This project seeks to expand our knowledge on the factors limiting production of Okanogan and Wenatchee sockeye salmon stocks.  A primary factor affecting the Okanogan stock is believed to be survival upstream of Wells Dam.  To quantify this mortality, this project has funded PIT and acoustic tagging of sockeye salmon at Wells Dam with additional sockeye PIT tagged at Bonneville Dam as part of the Upstream Migration Timing Accords project).  The project also funds an acoustic tag antenna network upstream of Wells Dam and additional PIT tag antenna arrays at Zosel and dam and at Oliver, BC.    Between the acoustic and PIT tags, Okanogan sockeye salmon mortality will be partitioned by reach upstream of Wells Dam and we hope to then be able to correlate survival with river and lake conditions, hopefully allowing survival to be increased through better Okanagan River management.  

This project also seeks to standardize smolt abundance estimation methodologies between the two stocks by conducting annual hydroacoustic surveys of Lake Wenatchee to compare with those being conducted in Osoyoos Lake.  

This project will expand our Upstream Migration Studies project (2008-518-00) by funding deployment of PIT tag detection antennas as well as an acoustic tag network in the Okanagan Basin.  This will allow sockeye salmon to be tracked through the Okanogan Basin, thereby allowing us to extend our migration survival estimates into the Okanogan River.  We also will be able to determine where in the Okanogan River-Osoyoos Lake mortality is occurring, which may then allow for the development of different river management actions to reduce this mortality.  It is hoped that, depending on where mortality is occurred, better flow management techniques to optimize adult survival can be developed.  The PIT tag network we develop as part of this project may also improve data on steelhead and Chinook use of the Canadian portion of the Okanogan Basin.