I'm also big on animal behavior and definitely am looking into graduate programs where I can focus on this. I've done research throughout my undergraduate education in zoo settings, but would like to get more into doing fieldwork.
I'm at Canisius College and will be graduating in May (can't come soon enough!), but they have an amazing BS in Animal Behavior, Ecology, and Conservation. I know you already have a BA, but there's lots of opportunity for doing research as an undergraduate. We even have someone (Christy Hoffman) who does cognitive research with canines. Canisius also offers a MSc in Anthrozoology (http://www.canisius.edu/anthrozoology/). I've really enjoyed it here and I came in wanting to be a vet, but switched to doing research because I love it so much.
The Animal Behavior Society website that Dedi referenced would be a great spot for you to start looking.