Bachman's Warbler in its habits is very much like the Parula Warbler (_Compsothlypis americana_). The resemblance is more noticeable when feeding and in search of food. The birds will then penetrate a thick bunch of leaves and go through, over and all around in the most thorough manner in their exploration after insects that appeal to their taste. They are very active, and constantly in motion. They are also quarrelsome, and resent the intrusion of other species. Frequently I have noticed them fighting away the White-eyed Vireo, and where two or more Bachman's Warblers are observed together, one is pretty sure to see them chasing and fighting among themselves. When disturbed or alarmed they are at once alert; a sharp alarm note, something like that of a Yellow-throated Warbler (_D. dominica_) is uttered, but more forcible and clear cut in its delivery. This is accompanied with a few jerks of the tail, and the bird is off to a neighboring tree. They are found alike in the trees, low bushes, and shrubbery, sometimes on or quite near the ground, and seem to prefer the heavy and more thickly grown woods to trees or bushes more in the open. Young birds are quite tame, but the adults as a rule were very shy and difficult to approach after having been once disturbed. _Voice._--The song of Bachman's warbler is of a wiry or insect-like character, and has been widely compared by many observers to the music of the worm-eating and parula warblers and the chipping sparrow. It also resembles, according to Aretas A. Saunders (MS.), one of the songs of the blue-winged warbler. Brewster (1891) says: The song is unlike that of any other species of _Helminthophila_ with which I am acquainted and most resembles the song of the Parula Warbler. It is of the same length and of nearly the same quality or tone, but less guttural and without the upward run at the end, all of its six or eight notes being given in the same key and with equal emphasis. Despite these differences it would be possible to mistake the performance, especially at a distance, for that of a Parula singing listlessly. The voice, although neither loud nor musical, is penetrating and seems to carry as far as most Warblers'. Besides the song the only note which we certainly identified was a low hissing _zee-e-eep_, very like that of the Black-and-white Creeper. Widmann (1897), observing a singing male for 8 hours, says that "the bird kept singing nearly all the time at the rate of ten times a minute with the regularity of clockwork, and its sharp, rattling notes reminded me strongly of an alarm-clock. In this regard it recalls one of the performances of Parula, whose rattle is of the same length and quality, except that it has a certain rise at the end, by which it is easily distinguished."