Lily's "Bell's Vireo"
When it is glimpsed in low brushy thickets of the Midwest or Southwest, this bird looks totally nondescript. When it is heard, however, it is easy to recognize, singing a jumbled clinking song, as if it had a mouthful of marbles. The species has become less common in recent years in many parts of its range, partly because it is a frequent victim of cowbird parasitism; many pairs of Bell's Vireos succeed in raising only cowbirds, not their own young.
-National Audubon Society
Lily's "Bell's Vireo"
When it is glimpsed in low brushy thickets of the Midwest or Southwest, this bird looks totally nondescript. When it is heard, however, it is easy to recognize, singing a jumbled clinking song, as if it had a mouthful of marbles. The species has become less common in recent years in many parts of its range, partly because it is a frequent victim of cowbird parasitism; many pairs of Bell's Vireos succeed in raising only cowbirds, not their own young.
-National Audubon Society