Reducing negative ecological impacts of capture fisheries through gear modification

Capture fisheries provide the world with a healthy source of protein than can have minimal environmental impacts if harvested sustainably. Negative environmental impacts of capture fisheries include; overexploitation, modification of food webs, mortality of nontarget species, habitat alteration and biodiversity loss. A mitigation technique often used to reduce ecological impacts of fishing without compromising commercial catches is gear modification. This thesis explores modification of two gear types; shrimp trawl and turbot longline. Modifications were made to shrimp trawl footgear to reduce habitat alteration and to turbot longline gear to reduce Greenland shark bycatch. Testing of modified with traditional gears demonstrated that the modified gears with reduced ecological impacts did not negatively affect commercial catches. The 200 lb monofilament gangion is recommended for commercial testing by turbot longline fishers in Cumberland Sound; however the aligned shrimp trawl requires further modifications due to unexpected increases in turbot bycatch compared to the traditional trawl