Bluebirds Thrive with Help from their Friends
Americans have done great work resurrecting species like elk, wolves, grizzlies, whitetails, pronghorns, wild turkeys, sandhill cranes and Canada geese the past century.
And lord knows some advocacy groups would go bankrupt without their favorite charismatic poster-critter inspiring and reminding us of their noble work.
Meanwhile, other groups have helped equally needy species with far less fanfare, fundraisers and junk mail, and achieved equally impressive results. For example, you won’t find a more humble but productive conservation group than the Bluebird Restoration Association of Wisconsin.
Consider: The North American Breeding Bird Survey recorded a mere 22 eastern bluebirds in Wisconsin in 1979. Insecticides and pesticides like DDT helped ruin them, accumulating in the bluebirds’ bodies through bugs and other prey they ate, and coating their eggs inside the nesting hollows of aging apple trees.
Meanwhile, natural nesting cavities also faded. Apple growers switched to shorter-lived and less substantial trees, and farmers replaced rot-hollowed wooden fenceposts with metal stakes. In addition, invading hordes of European starlings and English house sparrows claimed the remaining nesting hollows for their own broods, evicting the bluebirds.
Wisconsin’s birding community recognized the bluebird’s plight, spread the word, and rushed to their garages and basement workshops to build bluebird boxes and install them along pastures, park trails and rural roads. By 1986, with 600 nesting pairs verified, the Wisconsin Department of Natural Resources’ endangered species bureau gave order to the effort, which soon spawned BRAW (braw.org).
Patrick Ready, 65, of Madison, is president of BRAW, which has 600 members. Ready recalls when bluebirds were rare, and didn’t see his first until he was 28 in 1982. He was hiking that April day in the southern unit of the Kettle Moraine State Forest, and heard a pretty, but unfamiliar, song from atop a nearby tree. It was a male bluebird claiming its territory.
Ready can’t pinpoint how many bluebird pairs nest in Wisconsin today, but in 2018 BRAW observers counted 18,695 bluebird fledglings in the 8,000 nest boxes they monitored. That’s a vast expansion from 30-some years ago, but it’s actually a 20 percent decline from BRAW’s count in 2017, which identified 23,266 fledglings.
In fact, the 2018 tally was the third straight annual decline in fledglings, and down 42 percent from a record 32,000 fledged bluebirds in 2012. That record followed eight straight springs of good nesting conditions.
Ready said BRAW’s long-term average for fledglings is 20,000, but sees no reason to panic about the current three-year dip. After all, he can explain it. “The weather in 2018 really hurt bluebird production statewide,” Ready said. “We lost a lot of birds last spring in central and northern Wisconsin after that blizzard hit in mid-April. Snow covered the ground for weeks. And we had a lot of cold rain the previous May, so the birds have had a hard time.”
Ryan Brady, the DNR’s bird-research biologist, said he doesn’t expect the snowstorm that hit Wisconsin last week (April 10-11) will devastate bluebirds, robins and other returning migrants. Brady said April snowstorms aren’t unusual or deadly unless the snow refuses to melt. In that case, the snow separates birds from insects, grubs, worms and leftover berries.
Meanwhile, Ready and other BRAW members have been building and installing their preferred NABS birdhouses, a model designed by the North American Bluebird Society. These houses have 4-by-4-inch and 4-by-5-inch nesting platforms, and a 4- to 5-inch cavity below the box’s entry hole.
Unlike most birdhouses, however, you can’t just install a bluebird box and return to gardening, mowing or fishing till the occupants migrate south at summer’s end. Bluebird boxes require forethought, attention and commitment.
Ready said bluebird observers must choose sites in fairly open habitat, and place their boxes at least 100 yards apart to provide nesting pairs adequate turf. BRAW recommends mounting the boxes atop ¾-inch steel pipe that’s 6 feet, 8 inches long. Nest raiders like cats, snakes and raccoons can’t climb narrow pipe.
In addition, BRAW recommends facing bluebird boxes east to keep prevailing westerly winds from blasting through the entrance hole. Boxes pointed easterly also heat more quickly in the morning, but don’t overheat in the afternoon like boxes facing south.
Once BRAW observers install all their boxes, they must monitor them weekly to ensure sparrows, starlings, blackflies and other pests don’t ruin their effort. If bluebirds don’t take up residence after two Aprils, observers move the box to a better site. And if you can’t keep sparrows away, move the box to sites without sparrows. That usually means far from farm buildings or homes where people feed sparrows.
Ready recommends installing bluebird houses before the birds return in March and April, but don’t panic if you start late. If you finish your work before July Fourth, you still might help a nesting pair. He recalls installing a box in late June one year, and finding a nest with eggs a few days later. Many pairs produce two broods each nesting season, and can even have three broods if they start in early spring and end in late summer.
When Ready considers the bluebird’s future in Wisconsin, his main concern is their dependence on bluebird geeks like himself. “They’ve come to depend on man to build their houses and constantly monitor their nesting situations,” he said. “If we were to quit looking in on them, I think their numbers would plummet again.”
Unfortunately, when Ready looks at his fellow BRAW members, he sees an aging crowd and few younger people. As with hunters and anglers, birdwatchers aren’t backfilling their ranks.
“I’m starting to get near that age-out time,” Ready said. “We need to recruit more young people, but they don’t see the need for building bluebird boxes and monitoring them.”
Bluebird pairs often produce two and occasionally three broods each nesting season. (Patrick Ready photos: 1, 2; Jack Bartholmai photo: 3, far right)