David -- I would second Greg's list -- however for Massachusetts I also like Cape Ann, where from Halibut Point and other sites on the peninsula you can see a wide variety of alcids and other goodies. Last year we saw King Eider, Dovekie, Razorbill, Black Guillemot, Glaucous Gull and other species in the late Feb. time frame. There were still some Snowy Owls at Logan as well, but your dates may be too late (?). Cheers, Gail Mackiernan