The USFWS contract supports two objectives for Project 1993-056-00 (Advance Hatchery Reform Science): 1) Improve survival and reduce fitness loss in Columbia River steelhead smolts by minimizing unnatural selection on body size and other smolt characteristics, and 2) Identify behavioral and physiological traits under selection through laboratory-scale research.

In the FY25 performance period, staff of the USFWS will collaborate with NOAA on the following activities in support of the two project objectives.

Objective 1:

Finding an effective rearing method that maximizes smoltification without accelerating maturation is key to reducing domestication which is strongly associated with fitness loss of hatchery reared steelhead.  Project 1993-056-00 has raised several brood years of age-2 steelhead smolts at the WNFH in standard raceways, and at the NOAA Manchester Research Station in circular tanks, but achieved very different results.  Age-2 steelhead raised in circular tanks at Manchester have significantly lower precocious maturation rates and higher rates of smoltification than steelhead reared at WNFH.  In the FY24 performance period the USFWS and NOAA determined it was feasible to install circular tanks at the WNFH for a pilot study, NOAA transferred the necessary rearing tanks to the USFWS, and the USFWS started preparations for a pilot study using circular tanks for rearing age-2 steelhead.  

In the FY25 performance period, the USFWS and NOAA will install the remaining tanks, and begin rearing age-2 steelhead smolts for the pilot study.  The age-2 smolts will be assessed in the FY26 performance period when they are ready for release. Infrastructure upgrades are scheduled for the WNFH in the near future and include replacement of some aging concrete raceways with large circular rearing vessels. If rearing in circular tanks improves smoltification and reduces maturation, as seen at the laboratory-scale experiments at Manchester and pilot-scale experiments at the WNFH, the new circular tanks at WNFH may also improve survival and reduce fitness loss in these populations of summer steelhead.  The pilot study will provide guidance to scale up production of age-2 smolts upon completion of the infrastructure upgrades and reduce the risks (poor growth, survival, or smoltification) associated with abrupt changes to established raceway rearing practices.  

Objective 2:

In FY25, the USFWS will continue to provide steelhead obtained from natural-origin broodstock for the laboratory studies to determine behavioral and physiological traits under selection in hatcheries.

The USFW service will also continue to collaborate in data analysis and the production of manuscripts based on the data collected from the hatchery- and laboratory-scale studies.