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