Laura Erickson's For the Birds

(Recording from “Wizard of Oz” ‘Somewhere over the rainbow bluebirds fly; Birds fly over the rainbow–Why then, oh why can’t I?’)

The bluebird has been a symbol of happiness for centuries. Early ornithologists wrote often of its pleasing, gentle nature, although grasshoppers, katydids, crickets, beetles, and other insects consider it a vicious killer. Point of view is very important in the natural world.

The Eastern Bluebird’s plumage is about as patriotic as a bird gets–it has a red breast, white belly, and bright blue back. It was never abundant, but was fairly common from colonial times into the early 1800’s. When European settlers cleared the eastern forest, that helped bluebirds–their habitat is open areas like farms and orchards. They nest in tree cavities–usually abandoned woodpecker holes. But to offset the increased habitat, settlers introduced the House Sparrow and European Starling. These species, with their generalized diet and high adaptability, quickly multiplied to number in the hundreds of millions, and they aggressively competed with bluebirds for nesting cavities. If that wasn’t bad enough, pesticides, especially DDT, decimated bluebirds from much of their range. Few modern city-dwelling children ever see or hear a wild bluebird–they’ve been robbed of their birthright.

(Recording of an Eastern Bluebird)

Fortunately, in rural areas bluebird houses put up by individuals, DNR non-game wildlife funds, and bluebird trail organizations are helping to insure that the Eastern Bluebird won’t disappear. Bluebird numbers have gone up in Minnesota and Wisconsin in the past few years. Last fall I saw quite a few migrating over Hawk Ridge. Bluebirds and Robins are two of the only songbirds that migrate by day in spring and fall. The most likely areas in the Northland to spot migrants in spring would be along the South Shore of Lake Superior, and along the Mississippi around Grand Rapids. I’m eagerly awaiting the first reports of this harbinger of spring from listeners.

If you live in town or in a wooded area, you can set out bluebird nest boxes, but you won’t get bluebirds. Instead, you’ll probably get Tree Swallows, which are equally lovely and eat huge quantities of mosquitoes.

If you live in an open area and want to attract bluebirds, but haven’t set out nest boxes yet, you’d better get crackin’. Make sure the entrance hole is exactly 1 1/2 inches in diameter. Anything less than that is too narrow for a pregnant bluebird to squeeze through, and anything more than an inch and a half is wide enough to let a starling through. Hardware and gardening stores often sell them ready-made, or you can get plans from the Wisconsin or Minnesota DNR. You’ll have the best luck if you set out nest boxes in pairs. Tree Swallows take over a lot of bluebird nests, but they are very territorial and aggressive toward their own species. If you have two boxes near each other, a pair of swallows may move into one, but they’ll drive all other swallows from the other box, leaving it for the bluebirds. Tree Swallows are protected by state and federal laws, so you aren’t entitled to throw out babies or eggs from your bluebird boxes. Anyway, the happiest bluebird trails accommodate both species. (“If happy little bluebirds fly beyond the rainbow why oh why can’t I?”)

This is Laura Erickson, and this program has been “For the Birds.”