For the past month or so, a "Lawrence's" Warbler has been seen at the Kay Environmental Center in Morris County. I got to see it on Saturday. This is the rarer of the two Golden-winged Warbler x Blue-winged Warbler hybrids - "Brewster's" Warbler is the other. It was singing the bee-buzz song of a Blue-winged Warbler. Neat bird! Learn more about Cornell's Golden-winged Warbler Atlas Project which also tracks hybrids.