As we talked about in a PREVIOUS POST, winter causes many birds, including the American robin, to decrease their territoriality, and flock together.
Sometimes, I am really, really bad at identifying birds. Below are two pictures of birds that I think I have identified correctly, but am not positive. The first I think is a picture of a pair of chipping sparrows (Spizella passerina).
Robbins, C. S., Bruun, B., & Zim, H. S. (1983). Birds of North America. New York: Golden Press.
Stokes, D. W., & Stokes, L. Q. (2010). The Stokes field guide to the birds of North America. New York: Little, Brown.