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B. River sampling 1993 The White River was divided into upper and lower reaches for sampling. Each sampling reach was 8 km (5 miles) long. The upper reach began 0.5 km below Taylor Draw Dam and went downstream (RK 167-159). The lower reach was selected as RK 127-119 because of the location of an access point at RK 121.6. However, due to good navigability the actual length electrofished was RK 130- 116. Two sampling methods were used on the river: electrofishing and baited hoop nets. Electrofishing was conducted using an 5.5 m (18 foot) jet powered, flat bottom boat with a three person crew. The electrofishing equipment consisted of a 5,000 watt portable generator, a VVP 15, two spherical anodes, and 15.2 m (50 feet: in 8 and 9 ft sections) of trailing steel cable cathode. Hoop nets were two 0.8 m diameter x 3.6 m long and-two 1.1 m diameter x 4.6 m long nets with two throats each. The electrofishing procedure was to move slowly downstream along one shoreline of the river in a sampling reach. When this was completed, the other shoreline was sampled starting again from the upstream end of the reach. Channel catfish were captured using long handled dipnets and placed in alive tank for data processing. Other fish species encountered were not collected or counted. Various settings in DC pulse were used on the voltage pulsator in an attempt to improve the catch of channel catfish. A low voltage and amperage technique (<200 volts, 3 amps, 70-80% pulse width, and 20 pulses per second) that has been used successfully in Arizona on flathead catfish (Brad Jacobson, personal communication, Arizona Game and Fish Department, 1993) was tried numerous times. However this technique was eventually discontinued because it did not improve catch rates of channel catfish. A voltage pulsator setting of 190-200 volts, 3 amps, 20% pulse width, and 60 pulses per second appeared to most consistently produce channel catfish and was used the majority of the time. Electrofishing was conducted July 7-8 and 12-15. Effort was measured in seconds of operaton by a timer on the voltage pulsator and later converted to hours. Hoop nets were set in slow moving pools that were deep enough to cover the hoops. Bait was mackerel flavored cat food, carp chunks, or fresh shrimp. Sampling occurred July 7-9, 13-15, and September 1-3. Hoop nets were fished for 24 hours. All channel catfish captured by electrofishing and in hoop nets were examined for an adipose fin clip, measured for TL, weighed on a platform spring scale, and released. Channel catfish longer than 300 mm TL received an individually numbered Floy tag. At the recommendation of Tom Pellett (personal communication, Wisconsin Department of Natural Resources, March 8, 1993) the minimum 300 mm size to Floy tag river fish (as compared to 250 mm in the reservoir) was done to increase survival of tagged fish in the riverine environment. Channel catfish shorter than 300 mm 7