Laura Erickson's For the Birds

(Recording of a Connecticut Warbler)

That’s the song of the Connecticut Warbler, also known as the bog black-throat, swamp warbler, and tamarack warbler. This Northland specialty summers in a few places in northern Wisconsin, most notably on a stretch of Highway “A” near Solon Springs, and in quite a few tamarack bogs in Northern Minnesota. It’s much more abundant in the western Canada, where it nests in dry, brushy openings of poplar-aspen stands.

The Connecticut Warbler is a shy and elusive bird, but quite pleasing to look at when it gives you half a chance. It’s big for a warbler—almost six inches long, weighing about 1/2 to 3/4 of an ounce—and has a solid yellow underside, solid brownish- gray back and wings, and a gray hood with a conspicuous white eye-ring. Its yellow undertail coverts are extremely long. This helps distinguish it from the similar Mourning Warbler, which occasionally shows a complete eye-ring in spite of what some of the field guides may say.

Alexander Wilson discovered the Connecticut Warbler in Connecticut in 1812 during autumn migration. But it took over 70 years before a Connecticut Warbler nest was discovered, in Manitoba. This warbler is closely related to the Mourning Warbler, Kentucky Warbler, and MacGillivray’s Warbler. The genus name, Oporornis, comes from the Latin for bird of autumn, and sure enough, these birds are found in New England more often in fall than any other season. That’s because they migrate along a different path in spring than in fall. In spring they return from South America across the Caribbean to the Appalachians, across to the Mississippi Valley, and from there to their breeding grounds in the north central states and Canada. In fall they migrate east and follow the Atlantic coast all the way down to South America.

Unlike many warblers that spend their time at tree top level, the Connecticut Warbler spends much of its life on or near the ground. It doesn’t hop—it walks—on long pink legs, bobbing its head and holding its tail up, as it forages on the ground and low branches for insects and spiders in the cracks and crevices of tree bark. It builds its nest on the ground, too. But because it’s secretive, and because not many people spend their lives tramping through bogs to study nesting Connecticut Warblers, not a whole lot is known about its nesting habits.

The Connecticut Warbler conjures up images of lots of other warblers. It looks like a Mourning Warbler, walks like an Ovenbird, flies like a thrush, and sings like both an Ovenbird and a Yellowthroat. One of its songs is often described as “beecher beecher beecher,” a little like the song of the Ovenbird except that it doesn’t rise in pitch or inflection. Another song is translated “whip-pity-whip-pity-whip,” and sounds a little like a yellowthroat.

(Recording of a Connecticut Warbler)

There are over 700 species of birds in North America, and over 400 of them have been seen in Minnesota and Wisconsin. The Connecticut Warbler may be just another one of the many birds most people in our states aren’t even aware of, but the world is a fuller, richer place because it exists.

(Recording of a Connecticut Warbler)

This is Laura Erickson, and this program has been “For the Birds.”