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until N was less than the number of samples already processed for each taxon. Because <br />of time and financial constraints, we never picked more than 30 samples total for each <br />habitat type and sample date. All sorted samples were preserved in 70% ETON. <br />Chironomid Identification <br />Chironomids to be identified were removed from 70% ETOH and placed in <br />distilled water for 10-15 minutes. Individual specimens were placed in hot (-800 C.) <br />10% KOH (Cranston 1982) for 5 to 15 minutes to clear (larger specimens required more <br />time to clear). After clearing, the specimens were transferred to distilled water for at <br />least five minutes. Each specimen was then placed in glycerine on a microscope slide <br />for identification. Only latter instars were identifiable. Representative specimens of each <br />genera encountered were permanently mounted. <br />Larval Chironomidae were identified to the genus level using keys in Merritt and <br />Cummins (1984), Wiederholm (1983), and Mason (1968). <br />Data Analysis <br />Confidence Intervals <br />Mean densities (#/m) and 95 % confidence limits of the four main taxa and each <br />genera in the Chironomidae were calculated for each sample site and date. Because of <br />the their contagious distribution, ninety - five percent confidence intervals for each of the <br />four main taxa were calculated using the logarithmic transformation in Elliot (1977) <br />(tables 1-4). These were than applied to the arithmetic mean (Shiozawa and Barnes <br />1975). Confidence intervals were not calculated for each genus in the Chironomidae <br />because densities of some genera were too low. <br />8