Setophaga petechia
Plate — illustration to come
Summer breederNative · New Jersey

Yellow Warbler

Setophaga petechia

Parulidae

The little all-yellow warbler of willow thickets and shrubby wet edges. Males add rusty streaks to the breast and are among the brightest yellow birds anywhere. One of the most widespread breeding warblers in North America, and one of the first summer birds to leave — many depart NJ in August.

Arrives in May; departs early — most Yellow Warblers are gone from NJ by mid-August.

Identify by

How to spot one.

  • 5 inches, sleek warbler shape

  • Male: brilliant lemon-yellow overall with rusty chestnut streaks on breast

  • Female: softer greenish-yellow, less streaked

  • Dark eye stands out against pale yellow face

  • Yellow spots on tail visible in flight (unlike most warblers with white tail spots)

Voice

What it sounds like.

Sweet, upbeat 'sweet-sweet-sweet-I'm-so-sweet' — clear whistled phrases, higher and cleaner than most warblers.

Life & behavior

How it lives.

Nests in willow, dogwood, and other soft-wood shrubs near water. Often builds atop the destroyed nest of a Brown-headed Cowbird parasite — literally covering the cowbird egg with a new nest floor and re-laying. Migrates early, sometimes leaving NJ in late July.

At a glance

The spec sheet.

Status
Summer breeder
Size
4.7–5.1 inches
Present in NJ
May – August
Native to NJ
Yes
Conservation status
stable
Family
Parulidae
Diet

What it eats.

Diet often shifts dramatically between breeding season and the rest of the year — especially for insectivorous birds that pivot to native berries in fall and winter.

Summer / breeding season

  • Almost entirely insects — caterpillars, midges, aphids, beetles

  • Leafhoppers, small wasps

  • Small spiders

  • Occasional berries very late in season

Fall / winter

  • Migrates to Central America, northern South America

  • Overwintering: insects and some fruit

Plants it uses

What it needs.

Native plants that feed this bird or provide shelter. Names in hydrangea link to the plant’s Field Guide entry.

  • Willows (Salix)

    Cover / habitat

  • Native dogwoods

    Cover / habitat

  • Wet meadow shrub edges

    Cover / habitat

  • Alders, elderberry thickets

    Cover / habitat

Sources

Audubon Field Guide · All About Birds (Cornell)