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Lorertcilo Canyon Minc -Aquatic Ttchnica(ReOOrt • Fish Fish population data were collected at the stations on September 9 and 10, 1996. At each stream (lotic) station, representative 300-foot reaches were electroshocked using a Coffelt Mark-10 backpack electroshocker. As requested by the Colorado Division of Wildlife (CDOW, 1996), a one-pass/minimum population method was used. Fish were stunned, netted, identified to species, enumerated, and then released into the stream unharmed. At each pond station, fish were sampled using 30-foot seines and hand dip nets. Fish species were identified using Woodling (1985). Greystone contacted the US Fish and Wildlife Service (USFWS) for information on threatened or endangered species that may be present within the analysis area. Additionally, a fish collection permit was obtained from the Colorado Division of Wildlife. Macroinvertebrates Macroinvertebrate population data were collected at the seven stations on June 19 and 20, 1996. At the stream stations, riffle habitats were sampled by compositing three 1 ft2 samples collected using a Hess sampler. Data were collected at the pond stations by sampling 3 ft~ of substrate • using a 900-micron mesh dip net. The same area and type of substrate (microhabitat) were sampled at each station to provide quantitative comparison between stations. Additionally, each stations specific sampling location was marked and described in field notes. Contents of the samples were emptied into a standard number 30 sieve for washing and preserved with 90 percent ethyl alcohol for transport to the laboratory. The data were collected and processed using a method modified from EPA's Rapid Bioassessment Protocol, level III (EPA 1989). In the laboratory, macroinvertebrate samples were lightly rinsed in a standard number 30 sieve and transferred to a white pan. For samples with low numbers of organisms (< 100), all were removed from the sample. If samples had high numbers (> 100), only half fractions were sorted. For these samples, the appropriate coefficient was used to adjust the abundance of taxa to equal a full sample. Specimens were then preserved in alcohol for identification. Macroinvertebrates were identified to the lowest taxonomic level practical, enumerated, and recorded on laboratory bench sheets. Most organisms were identified using Merritt and Cummins (1996) and Pennak (1989). Several macroinvertebrate metrics were calculated including total abundance, species richness (number of taxa), EPT taxa, percent contribution of the dominant taxon, percent chironomidae, ratio of EPT and chironomidae abundances, Shannon diversity index, evenness, Hilsenhoff Biotic Index, and Community Tolerance Quotient. aquatic.475/December 5, 1996 2