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For the last few months a Bewick’s wren has been hanging out in my yard. We hear it much more often than we see it. Its song is one of those I can never seem to associate with the singer (not that my ear for birdsong is all that great; every spring I have to re-learn robin versus grosbeak versus tanager all over again). David Sibley transcribes it as “t-t zree drr-dree tututututututu,” which is supposed to represent a mix of trills and buzzes with a descending pitch. Peterson says it sounds like a song sparrow’s, but thinner. It doesn’t help that the song varies from region to region, and between individuals. Mostly I just wait for the wren—a small brown bird with grayish underparts and a white eyestripe—to show itself. 

Since it is singing, I’m assuming my bird is a male with a territory. And I can’t rule out the presence of a female (Bewick’s wrens, unlike some of their relatives, are monogamous). So nest construction may be getting under way any day now. But unless I catch a wren in the act of transporting material, I’d have no idea where to look for the nest. These birds are very creative in their choice of sites.  

Typical of their family, Bewick’s wrens are cavity-nesters. The main exceptions are the marsh wren, which attaches its globular nest to cattail or tule stems, and the cactus wren, whose nest is sheltered within the branches of a cholla, the spinier the better. W. L. Dawson, author of the classic Birds of California (1923), described the range of documented Bewick’s wren locations: “A cranny of suitable size is the sine qua non, and this may be in a rock-pile, in a canyon wall, in an old woodpecker hole…, under a root, behind a sprung bark-scale, in an old shoe or tin can, or the pocket of a disused coat.” Later observers have added junked cars, cow skulls, and discarded cardboard cartons to the list. One pair nested inside the walls of a trailer; it’s unclear if the trailer was in use at the time. 

Other wren species have similar propensities. One summer in the Sierra, I found a house wren nest in an old boot that had been nailed to a ponderosa pine the previous winter as a snow-level marker. A pair of Marin County house wrens once chose to build in the end of the exhaust pipe of a steam engine, fortunately while it was idle.  

Bewick’s wrens are pretty orthodox in their choice of nest materials. The range is wide—sticks, twigs, straw, feathers, bark, moss, dead leaves, spiderwebs—but the content is mostly natural. That’s not true of some of their relatives, though. Lots of birds will incorporate man-made objects in their nests when available; I’ve seen a Bullock’s oriole nest woven mostly from shreds of blue plastic tarp. But wrens seem to carry this tendency to extremes. Their nests have a great deal in common with the work of obsessive folk artists like Simon Rodia and Grandma Prisbey. 

There seems to have been a tradition among American ornithologists in the last century of deconstructing wrens’ nests and cataloging their contents; I wonder if anyone still has the time and patience for that sort of thing. Arthur Cleveland Bent recorded several such analyses in his Life Histories of North American Birds. One male house wren, for instance, incorporated a hatpin, 67 hairpins, five safety pins, 22 nails, part of a mouse trap, a buckle, six collar stays (this was in 1916), and bits of chicken wire into his nest. Said Bent, “The female refused to accept the nest and departed; I don’t blame her.” 

Rock wrens on the Farallon Islands—the only songbirds that nest out there—have used fragments of discarded batteries, fish hooks, and tacks, along with shards of abalone and mussel shell and the bones of seabirds, fish, and rabbits. (Yes, there were rabbits on the Farallons back in the collar-stay era.) 

But these avian masters of bricolage were outdone by a pair of canyon wrens in Fresno County, who build their nest almost entirely from pilfered office supplies. Employees at a Southern California Edison office had wondered where their paper clips, thumbtacks, and the like were going. The mystery was solved when the wrens’ vacated nest was dissected. It contained over 600 paper clips, 528 pins, 28 rubber bands, 19 thumbtacks, the lid from a glue container, 11 pen points, 87 matches, four toothpicks, and an airmail label. If Post-its had existed in 1931, I have no doubt that the birds would have used them as well. 

I wouldn’t expect anything like this from my Bewick’s wren. But he and his presumptive mate are welcome to the lint from the dryer, if they want it. And I’m tempted to leave a bowl of staples, brads, and paper clips on the back porch in case either of them has a taste for metal. Meanwhile, the prospect of a wren’s nest being just about anywhere—in a broken flowerpot? under the wheelbarrow? in that half-empty bag of redwood bark?—serves as a good excuse for not cleaning up the back of the yard just yet.