By Clay Christensen
I was walking in the neighborhood a few years ago and passed my neighbor Paul’s house. He was in the yard and came over to ask me a question about bird identification. He said he had seen this little brown bird, creeping up a tree trunk. What did I think it was?
“That’s called a brown creeper,” I said. He seemed incredulous, like I had made up the name on the spot.
We have several species of birds that creep up and down our trees in the winter, including four or five woodpecker species. The brown creeper is usually around all summer as well, but they’re easier to see in the winter.
It’s a small bird, just more than 5 inches long, with a streaky brown head, back and tail. The bill is thin and curves downward, just right for probing under tree bark. The white dots on the wings add to its camouflage.
The brown creeper is the only member of the creeper family in North America. In Minnesota, it breeds in May through July, from the Canadian border down to central and southeastern Minnesota.
It looks rather pudgy as it clutches the tree trunk. It’s secretive, although it doesn’t seem bothered much by a person approaching it.
The brown creeper usually forages up a tree trunk (never down), in a series of hops, often circling the tree as it ascends. It has sharp tips on the ends of its stiff tail feathers that help prop it against the trunk.
It favors trees with larger trunks whose deeply furrowed bark has more hiding places for the creeper to probe and pry, looking for insect eggs, larvae, spiders or hibernating insects.
When the creeper has gone as high as it wants on one tree, it flies to the base of another tree and begins its upward climb again. They’re easiest to spot as they fly to a new tree. There’s a buffy band on both the upper and underside of the wings that make it a beauty in flight.
I love the quote by Dr. W.M. Tyler, who wrote about the bird in A.C. Bent’s Life Histories of North American Nuthatches, Wrens, Thrashers and their Allies: “The brown creeper, as he hitches along the bole of a tree, looks like a fragment of detached bark that is defying the law of gravitation by moving upward over the trunk, and as he flies off to another tree he resembles a little dry leaf blown about by the wind.”
The brown creeper’s call is usually two high-pitched, sibilant tsee notes. It’s actually a hearing test for me. At my age, whenever I can hear the brown creeper call, I figure I have at least a smidgen of high-frequency hearing left. It also has a beautiful song, starting with those two high-pitched notes and descending in a warble that rises at the end, usually sung by the male on its breeding grounds. You can hear a recording of the song at http://tinyurl.com/b-creeper.
The brown creeper often gathers with black-capped chickadees, golden-crowned kinglets, dark-eyed juncos and downy woodpeckers in mixed flocks early in the winter.
Brown creepers use empty woodpecker holes as an overnight roost in the winter, sometimes communally. An observant birder once found three of them using a woodpecker hole. They were tucked headfirst into the hole, just at eye level, their camouflaged bodies making them hardly noticeable to passersby.
In the spring to early summer, the brown creepers begin to build a unique nest under a flap of loose bark, the pair working together. The male helps gather material that the female uses to attach a hammock-like sling to the underside of the bark, and then she builds a nest cup in the hammock. The entrance to the nest is usually at the bottom, the exit often at the top.
When the nest is ready, the female lays an egg each morning until she has a clutch of five or six. The eggs are white, about 5/8 inch long, with pink or reddish-brown spots at the large end.
The female incubates the eggs for the next 15 days. The male brings her food while she sits on the nest. All the eggs hatch at the same time.
Both adults are cautious when approaching the nest, making several preliminary stops to divert the attention of any predator that might be watching. They spend an average of less than three seconds in the nest while feeding.
The nestlings fledge in about 17 days, and another generation of little brown creepers begins to delight us by imitating a piece of detached bark moving up a tree trunk.
Clay Christensen watches and writes about birds from his home in Lauderdale.
Breeding Bird Atlas topic of next Audubon talk
Bonnie Sample, coordinator for the Minnesota Breeding Bird Atlas, will talk about the atlas on Thursday, March 14, at 7 p.m. at Fairview Community Center, 1910 W. County Road B, Roseville. The free St. Paul Audubon Society program will look at Minnesota’s first Breeding Bird Atlas, a five-year, citizen-science project that will document Minnesota’s breeding species and their breeding distribution. It is likely that members of the St. Paul Audubon Society have contributed to it.
Participants will learn why the atlases are important, how they work and the progress made to date in Minnesota. Sample will also tell a few interesting stories and finish the talk with a look into the future.
To learn more about this topic, visit www.mnbba.org.
The event is open to the public. A social time with refreshments begins at 6:45 p.m. For more information, call Linda Goodspeed at 651-647-1452.