Forest Service Comment: Under Water Quality Measurements and Habitat Observations, it is noted that the average width, depth and gradient and maximum depth of the sampled reach will be estimated. Will there be any calibration of these estimates to establish accuracy?

Edison Response: The "estimates" will be based upon actual field measurements:

• Widths will be measured at five cross-sections for each study area (i.e. electrofishing reach or snorkel pool): bottom, 1/4, 1/2, 3/4, and top. Average width estimate will be based upon the mean of the five measurements.
• Mean depth will be computed across the same transects listed above by taking depth readings (to nearest 0.1 foot) at the 1/4, 1/2 and 3/4 widths across the stream. This will give fifteen depth readings (3 depth readings per transect times 5 transects). These fifteen readings will be summed and divided by 20 (because we assume depths of zero for each transect at the streambanks). This average depth estimate follows the guidelines of Overton, C.K., M.A. Radko, and R.L. Nelson. 1993. Fish habitat conditions using the Northern/Intermountain Regions' inventory procedures for detecting differences on two differently managed watersheds. USDA Forest Service GTR-INT-300. Ogden, UT.
• Gradient will be measured using a clinometer.
• Maximum depth will be the greatest measured depth in a particular study area (electrofishing reach or snorkel pool).

Edison Response: Each diver will have and be familiar with a reference string attached to their wrist data slates. These strings will be knotted along their length at 75 mm, 150mm, 300 mm and 400 mm from their origin. Individual snorkelers can then refer to these calibrate strings during their dives to help validate their length estimates.During the "training dive" of the non-sample pool unit, each diver will be asked to categorize a series of plastic fish silhouettes of known length (to the trainer) into the appropriate size categories proposed for the Kern studies. Divers that consistently mis-categorize fish will be given more intensive size evaluation training, until they can satisfactorily discriminate the size classes.Forest Service Comment: Finally, under the Technical Report heading, there is no mention of determining age classes of the fish sampled. Age class information could be valuable in identifying possible bottlenecks within the fish association.Edison Response: Primary age-class determinations will be made using the length-frequency distributions for each of the species. A subsample of the bass and hardhead will have scales samples removed and available for additional analysis if necessary.�

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