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Abstract
The point at which fish use ends represents a key ecological and regulatory demarcation on state and private forest land in the Redwood region. Currently, the end of fish use and other key demarcations with stream classification are measured or estimated based on judgments of Registered Professional Foresters and aquatic biologists with little guidance from empirical study of the issue in this region. This study establishes a standard protocol for the detection of the end of fish use in streams, which reduces the effort required to produce quality data. During electrofishing the maximum distance traveled between fish presence in delineated habitat units was 289 m. This distance decreased as the slope of the channel increased. In 63 percent of the streams the distance was less than 20 m and in 96 percent the distance was less than 100 m. Fish were found in all habitat units the most abundant was pools at 56 percent of the time. This study has indicated that a pool based method will not give an accurate indication of the end of fish use in streams. A more accurate method should be based on distance were the all habitat units are shocked. In streams with low gradient a minimum of 300 m should be surveyed during the study. In streams were a gradient break of a minimum of eight to12 percent exist this study has indicated the 60 m is sufficient to survey to indicate the Class I, Class II break.
Parent Publication
Citation
Bliesner, Aaron K.; Robison, E. George. 2007. Detecting the Upstream Extent of Fish in the Redwood Region of Northern California. In: Standiford, Richard B.; Giusti, Gregory A.; Valachovic, Yana; Zielinski, William J.; Furniss, Michael J., technical editors. 2007. Proceedings of the redwood region forest science symposium: What does the future hold? Gen. Tech. Rep. PSW-GTR-194. Albany, CA: Pacific Southwest Research Station, Forest Service, U.S. Department of Agriculture; p. 135-146
