Spring migratory birds: Yellow Warbler

Yellow Warbler carrying nesting material. © C.S. Wood

Yellow Warbler
Setophaga petechia

by Christopher S. Wood
 “Sweet, sweet, sweet, ain’t I sweet!” sings the Yellow Warbler, and indeed it is sweet to hear this most vocal of warblers warming up the early spring season with song.

Also among the most common of warblers here in Connecticut, the Yellow Warbler is aptly named: it is yellow! While the male proudly displays bold chestnut stripes down his breast, the female is pure yellow tip to toe. No wingbars, no tail spots, just yellow, highlighted by a big black eye, like a round lump of coal.

Yellow Warblers are widespread across North America, regular breeders in every state except a few of those on the Gulf Coast.

But this species is amazingly diverse by itself, in fact the most morphologically diverse of all the warblers. No fewer than 37 subspecies are recognized, including one found on the Galapagos Islands.

Here in Connecticut, we are most familiar with the S. p. aestiva subspecies; the male of this subspecies shows the boldest chestnut breast streaking of the group.

Yellow Warbler photographed at White Memorial Little Pond Litchfield, May 2018. © C.S. Wood

Typically favoring wet thickets, usually with willows, as well as early successional areas, their bright gold flashes through the bushes and trees are hard to miss as they go about building nests and raising young. Nests are usually located from 1 – 10 feet above the ground and are built exclusively by the female, although the male eventually helps with feeding the nestlings.

Like many warbler species, Yellows are a prime target of the nest parasite Brown-headed Cowbird. But they have evolved an unusual defense: the female rebuilds her nest right over the cowbird eggs even as many as five times.

The males’ “sweet, sweet, sweet” song is instantly recognizable, but like many warbler species, there may be confusing variations. And distinguishing the song from that of the Chestnut-sided Warbler, which is often found in close proximity, can get difficult.

Easy to find, easy to see, easy to identify, and very entertaining, Yellow Warblers are a welcome neighbor and a valuable case study in warbler behavior.

Christopher S. Wood, of Woodbury, has been contributing bird articles and photographs to Connecticut Audubon since 2017. Read his Daily Bird and other contributions here.