Laserfiche WebLink
algae and plant debris (Kwan and Morrison 1974). <br />Corkum (1990) investigated streams associated with different land use types in <br />southwestern Ontario and found densities of 50/m2 in "forested" sites 480/m2 in "mixed" <br />sites and 5,300/m2 in "farmland" sites. Adamek and Sukop (1992) found maximum <br />desities of only 1/m2 on overflooded meadows in Czechoslovakia. In Lake Norman, <br />North Carolina, Bowen (1983) reported a mean larval cerotpogonid density of 767/m2. <br />In our study, mean chironomid densities reached their peak in the August river <br />channel sample (13,026/m2) - much higher than those sites mentioned above. In their <br />study of the Green River, Grabowski and Hiebert (1989) failed to give any ceratopogonid <br />densities but did conclude that ceratopogonids were more abundant in river channel <br />samples than in backwaters. Our study supports this conclusion. The average densities <br />for the river channel samples were 3,608/m2 and 13,026/m2 compared to 96/m2 and <br />461/m2 for the backwater. The absence of ceratopogonid larvae from the ephemeral side <br />channel and seasonally inundated wetland June and July samples remains unexplained. <br />Chironomidae <br />Chironomidae are one of the most important taxa present in aquatic systems <br />worldwide. Study of a small geographical area has reported over 140 different species. <br />(Douglas and Murray 1980). Because of this high diversity, they are important as <br />indicators of environmental condition (Wingard and Olive 1989) and as a food source for <br />fish (Brown et al. 1980, Winkel and Davids 1987, Grabowski and Hiebert 1989), <br />waterfowl (Titmus and Baddock 1980), and other migratory birds (Bowman 1980). <br />Despite the role that chironomids play in aquatic systems, many studies classify them <br />16