ASH-THROATED FLYCATCHER 133 



ish brown, uper tail-coverts strongly tinged with cinnamon-rufous, 

 outer webs of remiges mostly buffy cinnamon-rufous, other wing- 

 markings tinged with cinnamon-bufF, and yellow of under parts much 

 paler (yellowish white)." 



Apparently, young birds have a postjuvenal molt in August and 

 September, involving the contour plumage but not the wings and tail ; 

 this produces a first winter body plumage like that of the adult ; the 

 remiges and rectrices are evidently molted the following spring and 

 summer. 



Practically all the June and July adults that I have seen are in 

 much worn plumage; and October birds all seem to be in fresh 

 plumage. This indicates a complete molt during August and Sep- 

 tember; I have seen one adult, taken September 21, that is in fresh 

 body plumage but is molting both wings and tail. There is probably 

 a very limited prenuptial molt, about the head and throat, in young 

 and perhaps in old birds. 



Food. — Professor Beal (1910), reporting on the contents of 80 

 stomachs of the ash-throated flycatcher, says : 



Though an orchard bird, it seldom eats any cultivated fruit, but confines its 

 diet largely to insects, most of which are either injurious or neutral. * * * 

 Animal food amounts to 92 percent and vegetable to 8 percent for the season. 

 * * * One stomach taken in September held 44 percent of elderberries, which 

 is exceptional. * * * Of the animal food, beetles, almost entirely of harmful 

 species, amount to 5 percent. * * * Bees, wasps, and a few ants (Hymenop- 

 tera) amount to 27 percent. * * * Bugs (Hemiptera) aggregate about 20 

 percent of the food of the ash-throat, which is in the largest showing for that 

 order of insects yet found in the food of any flycatcher. * ♦ * While many 

 of these are taken upon tlie wing, probably some are picked from plants. 

 One bird was seen on a mustard plant feeding upon the plant lice, which com- 

 pletely infested the plant. One stomach was entirely filled with tree hoppers 

 and two with cicadas. * * * Flies (Diptera) amount to about 14 percent 

 and were eaten in nearly every month. * * * Caterpillars were found in 

 20 stomachs and moths in 7. Together they amount to 19 percent of the food. 

 This shows that caterpillars are a favorite article of food with this bird, and 

 proves that it does not take all of its food on the wing. While no stomach 

 was entirely filled with caterpillars, one contained nothing but moths. Grass- 

 hoppers formed about 5 percent of the food, and were mostly taken In May, 

 June, and July. One stomach contained nothing else. As they do not often come 

 within reach of flycatchers, these insects must be especially sought for. Various 

 other insects and spiders amount to a little more than 3 percent. ♦ * * 



Vegetable food was found in 9 stomachs. Of these, 5 contained remains of 

 elderberries ; 2, bits of other small fruit ; and 2, skins which might have been 

 tho.se of cultivated varieties. 



Bendire (1895) adds to the vegetable food the berries of a species 

 of mistletoe that grows abundantly in southern Arizona; and Dr. 

 Beebe (1905) saw it devouring many varieties of small fleshy fruits, 

 when insects were scarce. Mrs. Bailey (1928) says that "five taken 



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