Pennsylvania Bluebird Basics

Why did the bluebird population decrease?

The introduction of non-native species such as English sparrows and European starlings has influenced bluebird populations in Pennsylvania. The European transplants began to dominate the nesting cavities bluebirds preferred. DDT and other harmful pesticides hampered reproduction until they were banned nationally in ’70s. And Pennsylvania’s open spaces (preferred bluebird habitat) slowly, but steadily, were reclaimed by trees, or worse, buildings. The bluebird’s perfect world was slipping away.

How can I help bluebirds?

You can help provide a home for bluebirds by placing nest boxes in your backyard and creating bluebird nest box trails. Nest boxes provide additional cavities bluebirds. You can find plans for building bluebird boxes as well as pre-made bluebird boxes on the Game Commission website.

Where should I place a bluebird box?

A box is best placed on a post – not a tree trunk – four to six feet off the ground in direct sunlight. Preferred locations are open backyards, meadows, near fencerows or agricultural fields, and around cemeteries or athletic fields. Boxes placed too close to houses and other buildings, waterways and wetlands, or forested and brushy areas will attract nesting competitors and predators.

Nest box competitors

Of course, it should be pointed out that a bluebird nest box used by any species other than a house sparrow – starlings can’t access the entrance of a properly-constructed bluebird nest box – is still a box that’s serving wildlife and helping to fill a habitat deficiency. If helping bluebirds is your objective, then place or relocate your nest box to an area where there will be limited nesting competition and predator problems, and where bluebirds are more apt to find it. If you’re reusing a box, remove old nesting materials from inside before hanging it. Otherwise, recognize its worth to other wildlife and place it where it’ll do some good.

-Excerpts from “Bluebird Basics” by Joe Kosack

Joe Kosack’s full article on Bluebird Basics is available on the Game Commission website.

Photo by Joy Mellott