You mean the bird that goes, “insert my best whistling here.” “It’s the White Throated Sparrow.” According to the Cornell Institute it’s song is, “A pretty, thin whistle that sounds like Oh-sweet-canada-canada or Old-Sam-Peabody-Peabody. The whistles are even but typically move slightly up or down in pitch by the second or third note. The whole song lasts about 4 seconds. White-throated Sparrows sing often during the breeding season, even in the middle of the day, and on their winter range as well. Males of both forms sing, and so does the “white-striped” female. “Tan-striped” females sing very rarely.”
You can find some variations of the tune they sing on this blog sorry I can’t figure out how to just add it to my website. You can also hear the sound on the Minnesota DNR bird page. If you’ve been to the Boundary Waters then there’s no doubt you’ve heard the sound of the White Throated Sparrow.