Finding Sustainability Through a Fish Factory Addiction: The Development of Stock-selective Gear-types
If society refuses to cease its dependence on hatchery production — a practice widely recognized as one of the primary contributors of the decline of wild salmon and steelhead — the development and implementation of terminal, stock-selective harvest strategies remains the only avenue to resolve the inevitable tragedy of mixed-stock fisheries (where ESA-listed fish are caught along with the targeted, non-listed salmon or steelhead). While hatchery-origin fish demonstrate substantially reduced marine survival relative to their wild cousins, the sheer quantity of smolt releases from fish factories ensures that thousands of domesticated fishes usually return to Washington State rivers annually. If commercial and recreational fishers fail to capture the facility-raised salmonids on their homeward migration, genetic introgression between hatchery and wild fish is destined to occur, undermining the genetic diversity, survival, and reproductive capacity of wild populations listed under the Endangered Species Act (ESA). Therefore, the existence of any hatchery program creates the need for substantial fishing effort in order to remove hatchery-origin fishes and prevent detrimental interactions with wild runs.
Nevertheless, utilization of conventional harvest strategies—specifically gill-nets—inflicts unacceptable rates of bycatch mortality on ESA-listed stocks, inhibiting salmon recovery. In order to resolve this unsustainable predicament, Wild Fish Conservancy and partners are working to develop terminal, stock-selective harvest strategies to enhance the harvest of hatchery produced fishes at their river of origin, while minimizing rates of bycatch mortality on threatened and endangered salmon and steelhead populations.
In 2013, Wild Fish Conservancy partnered with veteran commercial fisherman Blair Peterson and the Washington Department of Fish and Wildlife to develop the first pound-net fish trap on the Columbia River in over eighty years. Pound-net fish traps were once the most efficient harvest tools utilized in salmon fisheries of Washington State. Fixed into a river bed with pilings, pound nets employ a series of mesh leads that funnel the salmon into the trap “spiller” where fish swim freely prior to examination and harvest (if hatchery-origin) or release (if wild). Without tangling or wedging captured fishes, the gear has significant potential to reduce physical injury and many physiological issues arising from conventional harvest techniques. The success of this prototype has encouraged WFC to plan an evaluation of pound nets during the fall 2015 test season of the Lower Columbia River Basin’s commercial selective gear implementation program. Ultimately, the results will help determine whether the alternative gear-type is one solution to the predicament established by flawed hatchery and harvest management policies.
If conventional hatchery practices continue, problems resulting from overharvest and hatchery production will further limit wild salmon and steelhead recovery in the face of climate change. Through Wild Fish Conservancy’s efforts to develop stock-selective harvest strategies, problems arising from hatchery production and the use of non-selective gears may be minimized. Acknowledging that our thirst for the short-term benefits of fish factories may truly be an addiction, the immediate implementation of stock-selective gears is a necessary compromise that may in part remedy the tragedy of our mixed-stock fisheries.