Animal Life in the Yosemite
NPS Arrowhead logo

THE BIRDS

CEDAR WAXWING. Bombycilla cedrorum Vieillot

Field characters.—Slightly larger than Junco; head crested; plumage soft appearing; tail small; sexes alike. General color of plumage grayish brown; belly yellowish; chin, bill, and streak through eye, black; tail tipped with yellow; under tail coverts whitish. Flight swift, undulating, in a course usually low over or among trees. Voice: A series of rather faint, high pitched, hissing notes.

Occurrence.—Sparing visitant in fall, winter and spring on both slopes of Sierra Nevada. Stations and dates of record: Snelling, May 26, 1915 (5 individuals); Smith Creek, 6 miles east of Coulterville, January 31, 1917, and December 7, 1915; El Portal, October 7, 1914 (one); Yosemite Valley, September 28, 1920 (small flock); Warren Fork of Leevining Creek, September 27, 1915 (12); Mono Lake Post Office, May 24, 1916 (one). Seen usually in close flocks, in or near berry producing shrubs or trees.

The Cedar Waxwing is one of the few species of birds which wander about over the country erratically, appearing as a winter visitant in numbers in a given locality for one or more years and then being almost or entirely absent from that locality for a like period. Its movements are probably governed by food supply; yet it seems curious that, patronizing as it does a wide variety of trees and shrubs, it should not readily find one or another of these growths offering in any one locality sufficient food for the season. The Cedar Waxwing appears in winter chiefly in the valleys and lower foothills; but Mr. Donald D. McLean recorded the species at Smith Creek (east of Coulterville) on January 31, 1917, and he says further that it has been seen commonly there in winter and spring of some years. A small flock was seen feeding on mistletoe berries in the top of a tall incense cedar in Yosemite Valley on September 28, 1920, by Mr. C. W. Michael (MS). The birds noted at Snelling and Mono Lake Post Office in late May were probably late migrants bound northward; for the species is not known to nest in the Sierra Nevada.

It is the usual habit of 'Cedar Birds' to travel in flocks of 25 to 50 individuals. A flock will visit some heavily fruiting plant; the individual birds will gorge themselves to satiety, and then rest on perches during the action of their digestive processes, until, presently, they may indulge in further feeding. Mistletoe berries are an important article of their diet in the hill country. Many of the berries eaten by Cedar Birds are retained only long enough to enable the digestive juices to dissolve the outer layers. Then the resistant or indigestible central portion, which in the berry of the pepper tree has a hot and disagreeable taste, is disgorged.

When feeding, the birds are very active, clinging to slender twigs so as to reach the berries, sometimes hanging inverted in chickadee-fashion, twisting, fluttering, making short flights to regain a lost perch, and occasionally uttering their shrill hissing notes. If disturbed while feeding, they fly off swiftly, in close formation and in undulating course, low over the trees, and utter their unique notes in chorus as they go.



<<< PREVIOUS CONTENTS NEXT >>>

Animal Life in the Yosemite
©1924, University of California Press
Museum of Vertebrate Zoology

grinnell/birds154.htm — 19-Jan-2006