The bluebird naturally nests inside tree cavities that have decayed over time. According to the Michigan Bluebird Society, due to habitat loss and the introduction of non-native species, bluebirds have a difficult time finding a natural place to nest.
Bluebird nesting boxes are especially made to give bluebirds a safe place to nest and raise their young. Where and how the nest boxes are mounted is also important to the bird's continued survival.
Mount the bluebird nesting box on a free-standing, metal, 6 to 6 1/2 ft tall pole with two pipe clamps; wood poles are not encouraged because predators can easily climb them. Lay the nesting box with the front facing down on a table or bench. Lay the pole over it, the top of the pole flush with the roof of the box. Mark the box just below the roof and just above the base where you will attach the pipe clamps. Lay the pipe clamps over the pole on the marks and mark where the holes line up. Remove the pole and clamps, drill out all four holes. Lay the pole back over the nest box. Place the pipe clamps to line up with the drilled holes. Screw in the bolts until they are through the wood. Turn the pole over so the nest box front is facing you. Open up the access door and place the nuts on the bolts, using a wrench to tighten them until secure.
Place the bluebird nest box in an open area away from trees, fences, houses or barns to avoid predators, nesting wrens or house sparrows. Turn the entrance hole of the nest box to the south or east to keep the weather from summer storms out of the box. Keep the nest box away from dense cover such as thickets or scrub to discourage hiding predators.
Bury the pole with a shovel at least 12 to 18 inches deep into the ground, leaving the nest box about 5 feet high after it is fully installed. Straighten the pole when needed; it will lean a small amount on occasion due to rain and wind.
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Place nesting boxes at least 250 to 300 feet apart if you are mounting more than one since nesting birds are territorial and will chase away other bluebirds. Mount boxes within areas of at least 1 1/2 to 2 acres of suitable habitat to enable them to find plenty of food.