Sampling at night clearly improved efficiency, particularly for the "small" and "intermediate" size classes.
This is consistent with sampling recommendations for collecting age-0 and yearling walleye (McWilliams and Larscheid
1992; Serns 1982). No clear evidence was found indicating that night sampling efficiency for "small" and
"intermediate" saugeye could be improved by stratifying the sampling by season. Differences in CPUE were
inconsistent between spring and fall samples; however, precision of the fall night electrofishing samples was typically
higher than the respective samples collected in spring. In addition, stocking criteria used by ODWC's management staff
(Gilliland and Boxrucker 1995) require data be provided from previous year's stocking to receive subsequent stockings.
Therefore, fall collections of age-0 saugeye fit better into existing management protocol.
Improved capture efficiency was not evident for the "large" size class at night. No differences in CPUE were
observed in the seasonal day-night comparisons from Holdenville. However, catch rates of "large" saugeye from
Holdenville were low throughout the study indicating low population density . This may make drawing any conclusions
relative to capture efficiency of "large" individuals from the Holdenville data suspect. CPUE of "large" saugeye was
higher at night for spring samples and higher during the day in the fall from Jean Neustadt. No diel differences were
seen in the spring data from Thunderbird; however, day samples in the fall had a higher CPUE. Precise data on
"large" saugeye are needed to enhance ODWC's crappie management efforts. Saugeye are used as a tool to reduce
density of overcrowded crappie populations (Gilliland and Boxrucker 1995). It would be useful to develop correlations
between CPUE of "large" saugeye and improvements in crappie size structure and/or growth rates. However, no single
sampling strategy improving capture efficiency was evident from this study.
ODWC's management staff typically expends six units of effort or less per lake to collect data evaluating
saugeye stocking success (catch/h of age-0 saugeye in fall night electrofishing). This amount of effort appears
insufficient to provide the precision needed to meet standards suggested in the literature. Effort needs to be increased
7-fold to provide estimates +.25% of the mean. However, given current time and personnel restraints, an increase in
sampling effort of this magnitude may not be practical. Given a catch rate of 30/h, a resonable estimate for saugeye
<_ 400 mm in fall night electrofishing (Table 2), a 50% change in the mean could be detected with 7 units of effort.
This amount of effort is similar to what is currently being spent. If the objective of the sampling is to evaluate
abundance of "large" saugeye, 28 samples would be needed to detect a 50% change in the mean, given a CPUE of 5
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