Merlin

Bell's Vireo Identification

The Four Keys to ID

  • Size & Shape

    A diminutive songbird with a slim build and a slender, somewhat long tail. Its bill is small for a vireo, but still thicker and more hooked than a warbler’s.

    Relative Size

    Larger than a kinglet, smaller than a Red-eyed Vireo.

    Relative Sizesparrow or smallersparrow-sized or smaller
    Measurements
    • Both Sexes
      • Length: 4.5-4.9 in (11.5-12.5 cm)
      • Weight: 0.3-0.3 oz (7.4-9.8 g)
      • Wingspan: 6.7-7.5 in (17-19 cm)

Regional Differences

Birds nesting in the Midwest to Colorado and central Texas (subspecies bellii) are the most brightly colored, with greenish backs and yellowish sides and flanks. At the other end of the species’ range, in southern California and adjacent Mexico, the tiny Least Bell’s Vireo (listed as endangered) is grayish above and pale below. Two subspecies that occur in between (from eastern California to far western Texas) are intermediate between bellii and pusillus in appearance.