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Acoustic Harassment Devices were not found to be effective in deterring New Zealand fur seals (Arctocephalus forsteri) from mid-water trawls in the New Zealand hoki (Macruronus novaezelandiae) fishery. Sea Lion Escape Devices are undergoing testing in New Zealand˙s hoki trawl fishery (for fur seals) and the squid trawl fishery (for Hookers (New Zealand)  sea lion (Phocarctos hookeri)). Preliminary results indicate squid and fish loss via the escape hatch was minimal; in the hoki fishery, fish loss was confined to fast swimming species, including jack mackerel and warehou.

Acoustic Harassment Devices were not found to be effective in deterring New Zealand fur seals (Arctocephalus forsteri) from mid-water trawls in the New Zealand hoki (Macruronus novaezelandiae) fishery. Sea Lion Escape Devices are undergoing testing in New Zealand˙s hoki trawl fishery (for fur seals) and the squid trawl fishery (for Hookers (New Zealand)  sea lion (Phocarctos hookeri)). Preliminary results indicate squid and fish loss via the escape hatch was minimal; in the hoki fishery, fish loss was confined to fast swimming species, including jack mackerel and warehou.

Circle hooks significantly reduce loggerhead (Caretta caretta) and leatherback (Dermocheles coriacea) sea turtle bycatch in Atlantic longline fisheries. Swordfish (Xiphias gladius) catch decreased when circle hooks were baited with squid but increased when baited with mackerel. Tuna catch increased when circle hooks were baited with squid but decreased when baited with mackerel.

Circle hooks (non-offset 16/0 and 18/0) did not significantly reduce the number of loggerhead sea turtles (Caretta caretta) caught in the Azores (Portugal) longline swordfish (Xiphias gladius) and blue shark (Prionace glauca) fishery when compared with non-offset and offset 9/0 J hooks. Use of circle hooks decreased the rate of throat hooking in loggerhead sea turtles (Caretta caretta). Circle hooks (non-offset 16/0 and 18/0) caught significantly more blue sharks than J hooks in the Azores longline swordfish and blue shark fisheries. 

There was no significant difference in the number of loggerhead sea turtles (Caretta caretta) caught in the Azores (Portugal) longline swordfish (Xiphias gladius) and blue shark (Prionace glauca) fishery between straight 16/0, offset 16/0, and offset 18/0 circle hooks. Circle hooks decreased the rate of throat hooking in loggerhead sea turtles (Caretta caretta) caught in the Azores longline swordfish and blue shark fishery. Straight 16/0 circle hooks caught the most blue sharks in the Azores longline swordfish and blue shark fishery, followed by offset 18/0 circle hooks. Offset 16/0 circle hooks caught the fewest blue sharks.

A Japanese tuna hook 3.6mm S/S caught significantly more loggerhead sea turtles (Caretta caretta) than non-offset 16/0 and 18/0 circle hooks and caught more turtles in the throat than the circle hooks in the Azores (Portugal) longline swordfish (Xiphias gladius) and blue shark (Prionace glauca) fishery. Non-offset 18/0 circle hooks caught fewer loggerhead sea turtles (Caretta caretta) than non-offset 16/0 circle hooks in the Azores longline swordfish and blue shark fishery. There was no significant difference in the number of blue sharks caught on non-offset 16/0 and 18/0 circle hooks in the Azores longline swordfish and blue shark fishery.

Circle hooks (non-offset 16/0 and 18/0) caught significantly more target blue sharks (Prionace glauca) than J hooks in the Azores (Portugal) longline swordfish (Xiphias gladius) fishery. There was no significant difference among the hook types tested in the number of loggerhead sea turtles (Caretta caretta) caught, although J hooks had a significantly higher rate of throat capture compared with circle hooks. 

Blue-dyed bait does not significantly reduce loggerhead (Caretta caretta) and leatherback (Dermocheles coriacea) sea turtle captures in the western Atlantic longline fishery.

Metal oxide nets containing barium sulphate (that increased their acoustic reflectivity and probably also their stiffness) reduced the bycatch of harbor porpoise (Phocoena phocoena) in an eastern Canada demersal gillnet fishery. No difference in catch of commercial fish species, including cod (Gadus morhua), pollock (Pollachius virens), haddock (Melanogrammus aeglefinus), and spiny dogfish (Squalus acanthias), was observed between the nylon and barium sulphate nets. Metal oxide nets reduced the bycatch of greater shearwater (Puffinus gravis) in an eastern Canada demersal gillnet fishery, probably by increasing the visibility of the blue-dyed nets to the birds.