Creeper chase
Do you have any fairly common species that are just so difficult to locate? Reports from all over indicate that people are seeing this species routinely, but you just can’t seem to find it? For me, that bird, my nemesis species, is the brown creeper.
Creepers are not a difficult species. You can find them right in the city, in areas of mature trees of various kinds. They are not as obvious as the chickadees and nuthatches they often hang out with in the winter, but they are there a whole lot more often than I see them, that’s for sure.
Several years ago I was doing a Big Year, trying to see as many species in Kootenai County as I could. Lots of people saw brown creepers in January. Just about everyone had seen one by summer. I saw only a single creeper that whole year, and that was not until September.
It has always seemed curious to me that I should have such difficulty finding this little bird. True, it is cryptic – colored the same as the cracked and weathered bark it creeps on. In fact, one field guide describes the brown creeper as a “piece of bark come to life.” That is an apt description. But I don’t require bright coloration to find birds. I find plain, nondescript birds all the time.
In the dead of winter, when hardly a bird is to be found, I can always find an example of the smallest of the wrens, a winter wren, tucked into the base of a thicket somewhere. Winter wrens are both plain and tiny. With this little species, one usually doesn’t see the bird at all at first. You hear its faint tick-tick call, then you locate and see it. In the silence of a deep winter’s day, winter wrens actually become pretty easy, as long as you are listening carefully.
The day after Christmas I was walking alone through Coeur d’Alene City Park, listening intently for the sound of pygmy and red-breasted nuthatches to indicate the presence of a mixed winter flock foraging in the area. Usually you can detect the nuthatch calls long before the cheerful, playful calls of the chickadees that are generally traveling with them.
Much of the park was too noisy with the voices of people – what they were doing out on such a cold and damp day, I do not know – and starlings. But in one particularly dark and quiet section of the park, there was the high but faint tsee-tsee call of a golden-crowned kinglet. The kinglet call is quite distinctive in the crisp winter air, and it’s a good thing, too, because seldom, it seems, do you actually get to see one. Kinglets are so small and secretive and usually so far up in the densest part of the overstory as the flock moves by, that hearing them is often the best that you can do.
On my third pass through this area, not even looking for the invisible kinglet, a brown creeper suddenly alighted at the base of a huge maple just a few feet away from me. Then it started its characteristic climb, making a spiral up the trunk of the tree. Once it was two-thirds of the way up, it flew to the base of an even larger old spruce and repeated its woodpeckerlike trek up the tree.
Naturally, I was thrilled at this unexpected and, for me at least, rare treat. Then I realized that a kinglet, as tiny as kinglets are – only about 4 inches long compared to the 51/4 inches of a creeper – must be hiding behind the creeper on the tree trunk. Why was that? Because the kinglet call kept coming from wherever the creeper was. But when the brown creeper flew to the next tree, I had to admit that the only sound around was coming from the creeper.
Brown creepers are not particularly shy, so there was a long opportunity to watch and listen to this particular bird. And then it struck me – for all my many years of chasing birds, I could not recall ever hearing, or at least paying attention to, the call of a brown creeper. Most creepers have been in the company of the much louder chickadees and nuthatches that make up the roving winter flocks I so love to hear on bleak winter days.
Of course there were always the invisible kinglets in those flocks that I would only hear. Well, obviously, my ability to identify birds by sound has been a weak point in my birding career. And it turns out, that is exactly why I have missed so many brown creepers over the years. Instead of looking for the mystery bird after first hearing it, as is the case with winter wrens, I have simply assumed the presence of an invisible kinglet and left it at that.
You see, brown creepers are not easy to spot if not expected, just as with the winter wrens. They hug tightly to tree bark as they spiral their way up, and they generally work alone, even when associated with the typical roving winter flocks containing the two nuthatches, up to three species of chickadees, kinglets – actual, the-real-thing, kinglets – juncos, and often a downy woodpecker.
And as I mentioned before, brown creepers do not stand out in a crowd or when alone. In fact, when alarmed, they flatten themselves against the tree trunk and spread their wings and tail, becoming more invisible than any kinglet ever hoped to be. When they do fly, it’s usually not far, and it’s in the same undulating, woodpeckerlike pattern of the nuthatches.
So, for me at least, they are easily missed – were easily missed. From now on, I will apply my winter wren strategy and will be clued in to a creeper’s presence by first hearing its call. The problem still remains, however, that my creeper from the other day sounded to me as if it was a kinglet. It gave a definite-but-faint tsee-tsee call. So when I got home I pulled out several (actually, five) field guides and a few (actually, six) reference books to sort this thing out.
What did I find? Confusion. My birding bible, “The Sibley Guide to Birds,” describes the golden-crowned kinglet call as “a very high, thin, slightly buzzing zree or zee-zee-zee.” The brown creeper call, on the other hand, is “a very high, thin, quavering seee or sreee similar to golden-crowned kinglet … often buzzier, often double teeesee.”
Now, can you “sreee” the difference? Me either. I don’t have an ear for the subtleties of music, and I certainly don’t have an ear for the subtleties of bird calls. Don’t even get me started on warbler songs, those patterns that I have to – that I attempt to – relearn each season.
And the other guides were no better. For kinglet verses creeper: see-see vs. tseeeee – yes, five e’s (Kaufman), “3-5 very high creeperlike notes” versus “a single very high note” (Golden), “see-see-see” versus “a single seee, similar to … kinglet” - 2 e’s versus 3 (Peterson), and, my favorite, “a series of high, thin tsee notes” versus “a soft, sibilant see” (National Geographic).
Sibilant? I had to look it up. My computer’s thesaurus had no idea. Encarta online finally recognized it as “a hissing sound … air escaping from a tire.” So, what is it, SEE or TSEE or ZEE, and exactly how many E’s? I felt vindicated, however, when that last guide concluded the creeper description with “fairly common but hard to spot.”
By the way, the call of the winter wren is a chat-chat, a kimp-kimp, a tick-tick, a kip-kip, or a timp-timp, sounding like either a song sparrow or a Wilson’s warbler, depending whom you want to believe. To me, they sound like a winter wren, and I’ll leave it at that.
Despite my frustrations over not seeing brown creepers, I have always found them to be a fascinating species. Our brown creeper is the only North American member of the family of birds referred to as “tree-creepers” in the rest of the world. I like that name. Someone has actually proposed changing the name of the brown creeper – such a colorless name – to “American tree-creeper.” By the way, all the creeper species of the world are brown.
Our tree-creeper’s closest relative, listed as being in the same species until 1982, is the Eurasian tree-creeper. Guess where it’s found? Our creeper lives, generally year round, from Alaska to Nicaragua. In North Idaho we can expect to find creepers wherever mature, rough-barked trees are found. They are probably in higher numbers at lower elevations this time of year, especially when the winter is severe.
In North America, the brown creeper’s closest relatives are the wrens, although most field guides place them with the nuthatches. If you had to pick a group to place them with based on appearance and behavior, however, you’d want to call them miniature woodpeckers.
Creepers have strong feet with large, sharp claws for grasping bark. They have an extremely stiff tail that they use to prop themselves against the bark. They even molt their tail feathers in the same, unique way as woodpeckers, allowing them to use the prop no matter what their feather condition. And they climb trees in the same jerky, always upward motion as do the woodpeckers.
But woodpeckers and creepers are not anywhere near close to each other on the bird family tree, so to speak. So, why are they so similar in how they look and forage? Through the mechanism of convergent evolution. In this process, different types of organisms develop similar adaptations to take advantage of similar ecological conditions.
Creeper beaks have not, however, converged with woodpecker beaks. Creepers do not pound the bark looking for their diet of insects, spiders and their eggs as both woodpeckers and nuthatches do. Instead, they use their thin, downward curved bill to probe the crevices and cracks of the rough bark they seek out to climb on.
They are, in fact, so bark-dependent that they roost at night hanging onto the side of a tree. They even build their nest, a hammock-shaped structure, suspended behind a slab of sloughing bark on a snag. Creepers may also form small communal roosts behind similar sheets of loose bark in the winter.
Speaking of nests reminds me of something else that I learned in my study of creeper linguistics. I just can’t leave this call thing alone. In the spring and summer, male brown creepers have a beautiful song that they use to defend their territory. Apparently it is not like that of any other bird. In fact, it is described as sounding like “trees, trees, beautiful trees.” Really. I read it in two different places.
The big take-home lesson from all of this? After 37 years of birding, I can still discover new things about the common birds around me, and I can still have one of those “ah-ha” moments in the field without having to trek off to exotic destinations. The adventure, and the learning, never has to cease.