2020-10-27_PERMIT FILE - C1981035 (20)

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Biological Assessment Federal Coal Lease Modification(COC-62920)and Federal Mine Permit(CO-0106A)Revision and Renewal Distribution and Status The species has been extirpated from most of its historic range and is now found only in the Rio Grande from below Cochiti Dam to the headwaters of Elephant Butte Reservoir in New Mexico. The silvery minnow is extirpated from the Pecos River and from the Rio Grande downstream of Elephant Butte Reservoir and upstream of Cochiti Reservoir(Bestgen and Platania 1991). Designated Critical Habitat The USFWS designated critical habitat for the Rio Grande silvery minnow in 2003 (USFWS 2003). Critical habitat includes portions of the Middle Rio Grande River and the Jemez River through Socorro, Valencia, Bernalillo, and Sandoval counties, New Mexico. There are four primary constituent elements of critical habitat specific to Rio Grande silvery minnow, as described below: 1. A hydrologic regime that provides sufficient flowing water with low to moderate currents capable of forming and maintaining a diversity of aquatic habitats such as, but not limited to, the following: backwaters, shallow side channels, pools, eddies, and runs of varying depth and velocity—all of which are necessary for each of the particular silvery minnow life-history stages in appropriate seasons; 2. The presence of low-velocity habitat within unimpounded stretches of flowing water of sufficient length that provide a variety of habitats with a wide range of depth and velocities; 3. Substrates of predominately sand or silt; and 4. Water of sufficient quality to maintain natural, daily, and seasonally variable water temperatures in the approximate range between 350F and 85°F, and reduce degraded water conditions (decreased dissolved oxygen, increased pH, etc.) (USFWS 2003). Threats Throughout much of its historic range, the decline of the Rio Grande silvery minnow is attributed primarily to destruction and modification of its habitat due to dewatering and diversion of water, water impoundment, and modification of the river(channelization). Competition and predation by introduced non-native species, water quality degradation, and other factors also have contributed to its decline (USFWS 2010). 5.1.2 Greenback Cutthroat Trout Greenback cutthroat trout have typically occupied relatively steep, cold-water streams and rivers and accessible high-mountain lakes throughout the South Platte and Arkansas river basins (Young 2009). Though presumed to be extinct by 1937, several wild populations of what were thought to be greenback cutthroat trout were discovered in the South Platte and Arkansas river basins starting in the late 1950s. These discoveries launched an aggressive conservation July 2017 22