OUT Column May 13, 2009
Birdhouse boom in Unaweep Divide makes it a migration destination again
A bluebird told me it’s spring.
Relax, there’s no occultism or New Age mentality here, simply the wondrous sight of countless pairs of bluebirds cavorting around the many nesting boxes along Colorado Highway 141 across Unaweep Divide.
Seeing the lapis-bright Mountain bluebirds and the gray-brown females flit around the rectangular nest boxes reminds us that a decade ago, you might have wondered if a bluebird was left in the area.
These are cavity-nesting birds, and as dead trees riddled with woodpecker holes were cut down and wooden fence posts disappeared in favor of the cheaper steel posts, nesting spots attractive to bluebirds disappeared, too.
Which means the birds would arrive on their spring migrations, look around at the dismal housing prospects and keep going.
“I remember driving along Colorado 141 about a decade ago and thinking, “Gee, I don’t see as many bluebirds as I used to,” recalled Bob Wilson of Grand Junction. “I later found out that I was seeing them during the migration, when they are plentiful, but they weren’t staying around to nest.”
Wilson’s nickname and e-mail address are Bluebird Bob, if you want a hint as to where this story is leading.
Wilson decided to tackle the lack of bluebird housing and started building and installing nesting boxes along 141 and elsewhere.
“When I started putting them up I found there were only two bluebird nests on that stretch of 141,” he said. “One was in the gooseneck of a horse trailer and the other was a nesting box put up by a landowner as part of a high school project.”
Initially Wilson used cedar planks, but he later developed a box plan using the discarded ends of plastic fences, which he gets free from a local fence company.
“Now, all I make now are the plastic ones because they have so many advantages, the first of which they don’t cost anything,” Wilson said. “And they last a long time. Some of them have been there for 10 years.”
His venture was an immediate success.
“I was amazed,” he remembers. “That first year I put up about 60 boxes and I think I had nests in 45 of them.”
He estimated he’s put together at least 200 bluebird boxes, which are fastened to fence posts, gates and poles from Gateway to Grand Mesa, Hotchkiss and Paonia.
“I share the design with anyone who wants it,” Wilson said, “Right now, I’m working on some for a landowner on Pinyon Mesa who wants to put up 25 nesting boxes.”
Wilson’s work is tied in with Cornell University’s Laboratory of Ornithology, which runs the citizen science program NestWatch. This volunteer program monitors several bird species each year, tracking distribution, population trends and nesting success.
According to the NestWatch Web site, there now are 42,000 nests nationwide being monitored in the program.
No one knows if the Unaweep Divide birds return to the same box each year. Wilson said a friend in Montana has done some limited banding studies, which indicate some birds return each year.
“A bluebird’s life span is only about 2.5 seasons,” Wilson said. “But we probably raise 200 bluebirds out along Unaweep Divide each year.”
That’s good news for the ranchers, since a bluebird family of two adults and two chicks will eat an estimated 6,000 grasshoppers in the four weeks or so from hatching to fledging when the young leave the nest.
And since most bluebirds raise two broods each summer, that’s a lot of natural insecticide.
“Oh, golf courses love bluebirds,” Wilson said with a laugh.
Most of the bluebirds seen last weekend along 141 were Mountain bluebirds although a couple of Western bluebirds (rusty sides and back) were noted.
“A few years ago there was a backyard near Tiara Rado (golf course) where all three species (Mountain, Western and Eastern) would nest but I haven’t heard of it recently,” said John Toolen, an ecologist leading Saturday’s field trip across Unaweep Divide to the Dolores River and John Brown Canyon. “I think it was the only place in the U.S.
where all three species would nest.”
The trip was part of the Grand Valley Audubon Society’s annual Spring Bird Count, a one-day count pinpointing migratory neotropical songbirds as they pass through western Colorado.
Our group of four tallied 59 species of birds, a bit down from last year’s numbers.
Missing were some of the commonly seen birds such as warbling vireos, spotted towhees and Sandhill cranes.
But there were plenty of bluebirds.
“Yep, there’s a lot of them out there now,” said Wilson with a soft chuckle. “It’s very satisfying to have contributed to something like that.”