They are distinct from eastern bluebirds and mountain bluebirds, although there are areas where the distributions of all three species overlap. Western bluebirds require open habitat with grass between scattered trees.
Western bluebirds are year-round residents that winter in territorial family groups.
They are joined by immigrant females and often mate with these females the next spring. During the winter, the birds feed primarily on mistletoe berries. They move onto breeding territories in February - March. Western bluebird pairs mate for life. Although a small percentage of pairs divorce, most western bluebird pairs mate for life.