Inglis , Department of Fisheries Oceanography, SMAST, University of Massachusetts, Dartmouth, New Bedford, MA
The U.S. Atlantic sea scallop (Placopecten magellanicus) resource has been video surveying for over a decade. These data have been used in many different ways, including the creation of sediment maps and as an input into the scallop stock assessment. However, a consistent criticism of the video survey is the lack of physical samples. Physical samples taken in conjunction with the video survey could confirm sediment classifications and juvenile scallop detection. To address these specific issues, we modified a New Bedford style dredge by reducing the ring size, and adding sediment traps, lights and cameras. During a proof of concept trip on Georges Bank, we deployed the modified dredge and the video survey pyramid, successfully collecting sediment samples at eight different sites. Video footage of small scallops evading the dredge and low catch of scallops <40 mm shell height; suggest that the high resolution images taken by the video survey better quantify the amount of small scallops on the sea floor. Future work will include the addition of a liner to enhance the dredge's ability to capture small scallops and analysis of dredge catchability and sediment classification.