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ISMP backwater sampling evaluation surface area, had minimum depth of 10 cm if turbid or 30 cm if clear, and were not flowing, as per ISMP selection standards. Each backwater was blocknetted at the mouth and the fish community sampled with two non-overlapping ISMP seine hauls (Fig. 3). The hauls were typically made near the mouth and nearer the apex and were usually transverse to the long axis of the backwater. Fish in ISMP samples were identified and enumerated in the field or preserved in 10 % formalin for processing in the laboratory. Area seined was measured. The backwater fish community was then sampled again using a more intensive 3-pass seine depletion or capture-recapture approach. In seine depletion backwaters, seine hauls (4.6 m long seine, 3 mm mesh) were made in sufficient number to sample nearly the entire area of the backwater on each of three passes; the same number of seine hauls (effort) was made on each sampling pass. Fish captured on each pass were placed in separate live baskets and were enumerated or preserved for laboratory analysis when all sampling passes were completed. Before preservation all samples were scanned for native fishes which were enumerated and released. Preserved samples were identified and enumerated at the Larval Fish Laboratory, Colorado State University, Fort Collins. Capture-recapture sampling involved capturing fish on one or two consecutive days (passes) with some combination of seining or fyke nets and was followed with a final pass which employed fyke nets, electrofishing, or both. Fyke nets were used in 1997 but were found relatively inefficient because they captured few fish, were size and species selective, and hence, were not used in 1998 sampling. Green sunfish and largemouth bass sampled on all but the final pass were marked with a unique fin clip. In backwaters where capture-recapture sampling was employed, other fish species were incidentally captured and enumerated and were included in -4-