Contract Description:
The Confederated Tribes of the Colville Reservation (CTCR) Resident Fish RM&E project is a Columbia River Fish Accord project that began in 2008. The primary goal for the Resident Fish RM&E Project is to conserve, enhance and restore native fish populations on the CTCR Reservation and Usual and Accustomed areas (UA), and when appropriate, provide opportunities for subsistence harvest by the Colville Tribal members and recreational anglers. The current work of the RM&E project focuses on the protection and conservation of Upper Columbia Redband Rainbow Trout.
Rainbow Trout are a focal species in the Sanpoil Subbasin under the Intermountain Province Subbasin Plan (IMP) due to their recreational value as a sport fish and their cultural significance to the CCT (Gillin and Pizzimenti 2004). The Columbia River Redband Trout are a subspecies of Rainbow Trout native to the Columbia River drainage east of the Cascade Mountains as far as barrier falls on the Snake, Spokane, Pend Oreille, and Kootenai rivers (Allendorf et al. 1980; Behnke 1992; McLellan and Lee 2010). Effective fisheries management of Redband Trout requires an understanding of population structure, historical management activities, geographic distribution, life history strategies, genetic diversity, harvest estimates, juvenile recruitment and adult escapement (Small et al. 1998; McCusker et al. 2000; Spidle et al. 2003; Spruell et al. 2003; Small et al. 2007).
Two genetically distinct subspecies of Redband Trout have been identified within the Sanpoil Subbasin (Small and Dean 2006, 2007). The Sanpoil River supports the largest Redband Trout population in the Lake Roosevelt watershed. In order to properly conserve and protect the Sanpoil River populations, and other native Redband Trout populations on and near the CTCR Reservation, an understanding population dynamics is necessary along with an estimates of survival during key life stages. This project will implement four tasks to assist with the management of Redband Trout in Lake Roosevelt, which includes: monitoring recruitment, monitoring harvest, monitoring movements/entrainment, and monitoring escapement.
The multi-year data set will enable managers to monitor trends over time and address potential limiting factors.
Monitoring Recruitment: PIT tag arrays and a screw trap will be used to estimate Redband Trout juvenile recruitment, including age and timing, to Lake Roosevelt from the Sanpoil River basin. Two full duplex PIT tag arrays will be operational all year long. One located at the mouth of the Sanpoil River, and one located at the mouth of the West Fork Sanpoil River.
Monitor Harvest: The project will coordinate with the Lake Roosevelt Fisheries Evaluation Project (1994-043-00) to obtain creel information on wild Rainbow Trout capture and harvest. Creel clerks scan all wild Rainbow Trout for PIT tags. Tissue samples and otolith samples will be collected from all wild Rainbow Trout during creel surveys. If funds are available, DNA analysis will be conducted to determine the proportion of wild trout harvest from the Sanpoil River or the other 30 tributaries currently in the DNA database.
Monitor Escapement: The project will monitor lacustrine adfluvial escapement into the Sanpoil River from a weir trap installed near the mouth of the river. Current monitoring is restricted to the summer and fall, as the weir cannot currently withstand the spring freshet. The mainstem PIT tag array will also be used to track river entry timing of adult spawning fish. At least 1,000 DNA tissue samples will be collected for adult returns over multiple years to monitor and identify the tributaries that have the highest survival of juveniles to adults.
Monitor Movements/Entrainment: We will coordinate data sharing with the Spokane Tribe of Indians, who currently maintains the other acoustic receivers in Lake Roosevelt. Entrainment of adult and juvenile Redband Trout downstream of Chief Joseph Dam will be monitored via PTAGIS. Lower river bypass facilities upload their PIT tag data to this website which allows us to query for tags we placed in fish.
The development of a standardized stock assessment project has enabled regional biologists to estimate the current status of Redband Trout in Lake Roosevelt relative to management targets. These estimates have been used to suggest management activities to improve abundance of Redband Trout in the Sanpoil River and Lake Roosevelt. The information will be used to conserve and protect high risk populations, which are those that have less than 100 breeding pairs, identify the most productive locations which will enable biologist to suggest protection actions.
Data obtained during this year study will be combined with co-manager data and used by the co-managers as a tool for conserving Redband Trout in the Upper Columbia River basin. The results will also be used in concert with the CTCR Habitat Improvement Project to monitor changes in the population status after habitat projects have been implemented throughout the Reservation and UNAs.
For example, data from this project was used to verify that the Sanpoil stock of Redband Trout were being overharvested in the fishery, which led to a catch and release only rule within Lake Roosevelt in 2016. Since that time, monitoring data has indicated an increase in both juvenile and adult returns, ensuring resiliency is being built into the population. This is important as the population will need to combat consequences related to climate change, primarily warming water temperatures and loss of habitats due to wildfires.