O.B. Davis 1935 Salmon Creek, 8 mi. W Rogerson, Jwin Falls Co., Idaho, May 15. at the dam where they are nesting in a large colony. On the way back to camp I killed a young Marmot and a F? Mountain Bluebird. The condition of the latter indicated nesting. The Marmots are occupying two types of habitat here (1) the Talus slopes of huge boulders, and (2) open, rather sandy-loam talus slopes where the burrows are very conspicuous. The old ones are very wary, much more so than the younger ones and as a result we have failed to take any old specimens. The following birds were noted: Osprey - 1 lone bird flew over the dam, Prairie Falcon - nesting on the East side of the canyon, Yellow Warbler Song Sparrow Flicker. King Fisher Great Blue Heron Rock Wren Canyon Wren Sox Phoebe Lewis Woodpecker Lark Sparrow Brewer Sparrow Horned Owl Sparrow Hawk,