BLUEBIRDS SET UP housekeeping and laid eggs to start a family before being ousted by tree swallows. The tree swallow added its eggs to the mix. Time will tell if all the young are treated equally. D. Curry photo

Dave Curry
Contributing Writer

Bluebirds and tree swallows have much in common, including habitat and food sources. oth are also cavity nesters and have the same nesting requirements. In fact, with used woodpecker holes and good birdhouses being at a premium, these same birds will struggle and fight over the best nesting sites. To the victor belongs the spoil.

The winning pair will take over the nest box and quickly remodel it to their own specifications, including evicting all sign of the previous occupants. Eggs and even young birds will be thrown out in preparation for their own family.
This year, one box has been different. Bluebirds initially set up housekeeping, built the nest and laid three eggs. Then tree swallows came along and drove off the bluebirds, taking over the nest. However, the tree swallows did not destroy the eggs. The female tree swallow merely laid two eggs and began brooding as usual.

All of this brings up many…

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