Keith evaluated the effects of past and future trends in temperature and discharge in the Okanogan River on the migratory performance of the Upper Columbia River population of sockeye salmon (Oncorhynchus nerka). Fish of lower condition exhibited disproportionately higher mortality during the spawning run, elucidating a critical link between energetic condition and a fish’s ability to reach the spawning grounds. We evaluated habitat conditions and spawning migrations in the population from the time of entry into the Okanogan River to arrival on the spawning grounds (about 1,200 km upstream).
The thermal TIR and LiDAR output indicates relatively high interannual variability in habitat quality, quantity and in ecosystem integrity in recent years related to unusually high discharges (e.g., 1997) and warmer than average water temperature (e.g., 1998). We examined how global climate change might affect discharge, water temperature, and the energy used by sockeye salmon during spawning migration.