PACIFIC AUDUBON'S WARBLER 265 



leave the nest, which occurred when they were two weeks old, the male forgot 

 to sing and became a veritable family drudge with the brood ever at his heels 

 clamoring for food. * * * ijjjg ^^^y ^jiose young hud hatched so early were 

 very friendly, feeding them without much fear while I sat within three or four 

 feet of the nest and on a level with it. They usually came with nothing to be 

 seen in their beaks, but the insect food they had gleaned and carried in their 

 own throats was regurgitated into the throats of the young. When the latter 

 were five days old the mother bird, for the first time, brought an insect large 

 enough to be seen, and crammed it into the open bill of one of the nestlings, 

 and from that time on most of the food brought was eaten by the young while 

 fresh. 



The general opinion seems to be that two broods are often, perhaps 

 usually, raised in a season. The young birds are the first to leave 

 their mountain resorts, probably driven out by their parents, and are 

 the first to appear in the lowlands. 



Plmnages. — The plumages and molts of Audubon's warbler are 

 similar in sequence to those of the myrtle warbler; in juvenal and 

 first fall plumages the two species are almost indistinguishable, though 

 there is always more white in the tail feathers of the western bird, 

 in which the white spot usually reaches the fourth feather even in 

 young birds. In any plumage the white areas in the tail of Audubon's 

 warbler occupy two more feathers on each side of the tail than in the 

 myrtle warbler. 



The juvenal Audubon's warbler is brown above, streaked with 

 black and white, and white below, streaked with black; the sexes are 

 alike. This plumage is worn but a short time; Dr. Grinnell (1908) 

 says that it "is of very short duration, not more than fifteen days, I 

 should say"; and Swarth (1926) says that is "worn but a few weeks. 

 Tail and wing have scarcely attained full length when the first winter 

 plumage begins to appear, and by the time the birds are drifting 

 back into the lowlands in September the last vestige of the juvenal 

 plumage is gone." This postjuvenal molt involves all the contour 

 plumage and the wing coverts, but not the rest of the wings or the 

 tail. 



In the first winter plumage there is but slight difference between 

 the sexes, the female being somewhat duller than the male and often 

 with little or no yellow on the throat. In both sexes the plumage 

 is browner throughout, the yellow areas are paler and less pronounced, 

 the black streaks are less prominent, and the white areas in the tail 

 are more restricted than in fall adults. Swarth continues : "All winter 

 long these drab-colored birds pervade the lowlands, conspicuous only 

 through force of numbers. Then, the latter part of March, comes 

 the prenuptial molt that brings such marked changes to the male. 

 This molt is extensive, far more so than with most of our birds in 

 the spring, since it includes all of the plumage except flight- feathers 



