The anadromous form of sockeye salmon Oncorhynchus nerka (O. nerka) is functionally absent and possibly extinct from the Deschutes River Basin.  Artificial barriers to fish movement including the Pelton Round Butte Hydroelectric Project (PRB Project) which was completed in 1964 on the Deschutes River (rkm 161 - 178), are among the factors contributing to potential sockeye extinction.  The PRB Project is owned and operated by Portland General Electric Company (PGE), an Oregon corporation, and the Confederated Tribes of the Warm Springs Reservation of Oregon (CTWSRO).  In 2005, the Federal Energy Regulatory Commission (FERC) granted PGE and CTWSRO (the Licensees) a new 50-year operating license (FERC License No. 2030-077).  In 2004, a Settlement Agreement concerning the re-licensing of the PRB Project was made by and among the Licensees and 21 other Parties.  The Settlement Agreement includes provisions for a Fish Passage Plan to: 1) establish self-sustaining harvestable anadromous fish runs of Chinook salmon, steelhead and sockeye salmon above the PRB Project; and to 2) provide for safe, timely and effective upstream and downstream fish passage of adult and juvenile life stages of several fish species including sockeye salmon.  Achievement of these two agreement provisions is a shared responsibility among the CTWSRO, PGE and the Oregon Department of Fish and Wildlife (ODFW) because CTWSRO and PGE are co-licensees and CTWSRO has co-management authority with ODFW regarding fish and wildlife in the Deschutes River Basin.  Within the Deschutes River subbasin, CTWSRO, PGE and ODFW conduct O. nerka investigations both cooperatively and independently.  This project has been developed to support information and data sharing.

Self-sustaining populations of resident O. nerka persist in the Round Butte Dam pool known as Lake Billy Chinook (LBC).  Additionally, Suttle Lake, the historic Deschutes River Basin sockeye nursery lake in the upper Metolius River Basin, holds a self-sustaining O. nerka population.  The O. nerka populations in each of these lakes offers an opportunity to restore an anadromous sockeye population.  Smolt-sized fish already attempting to emigrate from these two lakes above the PRB Project may be used to re-establish the sockeye run.  Such restoration would focus on preserving or potentially enhancing genetic fitness of these populations.  Due to completion of fish passage improvements at the PRB Project in 2009, annual springtime emigrations of juvenile O. nerka from LBC into the Deschutes River have occurred since 2010.  Each year since, a portion of these juvenile fish have returned to the PRB Project as adults.  Effects of continued juvenile O. nerka downstream passage on establishment of self-sustaining harvestable adult sockeye salmon runs is still being assessed by fisheries managers.

Project study objectives are designed to address information needs in the Deschutes River Basin for O. nerka ecology and life-history.  Such information informs fisheries management decisions.  Given study findings to date, three past objectives will not be included this year.  For example, few Suttle Lake O. nerka outmigrant smolts survive beyond a distance of 1 - 2 km from the lake and smolt survival to Lake Billy Chinook's Round Butte Dam is rare. Therefore, objectives to determine fate of Suttle Lake O. nerka outmigrant smolts in upper Lake Creek and their survival to Round Butte Dam have been met.  Also, an objective to estimate the number of O. nerka in LBC during November/December using mobile hydroacoustic survey techniques will be discontinued this year based on correlations with other study findings (objective 2, below).  For example, wintertime hydroacoustic survey results for medium size limnetic fish abundance estimates correlate with abundance estimates for O. nerka spawners determined by the mark-recapture study (objective 2, below) the following spawning season.

Information needs for LBC and Suttle Lake O. nerka to be addressed for 2020 include:

1) Estimate the timing and abundance of O. nerka emigrating from Suttle Lake during springtime using a smolt trap on Lake Creek;
2) Estimate the number of resident O. nerka spawning in the Metloius River Basin during fall using mark-recapture population estimate techniques; and,
3) Determine genetic structure and assess population relatedness of O. nerka in the Deschutes, Metolius and Columbia River Basins.  (CTWSRO personnel will collect O. nerka tissue samples from adult sockeye salmon captured at the Pelton Adult Fish Trap at Re-regulating Dam).  Genetic analysis will be conducted by geneticists at Columbia River Inter-Tribal Fisheries Commission (CRITFC)).