The Osprey: Lower Columbia River Pound Nets
The cover story for this issue of The Osprey, “Commercial Fish Traps for Bycatch Mortality Reduction in Salmon Fisheries” by Adrian Tuohy of the Wild Fish Conservancy puts forward a potential solution for addressing the challenge of maintaining commercial salmon fishing in mixed stock fisheries while protecting wild fish — especially stocks listed under the Endangered Species Act.
The idea is to adapt traditional Native American fish traps to commercial fisheries by using them in place of gill nets. The fish are captured live in these “pound nets” that refer to the trap or “pound” in which they are caught. Then, the wild salmon and steelhead can be separated and released unharmed while hatchery salmon are retained for harvest.
The traditional commercial gill net fishery on the lower Columbia River, where the experimental fish trap was operated, has long been controversial since they are non-selective and result in high bycatch mortality. Resentment, especially from recreational Columbia River salmon anglers, has often run high against the gill netters. Over the decades there have been a number of unsuccessful attempts to ban commercial gill nets on the lower Columbia River either legislatively or through ballot measures. A more recent strategy is to develop hatchery-based terminal fisheries specifically intended for gill net harvest.
ALSO IN THIS ISSUE
• GREAT LAKES WILD STEELHEAD RESEARCH
• NORTH UMPQUA RIVER: GUARDING STEELHEAD AND A PROBLEMATIC DAM
• LETHAL COLUMBIA AND SNAKE RIVER WATER TEMPERATURES
In the Columbia River, which includes mixed-species runs that are often made up of both hatchery and ESA-listed wild salmon and steelhead, fishing seasons — both recreational and commercial — are largely driven by the incidental catch of protected wild fish.
Each run of wild fish has a maximum incidental catch mortality quota, so when a hatchery run is mixed with a wild fish run, the season is shut down when that incidental take quota is reached.
Commercial fishing typically has a higher rate of incidental bycatch mortality and reaches the quota faster than recreational fishing. Developing practical and cost effective ways to commercially catch fish with a lower wild salmon and steelhead bycatch mortality rate not only allows more wild fish to reach their upriver spawning grounds but also permits longer seasons for both commercial and recreational fishers along with a greater harvest of hatchery fish. It’s a win-win situation all around.
Finding ways to reduce bycatch mortality and overall waste of fish will help other river systems besides the Columbia. On the Fraser River system in British Columbia, for example, First Nations chum salmon gill net fisheries that focus on the harvest of females for roe results in the waste of large numbers of male chum. In addition, bycatch mortality is also a key factor in the decline of wild steelhead in the Fraser River basin, and on the Thompson River in particular.
Eventually developing better commercial fishing methods and putting them into widespread use will go a long ways to protect wild salmon and steelhead in mixed stock fisheries.