I felt lucky to see this little Carolina wren in my office at work this winter. There is a small indoor arena in the building and it’s not uncommon for birds to find their way in there. While unheated, it’s far warmer than the outside temperatures. This is a good spot for a wren or a wren couple this year because we’ve had a very cold winter. The Carolina wren is found along much of the east coast north to Massachusetts and west to states from Texas to southern Michigan but populations are usually drastically reduced after a severe winter.
Thryothorus ludovicianus, the Carolina wren, is the second largest wren in the United States after the cactus wren. It prefers a sheltered habitat with hiding places but this can be in a wide range of places including woodlands, swamps, farms, and residential areas.
The males and females are similar in appearance, the male being slightly heavier and having a slightly longer beak, wings and tail. The back is rusty brown in color and the belly a lighter brown. The tail has dark bands or stripes and the wings have dark and white bands. There is a prominent white stripe through the eye, a characteristic that distinguishes this wren from others. Legs are pinkish. The beak is long and slightly curved and the tail is relatively long. Adults are about 5.5” long and weigh up to 0.75 oz. Young birds are similar to the adults but their colors are lighter. The male is the only one to produce a song but the Carolina wren is known for being one of the loudest songbirds and they sing at any time or place. One report says a captive sang 3000 times in a single day! Listen to the wonderful song here on YouTube.
The average lifespan of the Carolina wren is about six years. They are monogamous so mated pairs stay together until one dies or disappears. Males and females share in the building of the nest, using natural materials like twigs, weeds, pine needles or bits of bark and other found materials such as string or feathers. Nests are built in a diversity of sheltered areas from branch crotches or holes in trees or stumps to mailboxes, windowsills, or discarded containers. The breeding season is from March to October and there can be multiple broods per season, usually two in the northern parts of the range. Nests are usually not reused.
Once the nest is completed, which takes about a week, the female lays 3-7 eggs, usually 4. The eggs are laid one per day, most often in the morning. They are incubated for about two weeks by the female and typically hatch within an hour of each other. During incubation, the male brings food for the female. Once the babies have hatched, both parents feed them for a couple of weeks, then they are coaxed from the nest when the food deliveries are reduced by the adults. While in the nest, young birds are fed caterpillars and other insects. Adults continue to feed on insects and spiders, and even an occasional small salamander or frog. They also feed on berries.
Young wrens will be ready to mate the year following their birth. Males have a ‘showy’ courtship routine that includes hopping in a circle around the prospective female with puffed feathers and a fanned tail. They may even offer her a morsel of food.
Predators of the Carolina wren include hawks, bluejays, raccoons, mink, fox and even squirrels and chipmunks.
If you have a small brown bird nesting somewhere on or near your home or property, it could be Carolina wrens. Look for the white band through the eye and the rather long, slightly curved beak, and listen for the cheerful song of the male.