HERMIT WARBLER 325 



two narrow, white wing bars, faintly tinged with pale yellow; the 

 breasts and sides are pale "hair brown" to "light grayish olive" ; and 

 the rest of the under parts are yellowish white. A young bird in 

 fresh plumage, collected July 1, is probably in full juvenal plumage; 

 its body plumage is similar to that of the nestlings, but there is some 

 yellow on the forehead and throat, and the sides of the head and neck 

 are decidedly yellow ; however, this may be a bird that has assumed 

 its first winter plumage at an unusually early date. 



In first winter plumage, young birds of both sexes are much like the 

 adult female at that season, mainly grayish olive-green above, with 

 black streaks concealed or absent; forehead, sides of the head, and chin 

 pale yellow; and the rest of the under parts buffy white, the sides 

 browner. The broad, white tips of the lesser wing coverts have a 

 black shaft streak or wedge, apparently characteristic of this plumage. 

 There is probably a prenuptial molt involving much of the head and 

 body plumage and the wing coverts, but the dull juvenal wings are 

 retained until the next molt. 



The complete postnuptial molt occurs in July and August. The 

 fall plumages of both sexes are like the spring plumages, but the clear 

 blacks and yellows are largely concealed by olive above and by buffy 

 below. 



Food. — The only item I can find on the food of the hermit warbler 

 is the following short statement by Bowles (1906) : "Their food con- 

 sists of small spiders, caterpillars, tiny beetles, and flying insects which 

 they dart out and capture in a manner worthy of that peer of flycatch- 

 ers the Audubon warbler." 



Behavior.— The most marked trait of the hermit warbler is its fond- 

 ness for the tree tops, spending much of its time in the tops of the 

 tallest firs, often 200 feet or more above the ground, where it is very 

 active and not easy to follow. But it builds its nest at lower levels, 

 and often comes down to forage in the lower branches, in smaller trees 

 and even in the underbrush, where it is not particularly shy and can 

 be easily approached. It is a close sitter while incubating; Bowles 

 had to lift one off its nest. 



A hermit warbler watched by Miss Margaret W. Wythe, in Yosemite 

 Valley, "was foraging in the upper parts of the trees and never 

 came to the lower branches. Starting from near the trunk of a pine 

 it would work out to the tip of one branch before going to another. 

 Its demeanor while foraging was much more deliberate than that of 

 any of the other warblers" (Grinnell and Storer, 1924). 



Voice.— Rathhun (MS.) writes : "The song is quite strong, can be 

 heard a considerable distance, and when given in full consists of five 

 or six notes. The first note, rather faint, rises and then falls, with a 

 slight accent at its close ; if one is quite close to the singer, the note 



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