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6 <br />and seining was attempted. It was found that a small, bag seine, 15 ft x 4 ft <br />(4.5 m x 1.2 m) with 15 mm stretched mesh yielded the best results in slow <br />moving and back water areas. Because of the high turbidity of the river, <br />shocked fish could not be easily observed. It was determined that a combin- <br />ation of seining and electrofishing with either a generator (Olsen 240 v) <br />located on the bank, or a backpack shocker (Coffelt 12 v DC battery pack) <br />yielded best results during normal and low flow conditions. Sampling protocol <br />with this gear combination was as follows: the seine was stretched from the <br />bank toward the center of the river and electrofishing began approximately <br />30 ft (10 m) upstream from the seine and progressed downstream. Narcotized <br />fish and those attempting to avoid the electrical field were captured as the <br />current carried them into the seine. The seine was then brought to shore. <br />This procedure was repeated along approximately 1000 ft (300 m) of shoreline. <br />At each station 300 m of shoreline were sampled in this way. If larval <br />rearing areas were present at the sampling station, one or more sites of this <br />kind of habitat were also sampled. When spring runoff caused flooding (May <br />and June), sampling was conducted almost exclusively using an electrofishing <br />boat. A 17 ft (5.1 m) flat-bottom boat equipped with a 40 hp outboard motor <br />and 240 v generator was used. Electrofishing was conducted using 240 v direct <br />current at a frequency of60 cycles per minute. <br />Sampling was generally ineffective because of the high turbidity and <br />particularly so in areas where flow was great or where water depth was greater <br />than 6 ft (2 m), Greatest success was had in slow water areas such as <br />backwaters, below bars, downstream from debris, and along the bank. <br />All captured fish were identified and counted. Lengths of endemic fish <br />were determined and a.ll fish, except those that could not be identified <br />because of their small size, were returned to the river. Unidentified speci- <br />mens were preserved and returned to the laboratory for species determination.