Electrofishing was conducted twice monthly from June to October 1995 on Lake Ponca Reservoir and May to October 1996 on Fort Gibson Reservoir to evaluate how temporal and environmental factors such as time of sampling, water temperature, water depth, and differing habitat types affect sampling efficiency for flathead catfish (Pylodictis olivaris). Relationships among catch data and concurrent temporal and environmental data were determined by multiple regression analysis. For each reservoir, models were generated for O/f (numbers of individuals netted/3 minutes of electrofishing), C/f (numbers of individuals netted/3 minutes of electrofishing), C/fH (numbers of individuals ≥510 mm total length netted/3 minutes of electrofishing), and C/fR. (numbers of individuals <200 mm total length netted/3 minutes of electrofishing) which were statistically significant. Sampling was most effective over areas where bank inclines were moderate to steep and bottom substrates were composed of riprap or natural rock, or where submerged structure was evident. Sampling was less effective during the later portions of the study period and as water temperatures decreased.
