[6][3] The summer male black-and-white warbler is boldly streaked in black and white, and the bird has been described as a flying humbug.

[3][4] The genus name comes from the Ancient Greek mnion, meaning "seaweed", and tillo, "to pluck".

It is typically found in deciduous forest in its breeding range, but becomes more of a habitat generalist in the non-breeding season.

[3]The black-and-white warbler occupies a broad niche, and is found in a variety of habitats.

During migration, this species prefers forest to other land cover types and is frequently found in riparian areas.

In its wintering habitat, it can be found in a variety of land cover types, from mangroves to wet, dry, and cloud forest.

[4][15] The IUCN classifies the black-and-white warbler as Least Concern due to its large range and population size.

[9] Habitat loss and degradation, especially forest fragmentation, are the main factors contributing to the species' decline.

[16][17] Pesticides such as fenitrothion and phosphamidon have contributed to the species' decline in the 1970s,[18] and others such as chlorinated hydrocarbons may continue to have an effect.

[2][6] This bird feeds on insects and spiders, and, unlike other warblers, forages like a nuthatch, moving up and down tree trunks and along branches.

It forages on tree trunks and limbs to feed on insects below the bark's surface.

[8] Its short legs and long hind toe are adaptations to this foraging method.

[4] Its diet is composed of insects and other arthropods, including lepidopteran larvae, beetles, ants, and spiders.

[20] During migration, the black-and-white warbler sometimes joins mixed flocks to feed.

The young fledge after 8 to 12 days, and stay around the nest while they improve their flight ability.

[21] Black-and-white warbler nests are sometimes parasitized by the brown-headed cowbird (Molothrus ater).