Physical Sciences and Mathematics Commons^™

Seabed Classification For Trawlability Determined With A Multibeam Echo Sounder On Snakehead Bank In The Gulf Of Alaska, Thomas C. Weber, Chris Rooper, John L. Butler, Darin Jones, Chris Wilson

Center for Coastal and Ocean Mapping

—Rockfishes (Sebastes spp.) tend to aggregate near rocky, cobble, or generally rugged areas that are difficult to survey with bottom trawls, and evidence indicates that assemblages of rockfish species may differ between areas accessible to trawling and those areas that are not. Consequently, it is important to determine grounds that are trawlable or untrawlable so that the areas where trawl survey results should be applied are accurately identified. To this end, we used multibeam echosounder data to generate metrics that describe the seafloor: backscatter strength at normal and oblique incidence angles, the variation of the angle-dependent backscatter strength within 10° …