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Bluebird houses with pole are an easy and inexpensive way to invite bluebirds into your backyard. You can build one yourself using simple plans provided by the North American Bluebird Society, or purchase a prefabricated house that meets research-approved specifications. In addition to a well-sized entrance hole and proper ventilation holes, look for a birdhouse that includes a hinged or removable panel on the roof or side for monitoring and end-of-season cleaning. It should also have a plastic mesh ladder below the entrance for adults and fledgli