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declines have been caused by over-fishing, timber harvesting, livestock <br />grazing, irrigation, and other development along or near streams. <br />If this race occurs in the vicinity of the West Elk Mine, it will likely be <br />hybrid stock as there are no isolated headwaters close by. Any development <br />will have no effect on the pure or nearly pure stock. <br />Great Basin Silverspot Butterfly, Speyeria nokomis nokomis <br />The Great Basin Silverspot Butterfly is known only from Utah and southwest <br />Colorado where it inhabits natural seeps where there is a constant flow of <br />water (Ferris b Fisher 1971). The presence of Viola nephrophylla, the larval <br />food plant, is also critical. The adults fly from mid July to early September <br />and the larvae are restricted to their violet food plant. The two main <br />Colorado colonies that are known are in seeps over a substrate of granite or <br />blowsand. The three colonies known from Colorado are in Mesa, Montrose, and <br />La Plata counties. A stray female vas collected in Delta County at Rogers <br />Hess near Hotchkiss at 5850 feet elevation. <br />A few seeps have been noted around the West Elk Mine, but none of these <br />appear to have a constant flow of water. The substrate in the area is not <br />conducive to constant flow. Viola nephrophylla has not been observed in the <br />vicinity. The chance of this butterfly occurring in the area of the mine is <br />close to zero. <br />Brandegee Milkvetch, Astragalus brandegei <br />The Brandegee Milkvetch is known from Colorado, New Mexico, Arizona, and <br />Utah. "It is very inconspicuous, easily overlooked..., and ,.. may therefore <br />be commoner than is generally supposed" (Barneby 1964). Habitats listed by <br />Barneby (1964) include, "Arid, sandy or gravelly clay banks, flats and stony <br />meadows, mostly in pinon-juniper woodland, sometimes !n oak brush, rarely in <br />yucca-grassland, most commonly on sandstone, occasionally on granitic or <br />basaltic bedrock, 5400-8650 feet." Other habitats where it has been collected <br />include Indian ricegrass, blue grams, snakeweed, fringed sagebrush community; <br />grass-shrub community; disturbed open pine; salt desert shrub community; and <br />sandstone with Pinus aristata and Artemisia frigida. Elevational limits have <br />been extended up to 8800 feet. It flowers from May through July. In <br />Colorado, it has been found in Conejos, Fremont, Mineral, and Gunnison <br />counties. With such a wide range of habitats and broad elevational range, it <br />is likely that the plants are indeed more common than supposed. They could be <br />expected just about anyplace in the region. There are at least 25 different <br />locations now known. It is unlikely that the species is truly threatened. <br />The closest known population to the West Elk Mine is near Gunnison, the <br />northern-most known locality in Colorado and about 35 miles southeast of the <br />mine. Development around the mine is not likely to affect the species. <br />Colorado Desert Parsley, Lomatium concinnum <br />The Colorado Desert Parsley is known only from Colorado but has been found <br />in at least 15 locations in Delta, Ouray, and Montrose counties. It flowers <br />in May and grows on Mancos shale/clay nearly always associated with saltbush. <br />Elevations range from 5000 to 7200 feet (unconfirmed report of 4270 to 7300 <br />feet). A small area of Mancos Shale outcrops near the west end of mining <br />activity, but that area is densely vegetated with oak, chokecherry, and <br />serviceberry and has no saltbush. A survey there in late April did not turn <br />up any Lomatium. Any mining development would likely have no impact on this <br />species. <br />3 <br />