. Bulletin. Natural history; Natural history. March, 1963 Larimore & Smith: Fishes of Champaign County 303 streams, a 50-foot electric seine, powered by an 11-ampere, 230-volt alternating cur- rent generator, was used. The generator was usually left near the equipment truck, and the electric lead wires were run off a reel having a commutator through which power was supplied as the electrodes were moved up and down the stream. In the blocked-off areas, we took 77 samples, all within a short period of time (July and August, 1959), thus keeping at a minimum the effects that seasonal changes i
. Bulletin. Natural history; Natural history. March, 1963 Larimore & Smith: Fishes of Champaign County 303 streams, a 50-foot electric seine, powered by an 11-ampere, 230-volt alternating cur- rent generator, was used. The generator was usually left near the equipment truck, and the electric lead wires were run off a reel having a commutator through which power was supplied as the electrodes were moved up and down the stream. In the blocked-off areas, we took 77 samples, all within a short period of time (July and August, 1959), thus keeping at a minimum the effects that seasonal changes in fish distribution and abundance might have on our samples. Because for each blocked-off area we made and kept a record of the number of individuals of each species in the sample and their total weight, we refer to a sample from such an area as a quantitative sample. To supplement the sample taken within each blocked-off area, we seined nearby habitats, figs. 2 and 3. An indefinite num- ber of hauls was made with a 20-foot by 4-foot nylon minnow seine of three-six- teenths-inch mesh. These "cruising" sam- ples usually added several species to the list of fishes taken at each locality. Ma- terial obtained outside the blocked-off areas was not included in the quantitative samples. Fish in the "cruising" samples were not measured or weighed. The reliability of our quantitative sam- ples was not determined. We recognized the selectivity of electrofishing in differ- ent habitats and for different species of fishes. For obvious practical reasons, we could not adapt our equipment and pro- cedure to produce the greatest efficiency. Fi<i. 3.— Seining a shallow pool in the Sangamon Ri\er near Mahdniei. Ilalntji- type contain suckers and minnows. In 1959, collecting with a minnow seine in such usually yielded species not collected with an electric seine in nearby blocked-off areas. ut this habitats. Please note that these images are extracted from scanned page im
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