YELLOW-THROATED VIREO 283 



Lepidoptera, butterflies and moths in their various stages, consti- 

 tuted the largest item, more than 42 percent of the whole, of which 

 caterpillars amounted to more than half of this, 23.1 percent. Most 

 of the adults were moths, 19.35 percent. Heiniptera, true bugs, occu- 

 pied second place, stink bugs amounting to 15.5 percent, and the re- 

 maining 7.62 percent including such forms as assassin bugs, scale 

 insects, and leafhoppers. "Beetles of all kinds, making up 12.9 percent 

 of the yearly food, stand third in the diet. Ladybird beetles, usually 

 plentifully found in the stomachs of vireos, in this species amount to 

 less than 1 percent of the total." The injurious beetles eaten include 

 weevils, wood-boring forms (Buprestidae and Cerambycidae) , the 

 plant-feeding Elateridae, dung beetles and leaf chafers (Scarabaei- 

 dae), leaf beetles (Chrysomelidae), and ladybird beetles (Coccinelli- 

 dae). Diptera make up 7.36 percent, Hymenoptera 5.07 percent, and 

 other insects 4.92 percent. No honey bees were identified, but there 

 were some sawflies and ichneumon-flies. The other insects eaten 

 include grasshoppers, crickets, locusts, dragonflies, cicadas, mosquitoes, 

 midges, and plant lice. 



Behavior. — On its nest the yellow-throated vireo, like the blue- 

 headed vireo, is a close and steadfast sitter, allowing close approach 

 and even handling ; it cannot easilj^ be driven from its nest and must 

 often be removed forcibly, sometimes with difficulty. It seems quite 

 fearless in the presence of humans; Francis Orcutt (1928) tells of 

 one that came and fed a young bird several times while he held the 

 little one in his hand, perching on his thumb or finger. It is, however, 

 sometimes quite aggressive when its nest is approached, attempting 

 to drive away the intruder by scolding and threatening to attack him. 

 Dr. Brewer (Baird, Brewer, and Eidgwa}'^, 1874) writes: 



They are somewhat confiding and trustful of man, are readily approached, 

 and soon become so well acquainted with those among whom they have a home 

 as to fearlessly come to the windows of the house in pursuit of spiders or flies, 

 and even to enter them. In the latter case they cannot readily make their exit, 

 and soon lose their self-possession, beating their heads against the walls and 

 ceiling In vain attempts to get out, unless caught and released. In one instance 

 a young bird, that had entered my barn-chamber, became so entangled in cob- 

 webs, around his wings and feet, as to be unable to escape again. When taken 

 in the hand, and his meshes one by one picked out from about his feet and quills, 

 he was very docile, made no resistance or outcry, nor any attempt to escape, until 

 he was entirely freed from his bonds, although it required some time and care 

 to accomplish it. When entirely freed from these clogs, and permitted to go, 

 he flew away very deliberately to a short distance, and occupied himself with 

 dressing his disordered plumage. 



Voice. — Aretas A. Saunders has given me the following elaborate 

 account of the song and call notes of this vireo: "The song of the 

 yellow-throated vireo is long continued, consisting of short phrases 

 separated by pauses. In this respect it is like the songs of the blue- 

 headed and red-eyed vireos, but there are a number of differences, 



