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Summary: Low profile gillnets with a panel height of six feet and no tie downs or additional floats had significantly fewer interactions with sea turtles and caught significantly less bycatch than standard gillnets. Catches of the target species (flounder) were also reduced in the low profile gillnets.

Summary:

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.

Summary: A semi-flexible exclusion grid with a bar spacing of 15.5 cm reduced dolphin bycatch in the Pilbara trawl fishery by close to 50% and reduced the bycatch of sea turtles, large sharks and rays. However, the fate of the dolphins that encountered the grid and escaped is unknown.

Summary:

The addition of a prototype "tunnel excluder" consisting of a filter grid (inclined at ca. 20 degrees) that leads to an escape tunnel in the Mauritanian industrial trawl fishery nets achieved a 40-100% reduction in bycatch of vulnerable species, including allowing 100% of rays and turtles to escape, 75% of manta rays, 40% of billfish and between 20-75% of sharks to escape. Cetaceans were less likely to use the tunnel to escape due to the narrowness of the design. 

Summary:

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.

Summary:

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.

Summary:

Leaders in offshore, deep water pound nets in the Virginia portion of Chesapeake Bay (United States) incidentally take protected sea turtles. To reduce this take, federal resource managers restricted the use of traditional leaders during periods of peak sea turtle strandings. In response to these restrictions, a modified leader was developed. Testing of the new design in 2004 and 2005 indicated that the modified leader significantly reduced sea turtle interactions. Finfish were also sampled from the nets in the study, with results showing no difference in catch weights of four finfish species and the experimental leader harvesting significantly more of a fifth species than the control.

Summary:

Fishery observer data was used to estimate interactions between hard-shelled sea turtles and dredge gear in the US Mid Atlantic before and after the implementation of chain mats.  A total of 288 annual interactions between hard-shelled sea turtles and dredge gear were estimated to have occurred between 2001 and 2006, while 20 annual interactions occurred between 2006 and 2008, after chain mats were introduced into the fishery.  If chain mats had not been used during this second time period (2006-2008), it was estimated that 125 interactions would have occurred. Therefore, the introduction of chain mats reduced the rate of interactions between hard shelled sea turtles and dredge gear.

Summary:

Two new types of turtle excluder devices were tested in the Northern Australia prawn fishery to determine their ability to exclude sea turtles from capture.  The first design, JT 1, had a large escape opening across the width of the top panel ahead of the codend, with the forward edge of the escape weighted down and the aft edge buoyed.  This design did not prevent the capture of sea turtles or other large sharks and rays but caught 6.6% more tiger prawns (Peneaus sp.) and 10.5% more endeavour (Metapenaeus sp.) prawns than the standard net.  The second design, JT 2, had two large holes (200 cm long x 30 meshes deep) cut into the side panels of the net ahead of the codend with the aft edge weighted and two standard (40 mesh wide) bigeye escape panels were added between the two side openings.  The second design also did not prevent the capture of sea turtles or other large sharks and rays but did reduce finfish bycatch by 5% and caught 5.2% more tiger prawns and 6.9% more endeavour prawns compared to standard nets.

Summary:

Two new types of turtle excluder devices were tested in the Northern Australia prawn fishery to determine their ability to exclude sea turtles from capture.  The first design, JT 1, had a large escape opening across the width of the top panel ahead of the codend, with the forward edge of the escape weighted down and the aft edge buoyed.  This design did not prevent the capture of sea turtles or other large sharks and rays but caught 6.6% more tiger prawns (Peneaus sp.) and 10.5% more endeavour (Metapenaeus sp.) prawns than the standard net.  The second design, JT 2, had two large holes (200 cm long x 30 meshes deep) cut into the side panels of the net ahead of the codend with the aft edge weighted and two standard (40 mesh wide) bigeye escape panels were added between the two side openings.  The second design also did not prevent the capture of sea turtles or other large sharks and rays but did reduce finfish bycatch by 5% and caught 5.2% more tiger prawns and 6.9% more endeavour prawns compared to standard nets.