Vireo gilvus
The Warbling Vireo may be the most common of the Rocky Mountain vireos, but you must still search a long time before you will spot one. The often-repeated song of this bird, with its oscillating quality, delights anyone listening; the phrases finish on an upbeat as if asking a question of the wilds. In contrast to the bird's velvety voice, however, is its dull plumage. Lacking any splashy field marks, the Warbling Vireo is exceedingly difficult to spot, unless the bird suddenly moves from one leaf-hidden stage to another. Once the voice of the Warbling Vireo is learned, auditory encounters will soon abound. Searching the treetops for inconspicuous birds may literally be 'a pain in the neck,' but the satisfaction in visually confirming this bird's identity is exceptionally rewarding. |
I.D.: Sexes similar: white eyebrow; no wing bars; olive-gray upperparts; greenish flanks, light underparts; gray crown. Size: L 51/2 in. (14 cm). Range: common migrant and breeder throughout the Rockies. Habitat: open deciduous forests and shrubby avalanche slopes in the montane. Nesting: in a horizontal fork in a deciduous tree or shrub; hanging, basket-like cup nest is made of grass, roots, plant down, spider's silk and a few feathers; pair incubates 4 eggs for 12 days. Feeding: gleans foliage for invertebrates; occasionally hovers and plucks insects from vegetation. Voice: Male: musical warble: I love you I love you Ma'am! or iggly wiggly iggly piggly iggly eeek! Female: occasionally sings from the nest. Similar Species: Red-eyed Vireo: black eye line extends to the bill; blue-gray crown. Tennessee Warbler: gray head; olive back. Orange-crowned Warbler: smaller; darker underparts. |
