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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 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.

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 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.