_Weasel, longtail_—Occasionally seen above treeline on Trail Ridge at Rock Cabins and Rock Cut; and at woodpiles in lower meadows. _Gnawing Mammals_ _Beaver_—Workings along Glacier Creek in Glacier Basin, in Hallowell Park, Moraine Park, Lower Hidden Valley, Grand Lake Valley. Seen early or late in the day. _Chipmunks_ (Colorado and Least)—Common everywhere, especially on Trail Ridge and on Gem Lake Trail. _Cottontail_—Only at lower elevations. Fairly common in Hallowell Park, Moraine Park, and Beaver Meadows. _Hare, snowshoe_—Occasional in spruce-fir forests and down to about 8,500 feet. Common around Phantom Valley Ranch. _Jackrabbit, whitetail_—Uncommon; above treeline on Trail Ridge. _Marmot, yellowbelly_—Common everywhere in rocky country, especially on lower Cub Lake Trail. _Mouse, deer_—Common everywhere at night; often seen running across road or heard in cabins and tents. _Mouse, western jumping_—Uncommon; in dense vegetation along streams. _Muskrat_—Often seen at twilight in Sheep Lake and nearby ponds; also in old beaver ponds along lower Cub Lake Trail. _Pika_—Fairly common in rockpiles above 9,500 feet, as at Rock Cut on Trail Ridge, along trail on Flattop, above Bear Lake Lodge, and at Longs Peak Boulder Field. _Pocket gopher, northern_—Piled diggings evident in most grassland, especially in high country. _Porcupine_—Common in ponderosa and lodgepole forests; often encountered on Bear Lake and Grand Lake Highways at night. Dens in rocks. _Squirrel, golden-mantled ground_—Common everywhere in rocky country, especially on Trail Ridge, at Bear Lake, and along lower Cub Lake Trail. _Squirrel, Richardson ground_—Common everywhere in grassland at middle elevations, especially Moraine Park and Estes parkland. _Squirrel, spruce_—Fairly common in spruce-fir forest, especially around Bierstadt Lake, Cub Lake, Brinwood to Pool, upper Hidden Valley, Wild Basin, and lower Lawn Lake Trail. _Squirrel, tassel-eared_—Occasional in ponderosa pines at Sheep Lake, Tuxedo Park, and Gem Lake Trail. [Illustration: Cougar.] APPENDIX B—GUIDE TO BIRD OBSERVATION (_Courtesy, Dr. R. G. Beidleman, Colorado College_) SPECIES AREAS (see key below) 1 2 3 4 5 6 7 8 9 10