Excluder devices

These can consist of a grid of metal bars or mesh placed usually within the neck of a trawl that has an opening for escape at either the top or bottom. Examples include “skylights” which consist of a mesh opening located at the top of the codend. ”Skylights” can be combined with guiding funnels that create visual and tactile stimuli to direct finfish towards the “skylight” escape sections. A different but similar type of design is the fisheye (including Gulf and yarrow fisheyes and bigeyes) which are openings typically forming a rigid frame constructed of aluminum or steel rods and placed along the top center portion of the codend (i.e. Catchpole and Revill 2007). Typically, large animals that strike the bar exit through the opening, while the smaller target species pass through the bars and are captured in the net or codend. Examples of excluder devices in trawls are the Nordmore grid, the Turtle Excluder Device (TED), and the Sea Lion Excluder Device (SLED). A sea turtle excluder chain mat is used in the Northwest Atlantic scallop dredge fishery. A new modification to pound nets may reduce sea turtle bycatch by replacing the upper two-thirds of the leader netting with vertical ropes spaced wide enough apart to let sea turtles swim through without becoming entangled (DeAlteris et al., 2005).

Displaying 1 - 10 of 41

Study Type: 

Field study in the wild

Location: 

Spencer Gulf

Target catch: 

King prawn

Effect on bycatch species: 

Reduced capture of giant cuttlefish and blue swimmer crabs by 30-50%

Effect on target catch: 

Catch of target species was not affected

Article: 

Bycatch species: 

Reduction technique: 

Fishing Gear: 

Study Type: 

Field study in the wild

Location: 

Spencer Gulf

Target catch: 

Prawn

Effect on bycatch species: 

Small and large grids reduced number and weight of cuttlefish and crabs

Effect on target catch: 

Small grid caught less prawns compared to large grid and control nets

Article: 

Bycatch species: 

Reduction technique: 

Fishing Gear: 

Study Type: 

Field study in the wild

Location: 

Kuwait

Target catch: 

Shrimp

Effect on bycatch species: 

TED use resulted in no interactions with sea turtles or large animals; did not significantly reduce bycatch catches

Effect on target catch: 

Did not significantly reduce shrimp catches

Article: 

Bycatch species: 

Reduction technique: 

Fishing Gear: 

Study Type: 

Field study in the wild

Location: 

Swedish coast

Target catch: 

Cod

Effect on bycatch species: 

Reduced sea bycatch to zero

Effect on target catch: 

Oval shaped SEDs and ones with larger rectangle opening increased catchability of pots

Article: 

Bycatch species: 

Reduction technique: 

Fishing Gear: 

Study Type: 

Field study in the wild

Location: 

Tyrrhenian Sea

Target catch: 

Norway lobster (Nephrops norvegicus) and greater forkbeard (Phycis blennoides)

Effect on bycatch species: 

90 mm excluder grid did not reduce catches of blackmouth catshark (Galeus melastomus)

Effect on target catch: 

90 mm excluder grid reduced catches of greater forkbeard and to a lesser extend Norway lobster

Article: 

Bycatch species: 

Reduction technique: 

Fishing Gear: 

Study Type: 

Field study in the wild

Location: 

Massachusettes Bay

Target catch: 

Silver hake

Effect on bycatch species: 

There were no observed differences in the behavior of spiny dogfish between gear configurations or grate colors.

Effect on target catch: 

Article: 

Bycatch species: 

Reduction technique: 

Fishing Gear: 

Pages