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A survey was conducted with fishers in Galicia Spain to investigate interactions between fishing gear and cetaceans. Cetacean fishery interactions appear to be frequent events. Although the damage to the catch and fishing gear were generally reported to be small, substantial economic loss can result from interactions with common bottlenose dolphin (Tursiops truncatus) and coastal gillnet fishing gear, and from short-beaked common dolphins (Delphinus delphis) interactions with purse seine fisheries. Bycatch mortality for cetaceans was reported to be highest in trawl and set gillnet fisheries.

Three types of bycatch reduction devices (BRD) [turtle excluder device (TED), square mesh codend (SMC) and fisheye (FE)] were tested aboard shrimp trawl vessels. Differences in catch from nets equipped with a BRD on one side and a standard net on the other were compared for each of the three BRD's. Use of the TED resulted in no captures of sea turtles or large animals, and did not significantly reduce shrimp catches or fish bycatch. The SMC reduced both shrimp and bycatch catches, although only a reduction in bycatch was significant.The SMC did result in catches of larger shrimp compared to the other nets. The FE significantly reduced shrimp and bycatch catches.

Three types of bycatch reduction devices (BRD) [turtle excluder device (TED), square mesh codend (SMC) and fisheye (FE)] were tested aboard shrimp trawl vessels. Differences in catch from nets equipped with a BRD on one side and a standard net on the other were compared for each of the three BRD's. Use of the TED resulted in no captures of sea turtles or large animals, and did not significantly reduce shrimp catches or fish bycatch. The SMC reduced both shrimp and bycatch catches, although only a reduction in bycatch was significant.The SMC did result in catches of larger shrimp compared to the other nets. The FE significantly reduced shrimp and bycatch catches.

Three types of bycatch reduction devices (BRD) [turtle excluder device (TED), square mesh codend (SMC) and fisheye (FE)] were tested aboard shrimp trawl vessels. Differences in catch from nets equipped with a BRD on one side and a standard net on the other were compared for each of the three BRD's. Use of the TED resulted in no captures of sea turtles or large animals, and did not significantly reduce shrimp catches or fish bycatch. The SMC reduced both shrimp and bycatch catches, although only a reduction in bycatch was significant.The SMC did result in catches of larger shrimp compared to the other nets. The FE significantly reduced shrimp and bycatch catches.

A study was conducted aboard vessels from the South Australian Spencer Gulf prawn fishery to examine the utility of a mechanical-separating bycatch reduction device. The fishery targets prawns but has bycatch of giant cuttlefish (Sepia apama) and blue swimmer crabs (Portunus armatus). Conventional codends were tested against small and large Nordmore-grids set at high and low grid angles. Both grids resulted in bycatch reductions. The number and weight of cuttlefish were reduced by 50.4% and 59.7%, respectively, when the small grid was used. The large grid resulted in a reduction of 33.5% in number and 36.6% in weight of cuttlefish. Crab bycatch was reduced by 40.2% (number) and 47.5% (weight) when the small grid was used, and 40.9% (number) and 38.1% (weight) when the large grid was used. A reduction in prawn catch (weight) was observed when the small grid was used compared with the large and control grid.

The behavior of inshore squid (Dorytheuthis pealeii) in response to a Nordmore-style finfish bycatch reduction grid was evaluated n Nantucket Sound off Cape Cod Massachusetts. Squid avoided the grid and escape by jetting and changing directions. Only 6.4% of the squid became stuck on the grid and 83.9% of these were able to eventually pass between the grid and its spacing into the codend. Squid approaching the grid from the top with their mantel oriented toward the grid were more likely to be caught.

Tests were conducted aboard a mid-water trawler fishing for hake in the Pacific Ocean off the Oregon coast (US) to determine if and how artificial illumination could be used to aid in the escapement of Chinook salmon (Oncorhynchus tshawytscha) out an escape window. The study looked at not only the ability of artificial illumination to aid in escapement but also if it could be used to influence which escape window was used. The lights used were LED lights, and data was collected with a video camera. Two square-mesh ramps were built around a four-seam tube of netting (135 meshes deep and 136 meshes circumference) and inserted between the intermediate section of the trawl and the tube forward of the codend. This device was used to guide fish towards two escape windows cut out of each side of the tupe (upper portion of both port and starboard side). DeepSea Power and Light LED Multi-SeaLites Matrix lights were randomly placed (one each) at each escape window. The light was placed inside the trawl and pointed outward. Chinook moved towards and out specific escape windows when artificial illumination was used, suggesting artificial illumination could be used to help Chinook escape. There was a 32.4% reduction in rockfish bycatch. Pacific hake behavior was noted. Hake drifted towards the codend during the tow process.

A flexible sorting grid was tested in the US west coast groundfish trawl fishery for its ability to reduce the bycatch of rockfish, sablefish and Pacific halibut without reducing catches of targeted flatfish. The grid works by allowing fish smaller than it to enter the codend, while fish larger than the grid openings are able to escape. The flexible sorting grid used four-seam tube of netting 80 meshes deep and 100 meshes in circumference. It was inserted between the intermediate section of the bottom trawl and codend. Two vertical panels were used to direct fish towards an upward ramp. A recapture net was used to quantify retention and escapements. Retention of flatfish species ranged from 74.8-93.3%. Retention was highest for Petrale sole (93.3%), Dover sole (89.4%) and English sole (87.9%). Rockfish that were 36 cm or larger had the largest escapement rate of 94.6%. For lingcod and sablefish, 92% of fish 38 cm or larger escaped. For targeted flatfish, 85.1% that were encountered were retained. For bycatch species, 72.1% of rockfish, 96.5% of roundfishes and 93.7% of Pacific halibut that were encountered were able to escape.

A flexible sorting grid designed by industry was tested in the US west coast groundfish trawl fishery for its ability to reduce bycatch. The flexible sorting grid was made within a four-seam tube of netting, 50 meshes deep and 88 meshes in circumference. The grid was inserted between the intermediate section of the bottom trawl and the codend. A horizontal sorting panel crowds fish and directs them through an escape opening in the bottom of the trawl. A recapture net was used to quantify retention and escapement. Bycatch of Pacific halibut was reduced by 83.7% and 74.3% by weight and numbers, respectively. Pacific halibut larger than 80 cm had the highest escapement rates. Retention rates for target species were 93.3 % (arrowtooth flounder), 99% (Dover sole) amd 96.9% (petrale sole). Sablefish retention was 90% and shortspin thronyhead retention was 96.9%. Sablefish over 79 cm in size represented 50% of the total loss of target species. 

A mechanical separating bycatch reduction device was tested in the Spencer Gulf king prawn trawl fishery to reduce the incidental capture of giant cuttlefish (Sepia apama) and blue swimmer crabs (Portunus armatus). Different sizes of Nordmore grids were tested. Two Nordmore grids were inserted into the posterior extension sections and triangular escape exits were cut out. One grid was located in the extension with an angle of -45 degrees (small grid) and the second large grid was set at a 30 degree angle in the extension. The large Nordmore grid significantly reduced bycatch of cuttlefish and blue swimmer crabs by 30-50%. Catches of king prawn were not impacted by the use of Nordmore grids.