The direct-proportion method was used to estimate fish populations in Areas 1, 3 and 6. Reliable results could not be obtained for all species because of scarcity, mortality in handling, mobility, or other factors. A high rate of mortality due to handling was observed in Area 1 for the red shiner and in Area 6 for river carpsucker (young-of-the-year), sucker-mouthed minnows, red-finned shiner, red shiner, blunt-nosed minnow, and stoneroller. In Area 3, in contrast, there was little mortality in the same species during the twelve-hour interval that fish were held in traps prior to release as marked individuals. The following species were common in at least one area, but probably are sufficiently mobile (see page 416) to invalidate estimates of static populations in small areas: red shiner, red-finned shiner, and channel catfish (yearlings and older). Other species were rare and are indicated as "T" in Table 13. Those species for which population-estimates seem warranted include: golden redhorse, sucker-mouthed minnow, red shiner, sand shiner, fat-headed minnow, stoneroller, stonecat, channel catfish (young-of-the-year), green sunfish, long-eared sunfish, slender-headed darter, and orange-throated darter. I consider the estimate valid if a high percentage of the marked fish is recaptured. Results are presented in Table 15, and ordinarily will not be referred to in the following discussion of the population in each of the three areas. _Area 1_ The order of abundance at Area 1, in terms of the estimated population per 500 square feet, was as follows: stoneroller (47.6), stonecat (29.4), channel catfish (young-of-the-year) (20.6), green sunfish (19.4), red shiner (18.2), long-eared sunfish (9.4), channel catfish (yearlings and older) (6.5), golden redhorse (1.2). Insufficient data make inclusion of other species unreliable.