Rocky-Mountain Creeper 497 
Genus CERTHIA. 
Characters of the family ; only one species in the United States, 
separated into several geographical races. 
Rocky-Mountain Creeper. Certhia familiaris montana. 
A.0.U. Checklist no 726—Colorado Records—Ridgway 73, p. 180; 
Trippe 74, p. 230; Henshaw 75, p. 177; Drew 81, p. 88; 85, p. 15; 
Allen & Brewster 83, p. 154; Beckham 87, p. 123; Morrison 88, p. 72; 
Kellogg 90, p. 89 ; Lowe 94, p. 270 ; Cooke 97, pp. 121, 222 ; Henderson 
03, p. 108; 09, p. 241; Gilman 07, p. 195; Rockwell 08, p. 178. 
Description.—Adult—General colour above dusky brown, streaked 
with white ; rump and upper tail-coverts rufous, with slaty bases and 
white spots to the feathers; wings dusky with white spots on the 
coverts and remiges ; 4 more or less clearly defined white eyebrow ; 
below almost pure white, very faintly tinged with buffy posteriorly ; 
iris brown, bill dusky brown, paler at the base of the lower mandible, 
legs brownish. Length 4:90; wing 2-5; tail 2-6; culmen -52 ; tarsus -59. 
The sexes are alike and the young closely resemble the adults. 
Distribution.—The Rocky Mountain region from Alaska to New 
Mexico and Arizona; on migration to south-eastern California and 
perhaps to northern Mexico, but generally a resident throughout the 
year. In Colorado the Creeper is found all the year round, chiefly 
between 7,000 and 9,000 feet in winter, and from 9,000 feet to timber 
line in summer, but it may be met with almost anywhere from the 
foothills to timber line at almost any season. The following are 
breeding records: Estes Park at timber line (Kellogg), Boulder co., 
9,000 to 11,000 feet (Gale), Idaho Springs, at timber line (Trippe), 
near Fort Garland (Henshaw), San Juan co. (Drew), and La Plata co. 
(Morrison) ; it has been taken in El Paso co. in February, May and 
December (Aiken coll.), and in Boulder co. in winter (Henderson), 
and is considered only as an occasional visitor, chiefly in winter, at 
Grand Junction (Rockwell). 
Habits.—This bird derives its name from its habit 
of creeping about the trunks and larger branches of trees, 
and in this its stiff tail and sharp claws greatly assist 
it; so closely does it harmonize with the rough bark 
over which it glides that it is often extremely difficult 
to detect it; it has a thin, sharp, long drawn-out cry 
which generally betrays its presence. It feeds on small 
insects, their eggs and larve, for which it searches 
diligently under the interstices of the bark. 
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