If you page through the warbler section of Pieplow's eastern guide, you will quickly see that the Black-and-White Warbler has the highest voice among southeastern warblers, with American Redstart a close second. (Several of the northeastern "sprucewood" warblers have high voices, an interesting pattern.) But, this one is easy to hear, thanks to eBird's technology. He appears to be giving us a mid-morning recitation of his dawnsong, which uses his "second catergory" repertoire (eastern Peiplow, page 385). Notice the insertion of very brief chip notes in front of each song. Many songbirds jazz up their dawnsongs in this way. If nothing else, it adds an urgent quality to the performance.
Black-and-White Warblers are nuthatch "wannabes," i.e., their foraging behavior and the morphology that permits it, are convergent on the nuthatch (Family Sittidae) habit of creeping around on tree trunks. Neither uses the tail as a prop, and so they depart in this regard from woodpeckers (Family Picidae), who, one could say, are the masters of trunk foraging in the bird world. Both the nuthatches and this warbler from the family Parulidae are not the only songbirds (Order Passeriformes) to converge on niches previously staked out by nonpasserine families. Swallows, shrikes, sunbirds, honeycreepers, treecreepers, and woodcreepers all come to mind.