2017-02-03_PERMIT FILE - C1980004A (11)

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Biological Assessment for DMG Permit Renewals McClane Canyon & Munger Canyon Mines ~; 1998; Andrews and Righter 1992). Breeding birds occur in low densities throughout their range (Kingery 1998). Numbers of wintering birds across the state are higher than breeding numbers, and are concentrated around prairie dog colonies or areas with significant populations of ground squirrels, cottontails, or jackrabbits (Andrews and Righter 1992). Populations and reproductive success of ferruginous hawks may fluctuate with prey populations (Smith et al. 1981; Woffinden and Murphy 1977). Ferruginous hawks nest in open landscapes in isolated junipers or less commonly, on the ground (Righter et al. 2004), on rock outcrops, utility poles, or windmills (Andrews and Righter 1992). Common roosts are hilltops near prairie dog colonies, cottonwoods, and utility poles (Righter et al. 2004). Threats to ferruginous hawks include conversion of grasslands and shrubsteppe rangelands to croplands and urban developments, and widespread extermination of prairie dog colonies and other rodents (Kingery 1998; Bechard et al. 1995). A few records of ferruginous hawk in Garfield County have been documented by CNHP, but none of the occurrences were in the Howard Canyon USGS quadrangle (CNHP 2005). This species is unlikely to nest in the relatively narrow canyons of McClane or Munger, although it potentially hunts for rodents in the sagebrush or semi-desert shrub canyon bottoms of the assessment areas, especially during winter. Human presence and mine activities may influence ferruginous hawk foraging patterns in the immediate area, but are unlikely to produce measurable effects on the species. Yellow-billed cuckoo (C). Probably never common in western Colorado (Bailey and Niedrach 1965), this bird is now considered an extremely rare summer resident and nearly extirpated in western Colorado (Kingery 1998; Righter et al. 2004). The species does not winter in Colorado. Reasons for decline of the yellow-billed cuckoo throughout the western U.S. have been attributed to destruction of its preferred riparian habitat due to agricultural conversions, flood control projects, and urbanization (Hughes 1999). In some parts of its breeding range, pesticide use may have affected the yellow-billed cuckoo's prey base-injurious pest insects such as tent caterpillars, which tend to occur in cyclic outbreaks (Hughes 1999; Ryser 1985). Only one confirmed nesting occurrence was recorded in western Colorado (the Yampa River near Hayden) during Colorado BBA surveys from 1987 through 1994 (Kingery 1998). CNHP (2005) lists one record of yellow-billed cuckoo in La Plata County. Since the 1990, only one to two yellow-billed cuckoo observations, and no nesting reports, have occurred annually in western Colorado, mostly from the Uncompahgre River and Grand valleys (Righter et al. 2004). The preferred habitat of yellow-billed cuckoo is low elevation river corridors. They nest in old- growth cottonwood forests or woodlands with dense, scrubby understories of willows or other riparian shrubs (Kingery 1998; Hughes 1999). Studies in Calrfomia indicate this species may need extensive stands of riparian forest for nesting success (Righter et al. 2004 citing Gaines and Laymon 1984). Limited habitat in and adjacent to the permitted areas of surface disturbance (approximately 2 acres of perennial and 4 acres of ephemeral riparian corridor) is only marginally suitable for this species due to sparseness of cottonwoods, the small stature of existing cottonwoods, and lack of significant cottonwood canopy. Given the availability of more suitable nesting habitat in the Grand Valley some 20 miles south, and given the low abundance of this species in western Colorado and the low likelihood of it selecting the marginal habitat in the assessment areas, the proposed actions are not likely to cause measurable effects to yellow-billed cuckoo. 5.2 Fishes The upper Colorado River Basin is home to 12 native fish species, four of which are listed as endangered under the ESA: bon ail (USFWS 1980), Colorado oikeminnow (USFWS 1967), March 27, 2006 10 Rare Earth Science, LLC