If you have nestboxes on your property, fall is a good time to clean them out and make any necessary repairs. It’s especially important to make sure the roof isn’t leaking, and that the entrance hole has not been enlarged, which could allow predators and starlings access. If the hole has been chewed up by squirrels or woodpeckers, you can either put a metal hole guard over it, or cover it with a wooden block with a 1.5” diameter hole drilled in it.
House Sparrow nests are typically messy and bulky wtih feathers and trash. House Sparrows are non-native, aggressive predators, and should not be allowed to use a nestbox.
It’s also a good time to put up a new nestbox. In the fall, birds check out boxes they might use next year. Be sure you buy or make a box specifically designed for bluebirds. A good bluebird nestbox:
- is made of unpainted, untreated 3/4"1" wood or PVC
- has a solid roof with a 2-5” overhang
- a round 1 1/2 " diameter hole or 1.375" x 2.250" oval hole
- no perch
- has ventilation holes
- is deep enough so predators can't reach in
- has a door that opens for cleaning and regular monitoring.
Since there are a lot of farms and bird feeders in rural areas, there are also a lot of House Sparrows. House Sparrows are a non-native, aggressive species that will peck the eggs of native birds like Bluebirds, Tree Swallows and Chickadees. House Sparrows will toss nestlings out of the box, and kill adult birds. They are so prolific that one pair of breeding birds could theoretically multiply into more than 1,000 birds over a 5 year period. Thus House Sparrows should not be allowed to breed in nestboxes.