the orange-crowned warbler (oreothlypis celata) is a small songbird of the new world warbler family .
these birds are distinguished by their lack of wing bars , streaking on the underparts , strong face marking or bright colouring , resembling a fall tennessee warbler .
the orange patch on the crown is usually not visible .
they have olive-grey upperparts , yellowish underparts with faint streaking and a thin pointed bill .
they have a faint line over their eyes and a faint broken eye ring .
females and immatures are duller in colour than males .
western birds are yellower than eastern birds .
their breeding habitat is open shrubby areas across canada , alaska and the western united states .
the nest is a small open cup well-concealed on the ground under vegetation or low in shrubs .
the female builds the nest; both parents feed the young .
these birds migrate to the southern united states and south to central america .
they forage actively in low shrubs , flying from perch to perch , sometimes hovering .
these birds eat insects , berries and nectar .
they also enjoy peanut butter .
the song of this bird is a trill , descending in pitch and volume .
the call is a high chip .
