PROGRESS REPORT FOR INVESTIGATIONS ON BLUE CREEK FT 1992 ABSTRACT The U.S. Fish and Wildlife Service, Coastal California Fishery Resource Office in Arcata, California, was funded to investigate chinook salmon roncorhvnchus tshawvtschav spavming use, juvenile salmonid emigration, and characterize stream habitats in Blue Creek, a tributary to' the Klamath River; California. Investigations began in October 1988, with this reporting period covering October 1991 through September 1992. Adult chinook spawner escapement was addressed by surveys of redds, live fish and carcasses, and by radioteleiretry. Spawner numbers were v?ry low, with only 22 redds observed in fall 1991/winter 1992. The peak count of adult Chinook was 97 fish in early November. Radiotelemetry of migrating spawners (n?8) was used to locate remote spawning areas. Emigrating juvenile Chinook salmon, steelhead trout 10. mvkissV/ coho salmon (fi. kisutchl. and coastal cutthroat trout (g. clarltiV were trapped at river kilometer (rkm) 3.35 with a rotary screw trap (screw trap). The trapping period extended from April to July for a total of 75 trapping nights. Screw trap catches totaled 10,688 chinook, 1,388 steelhead, 99 coho and 10 cutthroat. Peak Chinook emigration occurred during the week of May 17, which is consistent with the past 3 years of monitoring. A juvenile weir was operated 58 nights, and caught a total of 9,166 chinook, 1,196 steelhead, 127 coho and 1 cutthroat. The index of abundance for emigrating chinook during the 1992 juvenile trapping period was 49,590. Sixty-five percent of the juvenile chinook caught during the trapping season were marked with coded wire tags (n-12,687) and released back into Blue Creek at rkm 3.3. Mean water temperatures varied from 6.3 to 18.6 XI and stream flows ranged from 43 to 2178 eft (1.3 to 61.7 m3/?) during the Fiscal Year (FY) 1992 study season.
Report AFF 1-FRO-93-12