The Nez Perce Tribal Hatchery's (NPTH) goal is to restore self-sustaining Chinook salmon to their ancestral habitats in Clearwater River Subbasin. The Nez Perce Tribal Hatchery - Monitoring and Evaluation spring Chinook (Oncorhynchus tshawytcsha) Program is designed to provide adaptive management guidance at multiple life stages for both hatchery and natural fish segments. Supplementation benefits to be evaluated under the M&E program include increases in the distribution, abundance, and harvest of hatchery and natural Chinook salmon populations in the Clearwater River subbasin. To measure these benefits, changes in the abundance of Chinook salmon in tributaries to the Clearwater River will be monitored over the next 15 to 20 years. In addition to measuring project related benefits, the M&E Program is designed to provide information on the capacity of the natural environment to support Chinook salmon production, give early warning of adverse impacts caused by the project on resident biota, and track trends in environmental quality, management, and policy that may affect the project's success.
Results from M&E efforts will be used to determine whether desired results are being achieved, and to enable adaptive management. The M&E program examines the performance and status of hatchery and natural fish, species interactions and impacts to non-targeted fish populations, sustainability of harvest, and will communicate its findings to enable adaptive management of NPTH. The statement of work covers multiple aspects of Chinook salmon life history in all treatment streams. Treatment streams are Meadow Creek (Selway River), Lolo Creek, and Newsome Creek for spring Chinook salmon. Outcomes in these treatment streams will also be compared to those in similar non-treatment (reference) streams and other hatchery programs to help distinguish treatment effects from the effects of environmental variation between years.
The M&E Program assesses which NPTH supplementation strategies are best for supplementing natural, depleted, or non-existent spring Chinook salmon populations and what effect supplementation has on these and resident fish populations. The program will identify which of the supplementation strategies employed are beneficial in terms of increasing adult returns (to harvest and spawning streams) and the level of supplementation necessary to sustain specific levels of adult returns. Biological evaluation points include parr density, summer and winter survival to stream mouth, survival to Lower Granite Dam and other downstream dams, adult returns to weirs, spawning escapement, and pre-smolt and smolt yield from both treatment and control streams. Genetic monitoring of the treatment and reference populations will also occur.