Blue-winged WarblerVermivora cyanoptera
The simple buzzy song of the Blue-winged Warbler is often heard in brushy overgrown fields and thickets in the East during the summer. Although the bird is not especially shy, it can be a challenge to observe as it forages actively in the dense brush. In recent decades this species has been expanding its range northward, encroaching on the territory of its close relative, the Golden-winged Warbler. The two species often interbreed.