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<br />6 mm light traps, three 2 mm or 4 mm light traps, and four trammel nets over a two day period. <br />Each sampling day two fyke nets, tall minnow traps and short minnow traps were baited with <br />commercial puppy chow. Traps receiving bait were assigned randomly. All four trammel nets <br />were set in a single morning. Nets were set for two hours. Habitat depth and vegetation types <br />(emergent vegetation, open water [with or without submergent vegetation] and flooded terrestrial <br />vegetation) were recorded for nets set in 1996. Catch rates from gear, by vegetation category and <br />depth, were tested with a randomized complete block anova design. Data from both short and <br />tall clover-shaped minnow traps were combined for analysis (they were identical in all features <br />but height). The GLM method of anova was used to test for differences in dates (block), <br />vegetation or depth (treatment) and interaction between block and treatment as provided by SAS <br />(SAS, 1987). Three depth intervals were tested within minnow traps (<0.5 m, 0.51 m - 1.5 m, <br />and> 1.5 m) and two within fyke net sets, <0.75 m and > 0.76 m, respectively (fyke nets could <br />not fish satisfactorily in depths less than 0.5 m). The partial sum of squares option was used in <br />defining significance. The four most abundant species captured in each gear type were tested <br />individually. <br /> <br />Results <br />Differences in gear types used among years to monitor relative abundance did not allow <br />direct comparison in catch per unit of effort among years. However, several trends in fish <br />capture rates and composition occurred within years. Gill and trammel nets were designed to <br />monitor the presence and abundance of larger fish. Capture data from these nets were dominated <br />by carp Cyprinus carpio through all three years of the study (Figure 5, Appendices 4,5, and 6). <br />In both 1994 and 1996 a general increase in fish caught per net set occurred over time and was <br />largely attributed to vulnerability of age-O carp to nets later in the summer. Length frequency <br />data indicated that in the week of 24- 31 August, 1994 age-O carp ranged in total length from 110 <br />to 150 mm (Figure 6) and became vulnerable to gill nets (Figure 5). Fish capture in gill nets rose <br />from an average of21.9 fish/net to 106.1 fish/net following the week of24-31 August and was <br />due almost exclusively to increased catch of age-O carp. <br />Capture rates of trammel nets in 1995 and 1996 were substantially less than 1994 and can <br />be attributed to the shorter set time. No increase in catch/net trend was observed in 1995, <br />although carp continued to dominate the catch composition. In 1996 a small trend in the increase <br />in fish caught/net occurred. Growth rates of age-O carp in 1996 were similar to that in 1994 and <br />age-O ranging up to 90 mm by 10 July. A small increase in number of catch/net was observed on <br />9 July, afterward sampling was suspended to begin draining. Catch rates offish in trammel nets <br />showed little increase through 1995. Although the composition was also dominated by carp, <br />length frequency data indicated 1995 age-O carp showed slower growth. <br />Seines and minnow traps were used to monitor the composition and abundance of smaller <br />and younger fish in the wetland. In 1994 shoreline seining was dominated by carp, fathead <br />minnows Pimephales promelas and red shiners Cyprinella lutrensis (Figure 7). Greater numbers <br />of fish were collected earlier in June and July. Fathead minnows were collected throughout the <br />year whereas carp increased in size and were not captured as frequently after 13 July. Red <br />shiners were abundant in mid July and decreased into late August. Length frequency data <br />indicated that fathead minnow, red shiners and green sunfish Lepomis cyanellus reproduced in <br />Old Charley Wash. Age-O fish fathead minnow and red shiner were present by at least 28 July <br /> <br />18 <br />