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<br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br /> <br />EXECUTIVE SUMMARY <br /> <br />A 5 member survey team, representing U.S. Geological Survey, National Park Service, and Utah <br />Division of Wildlife Resources surveyed the invertebrate, fish, and amphibian communities of <br />the lower 80 km reach of the Escalante River. The objective was to begin gathering baseline <br />biological information on the more remote sections of this unique watershed. The survey ran <br />through June 22 to June 26, 1998. A total of eight sample sites were examined, four located <br />between Harris Wash and Fence Canyon (10 km) and four between Fool's Canyon and Coyote <br />Gulch. Sample sites were distanced, approximately 3 Ian apart. <br /> <br />A total of 475 macroinvertebrates representing 19 taxa were collected, 116 from the upper reach <br />and 359 from the lower reach. The dominant families were Chironomidae, Hydrosychidae, <br />Simuliidae, and Tricorythidae. Diversity was fairly constant throughout the study area as was the <br />MHBI, which summarizes the overall pollution tolerances of the taxa collected. <br /> <br />Over 300 fish were collected representing 3 native and 8 nonnative species. This survey adds <br />two additional species, striped bass (Morone saxatilis) and yellow bullhead (Ictalurus natalis), to <br />the 14 species previously reported. The mainstem river between Harris Wash and Fence Canyon <br />is remarkably endemic, consisting of round tail chub (Gila robusta), speckled dace (Rhinichthys <br />osculus), and flannelmouth sucker (Catostomus latipinnis). Of the 88 fish collected from the <br />mainstem, 87 (99%) were native. Downstream sites were dominated by non-natives which <br />constituted 89% of our collections. Red shiner were quite abundant making up 85% of the fish <br />collected downstream of Fools Canyon. Permanent pools foundin side canyons were dominated <br />by green sunfish and fathead minnows. It appears the mainstem native community is relatively <br />stable, since species composition has changed little during the past 25 years. <br /> <br />Amphibian inventories were conducted at 13 stations, 7 in the upper and 6 in the lower reach. <br />Five amphibian species have been documented in the study area, including the Great Basin <br />spadefoot (Spea intermontanus), canyon treefrog (Hyla arenicolor), Northern leopard frog (Rana <br />pipiens), red-spotted toad (Bufo punctatus), and woodhouse toad (Bufo woodhousei). Surveys <br />encountered 15 adults, 200 juveniles, 1,975 tadpoles, and 3 egg strands, all being Woodhouse <br />toads. The absence of the other species may be attributed to the timing of the sampling. <br /> <br />This open-file report provides a discription of one field trip. It was not intended to represent an <br />extensive survey effort nor a complete analysis of field data. This report represents a repository <br />of field data, observations and discriptions of ecological conditions in June 1998, and provides <br />some recommendations for resource managers. <br /> <br />IV <br />