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A new otterboard door design (Clarck-Y door) was tested in both flume tanks and at sea to compare its possible impact on the seabed compared to an existing door (Cambered vee) design. The two doors had a similar behavior with regard to the attack angle and the magnitude of drag, lift and efficiency coefficients in the flume tank experiment. In the sea trials, the Cambered vee door had higher values for the drag and lift coefficients than the Clarck-Y door and the horizontal door spread was also higher in the Cambered vee compared to the Clarck-Y door.

In northern hemisphere trawl fisheries, little is known about the extent of cable strike seabird mortality or techniques to mitigate it. We compared the rate of heavy seabird strikes by third-wire cables and warps, using three mitigation measures compared to a control of no mitigation. Experiments were conducted aboard two catcher-processor vessels targeting walleye pollock (Theragra chalcogramma) in the eastern Bering Sea: one that rendered offal into fish meal and fish oil (Vessel R) and one that minced offal prior to discharge (Vessel M).