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38 marked fish, The mouth of the backwater (see Figure 12) was too deep to seine. The middle part was seined several times and depths and bottom type suggested an efficient sample except that the entire width could not be sampled in one sweep. Only a few young-of-the-year squawfish were found here. The upper part was thoroughly sampled from bank to bank and produced the majority of the young-of-the-year squawfish. Samples from other backwaters also indicated a preference for upper portions of back- waters with a relatively shallow depth. Therefore, sampling efficiency was excellent in the upper portion of the backwater, good in the middle part and poor or non-existent near the mouth. If just the upper portion is analyzed, a large turnover of squawfish young is indicated. The question remains, what happened to the marked fish? It is possible they died from the marking and handling process. This is ex- tremely doubtful due to the great amount of caution used in handling the fish and the small amount of anal fin actually clipped, Another explanation is that the fish moved considerably, either within the backwater, or between that area and other habitats in the im- mediate area. As mentioned earlier, an intense effort was made to locate the marked fish, especially downstream from the sample backwater. The area above and below the backwater was very deep, which prohibited sam- pling other than very close to shore (Figure 12). Failure to find marked squawfish, or any young-of-the-year squawfish for that matter, in these adjacent areas suggests either the small fish used the main channel, which is highly unlikely, or moved considerably within the sample back- water, It would appear the latter possibility is the most likely, The