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CAROLINA WREN:
SOUTH CAROLINA'S STATE BIRD

After posting last week's photo essay about Carolina Jessamine--South Carolina's state flower--we heard from several other state symbols who insisted we write about them, too. From the farm that adjoins Hilton Pond Center, several cows mooed loudly that we publish an installment about Milk being the official state beverage, and a recently hatched Carolina Mantid prayed that we would give him his due as the state insect (below right). During the week an Eastern Tiger Swallowtail sailed by our window, trailing hindwing banners that appeared to request an article about its prestigious position as the state butterfly. However, the state symbol that really got our attention was a boisterous Carolina Wren that for the past seven days has repeatedly called for us to remind the world that he IS South Carolina's designated bird--and HAS BEEN since 1948. We always thought Carolina Wrens were crooning "kettle-tea, kettle-tea, kettle-tea," but now we realize the actual wording of their song is a highly demanding "picture-me! picture-me! picture-me!" In deference to the wren's request--and as an attempt to quiet his incessant dawn-to-dusk singing--this week we offer photos and information about the Carolina Wren, South Carolina’s Official State Bird.

All text & photos © Hilton Pond Center

Carolina Wrens sing their song beyond South Carolina, of course, from Mexico north to the Mid-Atlantic states and west to eastern Nebraska. Although the species appears to be expanding into New England, Minnesota, and southern Canada, Carolina Wrens are nonmigratory and accustomed to somewhat warmer climes, so many individuals perish during cold weather at the northern edge of their range. Spring through fall they consume many kinds of adult and larval insects; in winter, they often survive by eating berries or suet and picking through chaff under feeders in search of bits of edible sunflower seed. Like most wrens, this species has heavy barring on wings and tail, but the buff-colored breast is unbarred. Other useful field characteristics include a distinctive white eyeline, whitish throat and cheek, and a long decurved bill that the male opens wide when he tilts his head back in song.

Actually, the Carolina Wren that has been singing so loudly this week just outside the old farmhouse at Hilton Pond Center has reason to crow. His mate is sitting on five eggs in a nest that we discovered, quite by accident. In a fit of spring cleaning last week, we moved all our recyclables onto the front porch, where they sat waiting for the recycling center to open the following Monday. We also gathered up a small pile of roadside trash that some thoughtless litterbug had pitched from a passing car. We jammed the litter into a aqua-blue plastic bag from Belk's department store (below left) and placed it on an old "glider" lounge chair on the porch, intending to dispose of the litter bag when we hauled off the recycling.

We should have remembered that, at this time of year, Carolina Wrens are not likely to let any inanimate object go unexamined as a potential nest site. In past breeding seasons, we've found wren nests in the front grill of our 12-passenger van, behind the spare tire on the Center's utility trailer, under the cover of a propane gas tank, and--a little more logically, we think--inside several different nestboxes we erected around the property for Eastern Bluebirds. The nest in the van grill was by far the most unusual, and the most traveled--mostly because the wrens built their nest in the vehicle without our knowledge.

Here's the amazing story: One spring morning, after making the 25-mile round trip from York to Rock Hill and back, we noticed two Carolina Wrens buzzing around the front of the van, which by now was parked in the driveway. While we watched, one of the wrens darted into the grill near the left headlight. When we walked closer to the vehicle, we saw a few blades of grass protruding, and a closer look showed a nest plastered right up against the radiator. Incredibly, the nest still contained an infertile egg and four day-old chicks--the latter of which had survived the morning excursion to Rock Hill despite what must have been rather high engine temperatures and a pretty good rush of wind when the van was moving. We didn't drive the vehicle for the next week and, sure enough, were pleased eventually to see flitting around the yard a family of six wrens--two adults and their four cosmopolitan youngsters. (Which brings us back to the aqua-blue litter bag on the front porch at Hilton Pond.)

On Monday this week we began loading our temporarily stored recyclables for transport to the convenience center. Since we had corrugated board, cans, glass bottles, newspapers, and sundry plastic containers, we probably made a good bit of noise packing up stuff and tossing it into the back of our van. After all the recyclables were stowed, we leaned to pick up the aqua-blue litter bag and were startled as a Carolina Wren exploded from its depths, missing our head by only an inch or two as it followed an escape route past and then under the parked van. We knew immediately not to grab the litter bag, lest we damage a nest we figured must be within. Sure enough, down inside the bag--right on top of the roadside trash we had collected--was a mass of sticks and leaves and grass woven into an cave-like nest that contained five spotted eggs. That'll teach us to leave lying around anything that even remotely resembles a potential Carolina Wren nest site!

Wren nests are fairly distinctive. The family name (Troglodytidae) comes from the Latin word for "cave-dweller," and a cavern is just what the nest looks like. (By the way, the Carolina's Wren's technical name, Thyrothorus ludovicianus, has nothing to do with South Carolina and means "reed-jumper from Louisiana.") The base, sides, and "lid" of a nest--which are all constructed by both sexes in Carolina Wrens--is usually sticks, stiff grasses, and a leaf or two, while the interior may include pine needles and other dried herbaceous matter. The female puts the finishing touches on the structure, usually lining the cavity with soft grasses and sometimes hair and moss. In the case of our front porch litter bag nest, it was only appropriate that the piece de resistance was a piece of cellophane that looked like it came from a throw-away cigarette pack.

The female Carolina Wren had been sitting pretty tight on the nest all week, even though vehicles, the UPS man, family members, and various visitors were in and out of the adjoining carport numerous times. Several folks passed within a yard or so of the nest, and the wren just kept sitting. Since she was so attentive, we decided to set up a tripod and camera nearby so we could try to get a photo of her while incubating. She posed quietly (above), and later--when she left the nest to attend to personal matters--we also got a shot of two of the eggs nestled against the shiny cellophane nest-lining (below).

We noticed this particular female Carolina Wren left the nest about every 90 minutes, probably to stretch her legs, defecate, and maybe gulp down a caterpillar or two before returning to incubation duties. Typically, the much-more-skittish male visited about once an hour to bring a choice morsel of food. On warm afternoons, the female was off the nest for up to ten minutes--certainly not too long a time with ambient temperatures in the upper 80s. At midday on 21 April, however, she was gone for almost a quarter-hour, so we rushed to the backyard of the Hilton Pond farmhouse to find she'd gotten snared in a mist net we had erected to catch hummingbirds. We quickly disentangled her and read the number (1571-50173) that told us we'd just banded her two days previously after catching her in the very same net.

During both captures the Carolina Wren female had a well-developed "brood patch"--an interesting adaptation shown by most songbirds. It seems that, stimulated by hormones in spring, many female passerines begin losing their belly feathers or even plucking them out. This provides a bare expanse of skin that also becomes vascularized (filled with blood vessels) and wrinkled and edematous (from retained fluids). The result is essentially a "hot water bottle" that has no feathers to impede highly efficient transfer of a bird's body heat to her eggs or newly hatched chicks. In some birds--most woodpeckers, for example--males also get brood patches and share incubation duties.

After reading her number and photographing her brood patch, we released the recently netted Carolina Wren and watched as she flew back to the front porch toward the aqua-blue litter bag. Without hesitation, she dived into the nest and immediately snuggled up against the eggs, none the worse for her most recent mist net experience.

Since the incubation period is about 14 days, we expect the Carolina Wren's eggs to hatch sometime around the last weekend in April, after which she and the male will have their bills full finding enough succulent insects to satisfy the cravings of their ever-hungry nestlings. The chicks will fledge two weeks after hatch day, and the male will likely tend to them a while longer while the female cranks out another clutch of eggs. In the meantime, should you happen to visit Hilton Pond Center, do not think we are lazy housekeepers who let the trash pile up on our front porch. We're merely trying to be good landlords for another generation of Carolina Wrens who decided to exercise their prerogative as South Carolina's state bird by building a nest anywhere they darn well pleased!

All text & photos © Hilton Pond Center

NOTE: Be sure to scroll down for an account of all birds banded or recaptured during the week, as well as some other interesting nature notes.

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