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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 and 10.5% more endeavour 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.

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 and 10.5% more endeavour 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.

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 and 10.5% more endeavour 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.

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 and 10.5% more endeavour 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.

Experiments using squid dyed with Brilliant Blue dye were undertaken aboard tuna longline vessels off East Cape, New Zealand, to determine the dyed baits ability to reduce the incidental capture of seabirds.  Significant differences in catch rates between bait types were observed when all species were combined and for seabird mortality, but the authors identified problems with the statistical design, which make the results not very convincing and therefore inconclusive.  In addition, at sea observations of seabird behavior during the deployment of the longline gear, suggest the dye did not effectively camouflage the bait.  Instead the authors suggest seabirds may reject the blue dyed bait due to its color after either seeing it or investigating it through pecking and/or eating.

Tests were conducted aboard Canadian longline vessels targeting swordfish to determine if there were differences in the catch rates and size composition of swordfish and bycatch species caught by monofilament and multifilament nylon gangions.  No significant differences in the mean lengths of swordfish were found between the two nylon gangions but catch rates did differ significantly, with more swordfish caught on the monofilament gangions.  There was also a significant difference in catch rates between the two gangions for blue sharks and pelagic stingrays, with more animals caught on monofilament gangions.  There was no significant difference in catch rates between gangions for mako sharks, white marlin or loggerhead sea turtles.

Tests were conducted aboard Canadian longline vessels targeting swordfish to determine if there were differences in the catch rates and size composition of swordfish and bycatch species caught by monofilament and multifilament nylon gangions.  No significant differences in the mean lengths of swordfish were found between the two nylon gangions but catch rates did differ significantly, with more swordfish caught on the monofilament gangions.  There was also a significant difference in catch rates between the two gangions for blue sharks and pelagic stingrays, with more animals caught on monofilament gangions.  There was no significant difference in catch rates between gangions for mako sharks, white marlin or loggerhead sea turtles.

Tests were conducted aboard Canadian longline vessels targeting swordfish to determine if there were differences in the catch rates and size composition of swordfish and bycatch species caught by monofilament and multifilament nylon gangions.  No significant differences in the mean lengths of swordfish were found between the two nylon gangions but catch rates did differ significantly, with more swordfish caught on the monofilament gangions.  There was also a significant difference in catch rates between the two gangions for blue sharks and pelagic stingrays, with more animals caught on monofilament gangions.  There was no significant difference in catch rates between gangions for mako sharks, white marlin or loggerhead sea turtles.

The use of blue-dyed squid bait on pelagic longlines was tested to determine its ability to reduce both surface and subsurface interactions with seabirds.  In addition, blue-dyed fish bait was tested for its ability to reduce seabird strikes at the surface. Blue-dyed squid bait reduced seabird interactions by 68% compared to non-dyed squid bait when the longline was submerged, and only 3-8% of the blue-dyed squid bait were struck at the surface, compared to 75-98% of non-dyed squid bait.  Around 48% of blue-dyed fish bait was struck at the surface during the first two days of the trial, and 90% were struck over the last three days of the trial.

Tests were conducted aboard pelagic longline vessels in the Bay of Bengal to determine if there were differences in the catch composition, catch rate, hooking position or length frequency of target and bycatch species caught with circle and J-hooks.  Circle hooks caught similar percentages of both target (46.7%) and bycatch (53.3%) species, while J-hooks caught a higher percentage of bycatch (74.5%) species.  Catch rates for the target species were higher for circle hooks (2.2 individuals/1,000 hooks) compared to J-hooks (1.9 individuals/1,000 hooks).  In contrast, catch rates for the bycatch species were higher on J-hooks (5.6 individuals/1,000 hooks) than circle hooks (2.6 individuals/1,000 hooks).  For the target species, swordfish had the higest catch rates for both hook types but catch rates were slightly higher on circle hooks.  Close to three quarters (73.3%) of fish were hooked in the mouth when circle hooks were used while only half (53%) were hooked in the mouth, and 38% in the digestive system, when J-hooks were used.  Swordfish caught with J-hooks were slightly larger (mode of 250-269 cm) than those caught with circle hooks (mode 210-229 cm).