Summary: | <p><a target=\"blank\" href=\"http://nec.whoi.edu/pdf/DOGGRATE_final_report.pdf\">See final report</a></p> <p>A spiny dogfish <i>Squalus acanthias</i> excluder grate (grid) within the extension of a silver hake (whiting) <i>Merluccius bilinearis</i> trawl net was designed and tested in Massachusetts Bay. We collected evidence between October 2008 and August 2009 using live-fed underwater video footage around the grate to support the proof of concept. Grates with 50 mm (2 in) spacing were investigated for effects from color (white or black), angles of placement, and direction (leading to a top or bottom escape vent). Spiny dogfish numbers were greatly reduced for all gear configurations based on video observations and data collected from the codend. Catches of target species were sizeable. Four tows (of various gear configurations) resulted in spiny dogfish blockages in front of the grate. The reduction of spiny dogfish led to apparent increases in the quality of marketable catches, reductions in non-target species mortality, and decreases in the codend catch handling times.</p> <p>Study location: northwest of Cape Cod</p>
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