When Do You Clean Out Bluebird Houses?

Cleaning Out Predators

• Monitor the bluebird house weekly to keep it free of sparrow or other undesirable bird nests. Bluebird nests typically are 1 to 4 inches tall and made of pine needles or fine grasses. The eggs are powder blue or white and usually four to six eggs are present. Sparrows build tall nests of coarse grass and paper or bits of trash. Generally, there are five to seven cream-colored eggs that have brown markings. Remove nests that are not from bluebirds, because undesirable birds like sparrows aggressively seize bluebird nests. House sparrows destroy eggs and kill the young baby birds and adult bluebirds. Removal of active nests is illegal, according to the Migratory Bird Treaty Act of 1918.

Cleaning Blowfly Larvae

• Monitor the bluebird nest each week to prevent blowfly larvae from invading the baby bluebirds. The larvae weaken and even kill the baby birds. If you see evidence of infestation, pick up the baby birds gently and remove any larvae. Look underneath the baby bird's wing to get rid of larvae that may be hidden. Clean out the infested nest and discard all materials. Gather fine grass clippings and form a new similar-looking nest and replace the baby birds quickly to prevent them getting too cool.

Cleaning the Birdhouse

• It is important to clean out the birdhouse after bluebird chicks have left the nest or after a failure to nest. This increases the chances of re-nesting if the birdhouse is free of debris, bacteria, mold and nesting materials. Empty the birdhouse of any debris. Soak the house in a solution of one part chlorine bleach to nine parts water. This kills any bacteria. Use old toothbrushes or a bottle brush to get into the crevices. A soapy solution of a mild dishwashing detergent and warm water is all that is necessary to sanitize wooden birdhouses. Rinse the birdhouse well and allow it to dry thoroughly.

Attracting Bluebirds

• Make the entry hole on your bluebird house approximately 1 1/2 inches in diameter. Do not install a perch. It is unnecessary for the bluebirds and may attract undesirable birds. Mount the birdhouse on a smooth metal pole. This helps prevent predators, such as raccoons, snakes and cats.