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Working with industry, two key methods have been developed in recent years to reduce bycatch in the shrimp fishery. Bycatch reduction devices or "BRD's" are circular grates which physically remove larger fish before reaching the codend and the use of LED fishing lights on the footrope encourages strong swimming fish such as smelt, rockfish and flatfish to avoid the net completely.
Developed through cooperative research between fishermen and ODFW biologists, Bycatch Reduction Devices (BRD's)are aluminum grids that guide large fish out of the net through an open hole in the trawl while keeping the shrimp in the net. Oregon's shrimp industry led the mandatory implementation of these devices for their fishery and they have greatly reduced bycatch in Oregon's pink shrimp fishery. The use of this device has not only made sorting of fish from the shrimp catch easier, but has allowed shrimp boats to work in areas previously unfishable due to bycatch levels. By nearly eliminating the bycatch of larger fish such as halibut, canary, and yelloweye rockfish, BRD's have also contributed to the minimization of fishery impacts to these species. The set up (as seen below) is similar to turtle excluder devices (TED's) used in South Pacific and Atlantic fisheries. This innovation has vastly decreased the bycatch (fish such as hake and rockfish) of Oregon's shrimp fishery while not affecting the efficiency of shrimp production.
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This hopper holds the port side catch
(no BRD used)
The catch is mixed with large hake, rockfish, and shrimp
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This hopper holds the starboard side catch
(BRD used)
The catch is primarily shrimp, few small hake, and occasional small rockfish are mixed in |
Bycatch reduction video
This research video shows the effectiveness of bycatch reduction devices (or BRDs) used in the Oregon pink shrimp fishery. The camera shows the face of a BRD (the silvery grate you see in the left side of the frame) located in the throat of a shrimp trawl net. The device is used to exclude fish from the shrimp catch. In the video you will see eulachon smelt and Pacific hake escaping from the net. The effectiveness of BRDs, other modifications to the design of shrimp trawl nets, and close management by the Oregon Department of Fish & Wildlife, made the Oregon pink shrimp fishery the first shrimp fishery to be certified by the Marine Stewardship Council as sustainable.
See the bycatch reduction device in action |
As seen in the diagram below, after fish and shrimp are directed into the opening of the fishing net they are funneled toward the back. As they travel toward the end of the net, they are forced down by the guiding panel aimed straight at the excluder. When they reach the excluder they are either forced up and out (larger fish) or allowed in (shrimp).
The BRD’s effectiveness relies on a guiding panel (encouraging proper water flow), then the escape exit, where unwanted catch exits the net. The BRD’s are typically circular or rectangular with vertical bars which are required to be no more than 3/4 inch spacing.
| This picture shows all catch from a shrimp haul using a 1.25 inch rigid-grate BRD. As you can see, the bycatch (in the two containers to the right) is a small fraction of the shrimp catch (all the other baskets pictured). |
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