Warbler time is picking up in Wisconsin. During these brief weeks of warbler migration, it’s possible to identify over 20 different species in a day, each with their own songs and plumages. A favorite of mine is the Black-and-white Warbler. These birds are frequent migrants and their high contrast body creates a striking appearance. Black-and-white Warblers forage for insects among dead wood and sapsucker wells, behaving more like nuthatches in the way they cling, slide, and hop along trees. Their long hind claws and heavy legs help them to nimbly maneuver through forest habitats.
Black-and-white Warbler nest (YouTube video).
Despite living in deciduous and mixed forests with plenty of perches and foraging throughout the canopy, Black-and-white Warblers are ground-nesting birds. They build their nests near the base of trees with a composition of forest products. Leaves, bark, and pine needles make up the bulk, with moss and dried grasses for a fine lining.
They’re also good indicators of forest quality, as they typically nest in extensive and mature blocks of forest. The birds breed in the northern half of the state, with their southern range not too far out of southern Wisconsin. Birds have been documented breeding in the Northern Kettle Moraine and in the Green Lake area.
You might be able to find these warblers at Faville Grove in forested habitat, where you notice scuttling little birds with streaky black and white plumage and a downward curved bill. Having arrived, often on overnight direct flights from Central America, the Black-and-white Warbler you find might even be taking a daytime nap after a sleepless migration.
Written by Drew Harry, Faville Grove Sanctuary land steward
Cover image: A Black-and-white Warbler perches on a branch and sings (photo via Pixabay).
