. . .we'd detect a lot more! On my bicycle commute to CMBO-CRE this morning I heard at least 11 Blackpoll Warblers, the only definite migrant species I detected.
Blackpolls are one of our most common migrant warblers, and as warblers go they are relatively unusual in that they migrate north in large numbers along the eastern seaboard (starting by coming through Florida for most of them). They also tend to keep coming through in numbers later in May than other species, a product of their huge breeding range which extends even above the Arctic Circle in Western Canada and Alaska. But even given those facts, their far-reaching and distinctive song and the frequency with which they sing makes them one of the most detectable spring migrants we have, whether on bike, on foot, or out the car window.