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Tests were conducted aboard pelagic longline vessels fishing off the coast of Uruguay, to determine the effect of hook type (circle hook vs J-hook) on the catch and length composition of target and non-target species.  Both American and Spanish style longlines were used during these experiments.  American style longlines consist of a 3.6 mm polyamide monofilament mainline with polyamide or polyester buoys lines 9-36 m long.  Spanish style longlines consist of 5-mm polyethlene multifilament mainline with buoy lines (similar in thickness and material to mainline) 12-18 m long.

Modified trap openings were developed to reduce juvenile rockfish bycatch in British Columbia spot prawn traps. Smaller trap openings had no impact on rockfish or other non-target species bycatch. A novel bent tunnel opening resulted in no rockfish bycatch and the exclusion of other fish species. However, all trap modifications resulted in reductions in prawn catch rates. Large prawns were also excluded more than small prawns.  

Two types of depredation mitigation devices (DMD) were designed and tested aboard pelagic longline fishing vessels targeting tunas and swordfish off the Seychelles.  The DMD's were designed to reduce the damage and removal of fish from the fishing gear by predators such as toothed whales and sharks. The first DMD was termed "spider" and was made up of a 100 mm diameter plastic disc with sixteen holes in its outer range and a 37 mm diameter central hole.

Fisheries observers and skippers tested the effectiveness of the Dolphin Dissuasive Device (DDD) as a bycatch mitigation tool for porpoises and dolphins. This study was conducted aboard fishing vessels in the Cornish over-12m static net sector fishery in the waters of Southwest England. DDD's were placed at the end nets. The DDD's caught significantly fewer porpoises but no significant difference in dolphin bycatch was observed.