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ISMP backwater sampling evaluation C Appendices N and V). Over the study period, an average of 54 % of the cyprinids that occurred in backwaters were removed on the first sampling pass. On the second and third sampling passes, an additional 21 and 12 % of the total number of cyprinids were removed from backwaters, for a total of 87 % over the three removal sampling passes. First pass removal rates for cyprinid species were slightly higher in 1997 than in 1998, but average total removal rates were similar among years. Over the study period, an average of about 50 % of the green sunfish that occurred in backwaters were removed on the first sampling pass. An additional 30 and 12 % of the estimated total number of green sunfish in the backwater were removed on subsequent passes, for an average total removal rate of 92 %. Apparent removal rates were even higher for largemouth bass, averaging 58 % on the first pass and nearly 98 % over all passes. The estimated proportion of centrarchid fishes removed by depletion sampling may be somewhat inflated because the estimated proportion of fish removed was sometimes 100 % for backwaters where those species were rare and all specimens were captured on only a single sampling pass. However, depletion sampling conducted by electrofishing in backwaters 23 and 24 in 1998, where centrarchids were abundant, suggested that 48 % of green sunfish and 60 % of largemouth bass were removed on the first pass. A total of 87 % of the green sunfish and 94 % of the largemouth bass were removed with three depletion sampling passes, which suggested that average removal rates calculated over all backwaters were reasonably accurate. Fish community and habitat relationships Presence of largemouth bass and green sunfish in backwaters was generally positively associated with backwaters that were large and relatively deep, and were negatively associated -17-