2016-12-23_PERMIT FILE - C1982056A (8)

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present for sandhill crane nest establishment. These surveys did not locate any active nests even at those sites that were documented as active in early May. Several pairs and a few observations of bachelor groups of birds were •recorded, however. A total of seven distinct pairs of cranes were observed on or near the permit area. All observations of areas of suitable nesting habitat, nests, and observations of sandhill cranes were recorded and plotted on field maps and then transferred to Map 21, Locations of Sandhill Crane Nests and Nesting Habitat and Raptor Cliff- Nesting =Habitat. Locations of birds observed by John Monarch during his early May, 1984, survey are also plotted on this map. In addition to nest searches, a subjective evaluation, regarding the suitability of permit area stock ponds and drainages as crane nesting habitat, was made. This evaluation was based on a review of pertinent literature and a knowledge of nests sites preferred by cranes in northwest Colorado. Areas that were judged most suitable for crane nesting activity are noted on Map 21, Locations of Sandhill Crane Nests and Nesting habitat and Raptor Cliff - nesting Habitat. The fact that no observations of individual birds were made during the June, 1984, survey would tend to indicate that the pairs observed were either non - breeding pairs, or laying of eggs and incubation had not been initiated. During the 1984 surveys no single birds were flushed from the drainages or from around stoc ponds, and no birds were observed with young. In addition, none were observed performing a distraction display which is usually indicative of an active nest nearby (Littlefield 1968, Bieniasz 1978). Blake (1974) reported that most eggs in Colorado are laid from late May to early June. The incubation period for cranes is approximately 30 days (Drewien 1973, Blake 1974). Drewien (1973) found that cranes seldom left nests unattended once eggs were laid, and during 87 hours of observing 5 incubating pairs, he found that nests were unattended only 1.2 percent of the time. Incubation duties are shared by both birds with the female usually incubating at night and the male during the day (Blake 1974). There was some evidence that the unusually late spring and extremely high runoff in mid -May may have disrupted or delayed crane nesting activity in Twentymile Park. In Blake's (1975) studies on nesting cranes in northwest • Colorado, nesting was delayed about two weeks as a result of late, heavy snowstorms. Unusually late spring snowstorms and heavy spring runoff were documented for the general Twentymile Park region in 1984. Runoff in mid -May in Twentymile Park was so high that Fish Creek overflowed its banks and washed out a portion of County Road No. 27 near the southern edge of the permit area. Many of the smaller drainages in the permit area also showed evidence of high water, as indicated by debris piled up in the sagebrush above the drainages. High water in mid -May may explain why the nest located in early May by John Monarch could not be relocated in June. In a study of nesting cranes in Oregon, Littlefield (1968) documented one case of nest desertion as a result of flooding. It is uncertain whether re- nesting would occur after desertion due to flooding, but re- nesting following egg destruction by predators has been documented (Littlefield 1968, Drewien 1973). Three additional active: nests were located in the permit area by CDOW personnel during a helicopter survey of the general area in late June, 1984. Two nests contained two eggs and one was vacant. Locations of these nests are also plotted on Map 21, Locations of Sandhill Crane Nests and Nesting Habitat and Raptor Cliff- nesting Habitat. Unless notified by regulatory authorities, no further surveys are planned. Critical Big -Game Winter Range Overlay for Permit and Surface Disturbance Areas As a component of the Wildlife Resources Information requirement, elk and mule deer critical winter range areas, as depicted on CDOW Wildlife Information System Maps, were overlayed with the TCC Permit boundaries and proposed areas of surface disturbance. Mule deer and elk winter range, winter concentration areas, severe winter range, critical winter range, and migration routes were plotted on base maps showing the Permit boundaries and proposed surface disturbances. As discussed previously, mule deer winter habitat in the permit area is limited to the southeast portion. Critical •winter range and concentration areas occur along the southwest and southeast facing, shrub- covered slopes near Foidel Creek (Map 20, Mule Deer Biological Features). No mule deer migration routes have been identified in the area. As shown on Map 20, Mule Deer Biological Features, no new surface disturbances are proposed to occur within any mule deer critical winter range or concentration areas. An existing road at the eastern end of designated RN08 -05 2.04 -67 03/12/10