2012-09-07_PERMIT FILE - M2012018 (2)

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4.2 Federal Threatened and Endangered Wildlife Species The U.S. Fish and Wildlife Service (2012) lists ten federally protected threatened and endangered wildlife species (or candidate for listing) that may occur within Boulder County or that may be negatively affected by water depletions within the County. Table 1 lists these species, briefly characterizes their preferred habitats, and discusses their potential for occurrence on the project site. There is no suitable habitat for any of these species at the project site, and the project would not result in any water depletions to the South Platte River beyond those for which water rights are already allocated. Therefore, the proposed project would not have direct or indirect impacts on federally protected wildlife species. There is no designated critical habitat within or near the project site. 4.3 State of Colorado Threatened, Endangered and Sensitive Species The CPW (2012) state list of threatened, endangered and sensitive species was reviewed (Table 2). The project site contains potential habitat for one species, the northern leopard frog (Rana pipiens). No additional discussion of the remainder of the species listed in Table 2 will occur in this document. 4.3.1 Northern Leopard Frog, Rana pipiens The northern leopard frog is distributed throughout Colorado in most riparian habitats from an elevation of below 3,500 feet on the plains of the northeastern corner of the state to over 11,000 feet in the San Juan Mountains in the southwestern corner (Hammerson 1999). Although formerly abundant throughout its range, the northern leopard frog has become rare or been extirpated from many areas, especially high elevation populations due to changes in habitat conditions (Hammerson 1999). Northern leopard frogs are widespread across North America, inhabiting the banks and shallow portions of marshes, ponds, lakes, reservoirs, beaver ponds, streams and other bodies of permanent water, especially those having rooted aquatic vegetation (Stebbins 1966, Hammerson 1999). Winter months are spent in a state of torpor at the bottom of occupied bodies of water (Hammerson 1999). After hibernation, leopard frogs become active in April or May. Breeding occurs in the shallow, non - flowing portions of permanent water bodies and seasonally flooded areas adjacent to permanent pools. Breeding pools typically support fairly clear water with vegetation and algal mats. Eggs are attached to submerged vegetation. Metamorphosis occurs during the first summer, with tadpoles transforming in August or September, depending on elevation. The diet consists of insects, spiders, grubs, and larvae. They avoid overgrazed habitats. Formerly abundant, northern leopard frog populations have decreased in recent years. Evidence of population declines in the mountainous regions of Colorado have been documented by Corn and Fogleman (1984) and Hammerson (1999); although, these have been primarily restricted to the Front Range of the Rocky Mountains. Hammerson (1999) identified climatic variation (i.e., flooding and drought), as reasons for local shifts in populations. In low elevation habitats, the introduced bullfrog (Rana catesbeiana) has been identified as a threat, as has the introduction of predatory game fishes to ponds and other habitats where leopard frogs were formerly common. Other threats include the human induced alteration of wetlands through filling dredging or increases in overall water depth. Flood control activities and other water diversion efforts have also impacted leopard frog populations (Hammerson 1999). Although the CPW recognizes the species as a species of concern, no mapping of species occurrence is available through either the CPW or the Natural Diversity Information Source (NDIS). A petition to list the western United States population of the northern leopard frog as a threatened or endangered species was filed with the U.S. Department of the Interior on June 5, 2006. On 30 June 2009 4