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Gillnets with three difference mesh sizes (2 7/8", 3" and 4") were modified to use 200 lbs/200 yard lead line and 11 oz buoyancy floats (versus 50lbs/200 yard lead line and 3 oz floats) to increase the tension in the net. Catch rates of Atlantic sharpnose and bonnethead sharks were significantly lower in the 4" modified net. The proportion of hammer-wrapped bonnethead sharks was significantly higher in the 4" unmodified net and significantly less blacktip sharks were wrapped in the 3" modified net. Selectivity of blacknose sharks varied between the modified and unmodified nets. Catch rates of targeted Spanish mackerel and spot were not significantly different between modified and unmodified nets.

The addition of a filter grid (inclined at ca. 20 degrees) that leads to an escape tunnel in trawl nets allowed 100% of rays and turtles to escape, 75% of manta rays, 40% of billfish and between 20-75% of sharks to escape.

The addition of a filter grid (inclined at ca. 20 degrees) that leads to an escape tunnel in trawl nets allowed 100% of rays and turtles to escape, 75% of manta rays, 40% of billfish and between 20-75% of sharks to escape.

The addition of a filter grid (inclined at ca. 20 degrees) that leads to an escape tunnel in trawl nets allowed 100% of rays and turtles to escape, 75% of manta rays, 40% of billfish and between 20-75% of sharks to escape.

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 TED's reduced sea turtle bycatch by 99% and 100% respectively and large sponges by 81.6% and 95.9% respectively. Catches of tiger prawns were reduced by 6.3% with the use of TED's. The BRD's had little impact on the catch of either the target or bycatch species.

Two types of streamer lines, a "light" with short streamers and a "hybrid" with mixed long and short streamers, were tested in the Japanese joint venture tuna fishery that operates in the South African EEZ.  The authors also looked at differences in catch rates between weighted and unweighted branchlines. The mean total attack rate was similar for each design but diving birds attacked further astern in response to both tori line types compared to surface foraging birds.  The "hybrid" line did not allow attacks by divers within 50 m but the "light" line allowed attacks through out all distances astern monitored. Surface foragers did not attack within 0-25 m of the "hybrid" line or at distances greater than 100 m of the "light" line.  Catch rates of birds were higher on unweighted compared to weighted branchlines.  Catch rates of fish were not significantly different between the two branchline types at night or during the dawn.

Two types of streamer lines, a "light" with short streamers and a "hybrid" with mixed long and short streamers, were tested in the Japanese joint venture tuna fishery that operates in the South African EEZ.  The authors also looked at differences in catch rates between weighted and unweighted branchlines. The mean total attack rate was similar for each design but diving birds attacked further astern in response to both tori line types compared to surface foraging birds.  The "hybrid" line did not allow attacks by divers within 50 m but the "light" line allowed attacks through out all distances astern monitored. Surface foragers did not attack within 0-25 m of the "hybrid" line or at distances greater than 100 m of the "light" line.  Catch rates of birds were higher on unweighted compared to weighted branchlines.  Catch rates of fish were not significantly different between the two branchline types at night or during the dawn.

The effectiveness of 18/0 circle hooks, compared to 9/0 J-type hooks, in decreasing the incidental capture and post-release mortaliity of sea turtles was tested in the Brazilian pelagic longline fishery operating in the south-western Atlantic Ocean.  The incidental capture of loggerhead sea turtles was reduced by 55% and for leatherback sea turtles by 65% when circle hooks were used.  De-hooking also decreased from 25% to 5.8% in loggerhead sea turtles when circle hooks were used, likely increasing their post-release survival rates.  Catch rates of targeted species including bigeye and albacore tuna and blue sharks increased with the use of circle hooks, while no difference in catch rates between hook types was found for yellowfin tuna, shortfin mako or hammerhead sharks or for dolphinfish.  However, swordfish, another target species, catch rates were significantly reduced with the use of circle hooks.

Four types of hooks, J-style, tuna hook, tuna 18 offset and circle hooks were tested on pelagic loglines fishing close to Mazatlan Mexico to determine their effectiveness at catching sharks and other pelagic species.  Circle hooks had the highest catch rates for the principal target species, blue and striped marlin.