Non-native salmonids are impacting native salmonid populations throughout the Pend Oreille Subbasin. Competition, hybridization, and predation by non-native fish have been identified as primary factors in the decline of some native bull trout and cutthroat trout populations. Therefore, the goal of this project is to implement actions to suppress or eradicate non-native fish in areas where native populations are declining or have been extirpated. These projects have been identified as critical to recovering native bull trout and westslope cutthroat trout (WCT).

Lower Graham Creek was invaded by non-native rainbow and brook trout after a small dam failed in 1991. 700 m upstream of the mouth of Graham Creek, a few boulders have currently limited upstream invasion of non-native fish.  However, this section of stream will likely be breached by non-natives if the boulders are shifted by high flows, bank failure, etc.  By 2003, no genetically pure WCT remained in the lower 700 m of Graham Creek and only pure westslope cutthroat were sampled above the barrier at 700 m.  In July of 2007, a fish management structure will be constructed at the mouth of Graham Creek to preclude further invasion of non-native fish into Graham Creek. Electrofishing was completed in the lower 700 m to remove and relocate all captured fish below the new barrier site.  Monitoring of the lower 700 m will occur in July 2009 to ensure no fish are breaching the barrier.

Westslope cutthroat trout have recently been extirpated in Cee Cee Ah Creek due to displacement by brook trout. In 2008, Cee Cee Ah Creek will be treated with rotenone to eradicate brook trout. Another rotenone treatment is planned for 2009 to ensure that eradication is successful.  Once eradication is complete, cutthroat trout will be translocated from nearby watersheds.  Re-invasion of the treatment area is impossible due to the Cee Cee Ah Falls.  Much of the effort in 2007 was made towards public education and involvement in using piscicides for native fish recovery.  To date, public acceptance of using piscicides as a management tool has been accomplished.