Worm-eating Warbler

Helmitheros vermivorum

Early Spring Date: April 17
Late Spring Date: May 24
Best Dates to See in Spring: April 26 - May 9

Spring: Worm-eating Warblers are regular visitors to Monticello Park, but never in significant numbers. They usually pass through early, and the most likely time to find one is around the end of April and the first week in May. Worm-eating Warblers nest in the Washington metro area, but not at Monticello. Their preferred nesting habitat is deciduous and mixed woodlands, often near water.

Fall: An average of only one or two Worm-eating Warblers pass through Monticello each fall.

Where to See Them in the Park

Worm-eating Warblers forage in the mid-story and understory. They sometimes go into the stream for a quick bath or drink. You are more likely to hear one than to see one.

Physical Description

Worm-eating Warbler
Worm-eating Warbler - Photo by William Higgins

Worm-eating Warblers are mostly olive with a buffy head. The best fieldmarks are the broad black stripes on the head. Adult males, adult females, and second-year birds all look similar.

Worm-eating Warbler
Worm-eating Warbler - Photo by Ashley Bradford

Worm-eating Warbler
Worm-eating Warbler - Photo by William Higgins

Worm-eating Warblers have a long bill that is dark on top and pale underneath.


The song of the Worm-eating Warbler is a dry, insect-like trill.

Hear the song of the Worm-eating Warbler.


Worm-eating Warbler
Worm-eating Warbler - Photo by Edward Eder

Worm-eating Warblers do not eat earthworms. Their name comes from their fondness for the caterpillars of butterflies and moths. A lot of other warbler and songbird species are "worm-eating" in the same sense. The widespread use of pesticides to kill various types of caterpillars could have serious long-term consequences for these species. Worm-eating Warblers are "dead-custer feeders" — they often forage for food in hanging clusters of dead foliage. The bird in the above photo is eating a daddy long legs.

Origin of Names

Common Names: Worm-eating is a translation of the scientific species name. The New World Warblers were named for their similar appearance to European warblers, to whom they are not related. Most of the New World warblers do not warble (sing continuously with notes that change frequently).
Genus Name: Helmitheros means "worm hunter".
Species Name: Vermivorum means "worm eating".

Worm-eating Warbler video footage

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