Passerines - itsaboutnature.net

Black-capped Chickadee in a cold Maine rain, March 30, 2014.

Here are two quality references:

http://animaldiversity.ummz.umich.edu/accounts/Parus_atricapillus/

http://www.allaboutbirds.org/guide/Black-capped_Chickadee/id/id