Are bluebirds wintering at my house?

When I saw the pair of bluebirds in my back yard over the weekend, I couldn't help but wonder if they were going to winter at my house. Their behavior was more of scouting in nature rather than just feeding. Not really being familiar with Bluebird migration, I decided to do a little research and it appears that they are not necessarily heavy migrants. In fact, it appears that Bluebirds migrate little in areas of mild climate and seem to only venture as far southward as needed in order to find abundant food.

I remember when first moving to this house, as I was watching the movers unload the truck, a couple of bluebirds were sitting on the driveway. This was early March and I can't help but wonder if these little guys I saw Saturday are the same ones that spent the spring in my woods. Maybe they will migrate southward to warmer areas once the snow hits, or maybe they'll be content foraging on the berries in the woods and supplement their diet with the seed smorgasboard at my feeders!