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<br />562 <br />2. Characterize physical attributes of secondary channels <br />a) seasonally <br />b) longitudinally (including by geomorphic reaches) <br />c) relative to overall dimensions <br />d) relative to physical attributes of primary channel <br /> <br />3. Evaluate potential of secondary channels to provide habitats needed/used by native fishes, <br />particularly Colorado squawfish and razorback sucker. <br />a) do current biotic and abiotic attributes of secondary channels diminish or <br />enhance their suitability for native fishes? <br />b) do secondary channels provide "essential" habitat for specific life stages of <br />native and nonnative fishes? <br />c) identify potential management actions to enhance suitability of secondary <br />channels for native fishes. <br /> <br />In addition to data collected by NMGF personnel, data from 1) secondary channel emigration! <br />emigration studies (USFWS-NMFRO); 2) adult monitoring studies (USFWS-CRFP); 3) <br />razorback and Colorado squawfish telemetry (USFWS-CRFP, Miller Assoc.); 4) early life history <br />studies (UDWR, UNM); 5) nonnative food habits studies (USFWS-NMFRO); 6) geomorphic <br />characterization (K--B); 7) river channel dynamics (K-B); 8) habitat mapping and resource <br />utilization studies (K-B); and 9) flow/habitat modeling (K-B) will be used in preparation of report <br />on biotic and abiotic seasonal and longitudinal characterization of San Juan River secondary <br />channels fish communities. Appropriate univariate and multivariate statistical procedures will be <br />used in data analysis. <br /> <br />While the secondary channel inventory work was designed to investigate fish communities from a <br />system level, the permanent sites study was a finer-scaled study. To accomplish this, sampling <br />frequency and intensity was greater than that for the characterization study. The permanent site <br />study also involved collection of habitat use and availability information. <br /> <br />Specific study objectives ofthe secondary channel permanent site study were: <br />1. Characterize dynamics of the fish community in four representative secondary channels. <br />One channel had surface flow throughout the year; a second had interrupted surface flow; <br />the third had no surface flow during flow-flow periods and habitat consisted only of <br />isolated pools; and the fourth was mainly standing-water habitat during low flow periods <br />but often had surface flow during and following storm events in the low-flow season. <br />a) characterize the fish community of each permanent site in relation to season <br />and flow regime <br />b) characterize habitat-use patterns of each fish species (including by life <br />stage) present at each permanent site <br />c) characterize life history strategies of each fish species in secondary <br />channels <br />d) characterize species interactions in secondary channel habitats. <br /> <br />22 <br />