Mobile Gear Case Study:
Transcription
Mobile Gear Case Study:
Mobile Gear Case Study: Effectiveness of Trawl Modifications to Reduce Atlantic Cod By-Catch in U.S. Haddock Fishery on Georges Bank Paul Winger Centre for Sustainable Aquatic Resources Marine Institute, Memorial University of Newfoundland St. John’s, Newfoundland, Canada www.mi.mun.ca/csar Many finfish exhibit species-specific behaviour while swimming and exhausting in the mouth of a bottom trawl. Several studies are now underway to improve trawl selectivity for haddock, cod, pollack, and various flatfish species by taking advantage of these behaviour patterns. (Main and Sangster, 1981) Design and Test of a High Opening Raised Footrope Trawl for Haddock and Pollack for the inshore Gulf of Maine Pingguo He, UNH Vincent Balzano Tim Eddy Purpose: To design and test a new trawl employing both a high headline opening for haddock/pollack as well as a raised footrope with long drop chains for escapement of cod and bottom dwelling species. Results: Twelve experimental rigs were tested in the CSAR flume tank. Initial sea trials in 2005 were encouraging. Next Steps: Additional sea trials scheduled for summer 2006. 5’ drop chains Rope Separator Trawl for Haddock and Pollack using “B” Days-at-sea in the Inshore Western Gulf of Maine Pingguo He, UNH Carl Bouchard Purpose: To design and test a specialized rope separator trawl that uses a series of parallel ropes instead of netting to reduce the problem of fish meshing in traditional separator panels, especially dogfish. Results: Flume tank tested at CSAR in December 2004. Initial sea trials in 2005 were encouraging. Next Steps: Additional sea trials scheduled for summer 2006. F/V Stormy Weather Using a 4-Seam Bottom Trawl to Improve Escapement of Small Haddock and Cod Dana Morse, UMaine Kelo Pinkham Claudia Coffin Purpose: To examine the use of square mesh side panels inserted into a 2-seam trawl as well as an increased taper in the trawl belly, on reducing catches of juvenile groundfish in the Gulf of Maine. F/V Bad Penney F/V Ocean Reporter Results: Field trials showed a reduction in the catches of undersized cod and haddock. Some larger marketsized individuals were also lost. Other fish species appear unaffected. Further work will continue to refine this promising approach. Next Steps: Field trials in summer of 2006 will test 6” hexagonal mesh in the side panels Testing a Modified Squid Net to Target Haddock in the Gulf of Maine. Purpose: To modify a commercial squid net to target haddock while at the same time reducing the incidental capture of cod and bottom dwelling species. David Beutel, URI Laura Skrobe, URI Jonathan Knight Phil O’Grady Jim Ruhle Approach: Installed large 8-foot mesh in the bottom belly to facilitate downward escapement of cod and flatfish. Installed kites to increase headline height. Results: 3 trips have shown positive results. Next Steps: Additional sea trials planned for 2006. Content for this presentation was kindly contributed by: Pingguo He Dana Morse Mike Pol David Beutel UNH University of Maine Mass. DMF URI Thank You Dr. Paul Winger Director Centre for Sustainable Aquatic Resources