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<br />Tolerant Chironomidae - The sub-families Chironominae, Orthocladiinae, and <br />Tanypodinae are tolerant of fine sediment and organic enrichment. <br /> <br />Simuliidae - Abundant in all lotic waters, but excessively high numbers (>40% <br />total abundance) may indicate nutrient enrichment. <br /> <br />Tolerant amphipods - Common in springs and downstream of dams, numerous amphipods <br />in other stream types may indicate nutrient enrichment. <br /> <br />Tolerant snails - Most pulmonate snails are tolerant of warm water and fine sediment. <br /> <br />Oligochaeta - Highly tolerant of fine sediment. <br /> <br />Leeches - Tolerant of fine sediment and organic enrichment. <br /> <br />Voltinism <br />Voltinism refers to life cycle length. Taxa requiring more than one year to <br />complete their life cycle are more dependent on stable conditions than short <br />lived taxa. A community with very few taxa with life cycles longer than eight <br />months might indicate instability or a recent pollution event. Taxa were <br />classified as being multivoltine, (multiple generations per year), univoltine, <br />(a single generation per year), or semivoltine, (life cycles last more than one <br />year). Classification was based on published and unpublished sources. <br />