NORTHERN PINE WARBLER 411 



brown. Wings and tail deep olive-brown the secondaries and rectrices 

 with greenish gray edgings, the tertiaries and wing coverts edged with 

 drab; two dull white wing bands. Below, olive-gray washed with 

 drab on the throat and sides and indistinctly mottled with deeper 

 gray. Orbital ring white." A partial postjuvenal molt, involving 

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

 or the tail, begins late in July in the north, and produces for first 

 winter birds an entirely different plumage, in which the sexes are 

 first distinguishable. Of the young male, Dr. Dwight says : "Above 

 bright olive-green veiled with drab-gray edgings, the upper tail coverts 

 grayer. Wing coverts black, edged with greenish olive-gray; two 

 white wing bands. Below, including superciliary stripe and orbital 

 ring bright lemon-yellow, fading to dull white on abdomen and cris- 

 sum, veiled with whitish edgings, the flanks washed with drab-gi-ay, 

 a few concealed dusky streaks on the sides of the breast. Lores and 

 postocular spot dusky." The first winter plumage of the female "is 

 much browner than that of the male, being olive-brown above and 

 pale wood brown below with scarcely a tinge of yellow." 



The first nuptial plumage is "acquired by wear which is excessive, 

 birds becoming greener above and greener yellow below by loss of the 

 edgings, the breast streaks being also exposed." The first nuptial 

 plumage of the female is grayer than in the fall, easily distinguishable 

 from that of the male. Old and young birds are now practically alike, 

 except for the duller juvenal wings and tail. 



A complete postnuptial molt in July and August produces the adult 

 winter plumages of the two sexes, much like those of the first winter, 

 but yellower, with more streaking and less veiling, in the male and 

 also yellower in the female, the latter resembling the first winter male. 

 Nuptial plumages are acquired by wear, as in young birds. 



Food. — A. H. Howell (1932) reports that the examination of seven 

 stomachs of pine warblers, some of which might have been of the 

 Florida subspecies, all taken in Florida, "showed the food to consist 

 largely of insects and spiders, with small quantities of vegetable 

 debris. The insects taken included gi^asshoppers, grouse locusts, 

 moths and their larvae, beetles, ants and other Hymenoptera, bugs, 

 flies, and scale insects." It has been known to eat the cotton boll 

 weevil, aphids, and the eggs and larvae of other insects. As it ob- 

 tains most of its food on the pine trees, it is evidently very useful in 

 ridding these trees of the various insect pests that injure them, seeking 

 them in the crevices in the bark of trunks and branches and, in the 

 clusters of needles and under the scales of cones. 



It is an expert fly-catcher, but in winter, when insects are not so 

 easily obtained, and probably at other times to some extent, it feeds 

 largely on vegetable food, mainly the seeds of the various pines, but 

 also on wild fruits and berries, such as those of dogwood, wild grapes, 



