We have a lot of Bluebirds coming to our feeders this year. We keep them supplied with meal worms which they seem to love. We only have one house which is home to the nest below.

I thought this was a male, based on the plumage but apparently not.

Only the female incubates the eggs. The male does not participate in the incubation of the eggs. The male protects the territory and brings food to the female while she is incubating the eggs. The female takes breaks to feed and poop in the morning hours and throughout the day. — Bluebirds Nests and Eggs: All you Need to Know