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Tests with captive, as well as wild, juvenile sandbar sharks (Carcharhinus plumbeus) were undertaken to determine the effectiveness of electropositive metals in reducing the interactions with longline gear.  Electropositive metals deterred feeding in groups of captive juvenile sharks for a short period of time and altered the swimming patterns of individuals when food motivation was not present.  In the field, electropositive metals placed within 10 cm of the bottom longline hooks reduced the catch of sandbar sharks by around two thirds, compared to the catch on hooks with a placebo.

The catches from five experimental trawls (TED + fisheye BRD, upward facing TED, downward facing TED, bigeye BRD and square-mesh panel BRD) were compared to those of the standard twin Florida Flyer prawn trawl. Nets with a combination of a TED and BRD reduced sea turtle catches by 100%, large sponges by 85.3%, sharks by 36.3% and rays by 17.7% and reduced the proportion of soft and damaged prawns by 41.6% and catches of tiger prawns by 6.5%. Upward and downward facing TEDs reduced sea turtle bycatch by 99% and 100% respectively and large sponges by 81.6% and 95.9% respectively. Catches of tiger prawns (P. semisulcatus and P. esculentus) were reduced by 6.3% with the use of TEDs. The BRDs had little impact on the catch of either target or bycatch species.

This study evaluated the impacts of hook size on catch of discards of reef in the bottom longline fishery in the eastern Gulf of Mexico. Larger 15/0 hooks successfully reduced primary target species (red grouper, Epinephelus morio) discards by 38% in comparison to 13/0 hooks, but decreased catch of other important species, including red snapper (Lutjanus campechanus). 15/0 hooks also significantly reduced catch rates of Atlantic sharpnose shark (Rhizoprionodon terraenovae) and spiny dogfish (Squalus acanthias).