According to my calendar, the eastern bluebirds should return to the Northland any day now. I’ve observed singing male eastern bluebirds as early as mid-March, but not this year! Nevertheless, it shouldn’t be long until the sweet melodies of male bluebird songsters will be drifting sweetly from fields and backyards everywhere. Oh, wonderful springtime is here once again.
A prize for the eyes for any birdwatcher, bluebirds are one of the most “watchable” avian friends and are members of a very pleasant group of birds. Mention bluebirds in a room where wildlife enthusiasts — particularly birds — abound, and you’re certain to make plenty of friends.
Bluebirds are thrushes that belong to an avian family comprised of such species as American robin, Swainson’s thrush and veery. Our species of bluebird here in Minnesota is the eastern. Two others, the western and mountain bluebirds, are typically observed throughout western United States. Even so, all three species of bluebirds’ ranges overlap and occasional hybridization occurs. Mountain bluebirds are rarely seen in Minnesota, but do in fact show up and surprise a number of birders every year. Some people have even reported mountain bluebirds nesting in the state.
Eastern bluebirds are about seven inches long from tail tip to beak tip. The eloquently dressed males, which sport the bright blue plumage with orange breasts and throats, are worthy of anyone’s gaze, but the females aren’t too shabbily dressed either. Lighter, dustier blues and oranges definitely identify her as a bluebird all the way.
The cavity nesting behavior of the eastern bluebird has made this bird vulnerable to habitat degradation and, subsequently, nest-site competition, especially from non-native species of birds like European starlings. But thankfully the birds readily accept artificial human-made structures, and hence the reason bluebirds have rebounded in some parts of its range.
Building bluebird houses—or any birdhouse for that matter—is a worthwhile hobby for young and old people alike. Abundant and simple designs can be viewed and printed from the Internet or selected from umpteen books on the subject, including Minnesota DNR non-game biologist Carrol Henderson’s ever-popular book, “Woodworking for Wildlife.”
And you know it’s not too late to put out new nest boxes, even if a few bluebirds have already trickled into the countryside. Male birds are generally the first to arrive on the breeding grounds (though not always) and the females will soon follow. Male bluebirds will seek prospective territories or return to the same fields they occupied the year before.
I recall one spring day several years ago near my Becida area home not far from Itasca State Park, when I observed what I believed was the simultaneous arrival of a courting pair of bluebirds on their breeding and nesting territory. It was late March when I happened to see the male alight on top of a nest-box while singing and performing “wing-waving” behaviors. The female joined him by fluttering near the entrance hole of the house.
She momentarily suspended herself in front of the opening until she grasped the face of the box with her feet, propped herself upright with her tail for support, and poked her head inside the house for a look-see. As quickly as she performed the inspection, she flew off across the field to another birdhouse (with her suitor seemingly leading the way) where the pair completed the same ritual again. I imagine the house-hunting couple carried out dozens of cavity visits, probably touring both artificial and natural cavities, until she decided upon a favorite nest-site.
After courtship, during which the males often bring food to the female, the pair begins nest-building chores. Both birds assist each other in material collection, but it’s usually the female that constructs the actual nest-bowl. Fine grasses and stems are normal nest material, but so are white pine needles if readily available. Feathers are rarely used, if at all.
Following a weeklong nest construction project, the female lays four to five blue eggs—sometimes white. She alone incubates the eggs (about two weeks) until the eggs hatch. But because the nestlings are born without feathers, the female continues to brood, keeping the youngsters warm and safe, while the male brings much needed food for mother and babies. Soon afterward, when nestlings are a little larger and are graced with a few feathers, mama joins papa for a relentless two to three-week feeding routine.
In all, from incubation to fledging, a month’s time, maybe a little longer, has been consumed. And chances are good that after Mr. and Mrs. Bluebird have ensured that their babies can fend for themselves, will do it all over again and raise another clutch. Often is the case that the first family joins in the rearing of the second clutch. It’s a family affair.
Indeed, it is time to clean your bluebird houses if you haven’t already done so; or make new houses and repair old houses; or put out small bowls of mealworms if you have bluebirds in your backyard . . . all of which are fun activities to be sure; and a most gratifying way of guaranteeing yourself and your blue, blue, bluebirds a spring and summertime’s worth of happiness . . . as we get out and enjoy the great outdoors.
BLANE KLEMEK is a Minnesota DNR wildlife manager. He can be reached at firstname.lastname@example.org