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Biological Assessment for DMG Permit Renewals McClave Canyon & Munger Canyon Mines <br />•~ from the introduced bullfrog and stocking of non-native predatory fishes (Hammerson 1999). <br />Their status is unknown in the assessment areas, and affected habitat in the assessment areas <br />is limited to bridge crossings of the East Salt Creek riparian corridor. Potential impacts from the <br />proposed actions are limited to habitat fragmentation from pre-existing surface disturbance and <br />accidental roadkill. Sediment ponds at the mine sites may be providing new habitat for the <br />species. Given the limited areas of pre-existing surface disturbance and the limited amount of <br />suitable habitat, the proposed actions are not likely to jeopardize the continued existence of the <br />northern leopard frog. <br />5.4 Reptiles <br />Nofederally-listed reptiles are affected by the proposed actions <br />Lonanose leopard lizard (S, SC). A fairly uncommon lizard with patchy distribution in extreme <br />westem Colorado. Habitat is generally flat or gently sloping arid shrublands with large a <br />percentage of bare ground beneath the shrub canopy. The species is known in Colorado from <br />elevations below 5,200 feet, and from the north side of the Grand Valley from clay soils in <br />Atriplex spp. shrublands near arroyos and semi-permanent streams (Hammerson 1999). <br />Threats are thought to incude semi-0esert shrubland habitat conversions to irrigated agricultural <br />lands or residential use in the Grand Valley (Hammerson 1999). One documented occurrence of <br />longnose leopard lizard exists within 2 miles southwest of the Munger access road intersection <br />with Highway 139. This occurrence was recorded below 5,200 feet in Mancos Shale soils <br />(CNHP 2005). The assessment areas represent peripheral range and mostly unsuitable habitat <br />for longnose leopard lizard. Less than approximately 10 percent (about 3 acres) of the <br />combined permitted areas of surface disturbance represent suitable habitat, all of which is <br />higher in elevation than the published upper elevation range limit of the species. Occupancy in <br />the assessment areas is expected to be low to none due to habitat characteristics and naturally <br />scattered distribution of the species; therefore, the proposed actions are not likely to jeopardize <br />the continued existence of the longnose leopard lizard. <br />Milk snake (S). The milk snake is a colorful banded constrictor occupying a wide variety of <br />habitats in Colorado, including shortgrass prairie, shrubby hillsides, sandhills, canyons, pinyon- <br />juniperwoodlands, ponderosa pine woodlands, and arid river valleys. Their distribution in the <br />state roughly reflects that of human distribution, but this may be an artifact of uneven <br />observation efforts (Hammerson 1999). The population status of the milk snake in the <br />assessment areas is unknown. Only one documented occurrence of milk snake has been <br />recorded in Garfield County, in the Colorado River valley (Hammerson 1999). Milk snakes prey <br />opportunistically on a variety of small vertebrates, reptile eggs, and bird eggs. They hibernate <br />underground between October and April. Known threats include collecting for pet trade; <br />moderate alteration to habitat typical of rural human communities seems to be well-tolerated <br />(Hammerson 1999). Impacts to this snake in the assessment area are probably limited to <br />habitat bisection by roads and accidental road kill, although disturbance of hibemacula may be <br />possible from subsidence events. Given the limited areas of pre-existing surface disturbance <br />and level of operational activities at the mine sites, the proposed actions are not likely to cause <br />measurable impacts on the milk snake. <br />Midoet-faded rattlesnake (S, SC). The midget-faded rattlesnake is a sutrspecies of the westem <br />rattlesnake known only from Mesa, Delta, and Garfield counties (Hammerson 1999). It occupies <br />a broad range of terrestrial habitats, except perennially wet areas and high mountains. The <br />entirety of the assessment areas represent suitable habitat for this snake. Rodent burrows, rock <br />crevices, woodpiles, woody snags, and brushy vegetation are used for cover during the active <br />season-roughly May through October or November. Winter dens in northwestern Colorado <br />` March 27. 2006 12 Rare Earth Science, LL( <br />