Columbia River steelhead are iteroparous (able to spawn multiple times). However, as post-spawned steelhead (kelts) attempt to migrate downstream to return to the ocean, their survival is adversely affected by major dams. Therefore, an innovative approach to effectively increasing abundance and productivity of steelhead populations is to capitalize on their inherent iteroparity by reconditioning kelts. Reconditioning is the practice of capturing, holding, and feeding post-spawned steelhead in an artificial rearing environment for the purpose of regenerating vigor to enable repeat spawning. The Yakama Nation, in cooperation with the Columbia River Inter-Tribal Fish Commission, is managing a reconditioning project aimed at increasing the survival and potential repeat spawning rates of Yakima River steelhead kelts.
The questions we are addressing in this research are:
- What feed types result in growth and re-maturation of gonads when rearing kelt steelhead in a captive environment?
- Do captive kelts grow and survive?
- Is abundance of potential repeat spawners better enhanced by a short- or long-term reconditioning program?
- Do short-term kelts migrate successfully through the lower Columbia River?
- Do long-term reconditioned kelts migrate to the spawning grounds?
The ultimate goal is to determine whether—and if so, to what extent—steelhead kelt reconditioning can contribute to increases in the abundance, productivity, spatial distribution, and diversity of Yakima Basin steelhead populations.
Wild steelhead kelts from the Yakima River are captured during their migration past Prosser Dam and through the Chandler Canal. These kelts are held in circular tanks at Prosser Hatchery for up to 10 months. Short-term reconditioned kelts are feed for up to two months at Prosser and then transported to the lower Columbia (below Bonneville Dam) and released. Long-term reconditioned kelts are released to the Yakima River below Prosser Dam, coicident with the peak of the upstream steelhead migration. This allows reconditioned kelts to naturally move upstream, select their spawning location, timing, and mates.
See project downloads.
For linked project description see: http://www.cbfish.org/Proposal.mvc/Summary/RMECAT-2007-401-00 and
For latest annual report see: https://pisces.bpa.gov/release/documents/documentviewer.aspx?doc=P127171