The Carolina Wren Nesting Preferences
Carolina wrens prefer natural nesting sites located in woodlands, thickets, brushy hollows, and swamps and along the banks of streams where there is plentiful cover. They usually make use of woodpecker holes, the open crotch of a tree, the upturned roots of a fallen tree, on the ground under dense undergrowth or again near tree roots, in holes on stone walls and even in grain sheaves in open fields. In short, they prefer to build nests in low elevations.
Due to the growing density of human population Carolina wrens do not always have the option to build nests in wild spots like that. However, Carolina wrens do not have a really difficult time adapting to their environment and are fairly tolerant of human activities. In fact they often use man-made objects such as glove compartment of abandoned cars, garages, old shoes, bird houses, shelves, mailboxes, pockets of old coats, covers of propane tanks, pails, pitchers, tin cans and pretty much any kind of snug nook and cranny available as their nesting holes. Carolina wrens have also been reported nesting in old hornets nests and ivy vines that grow in porches.
Like the House wren, male Carolina wrens are the one that start building the nests. The male Carolina Wrens fills many holes and whatever places around its chosen territory with sticks to build the very base of the nest. Aside from sticks the male birds are partial to using soft and pliable materials like grasses, weed stalks, strips of inner bark, leaves, mosses, rootlets, and feathers. They are also known to frequently make use of snakeskin. Snakeskin is more often used for lining the nest though instead of serving as the base of the nest. When the female arrives it then chooses among the nests prepared by the male Carolina wren. Again like its cousin, the House Wren, the female Carolina wren may disagree with the choices the male wren made. Upon choosing a specific nest the female takes over the nest building and lines it with even softer materials. The nests lining is usually composed of fine grass, fine rootlets, hair, feathers, snakeskin and sometimes Spanish moss. Carolina wrens that range in Texas are known for using stranger nesting materials though like small twigs, corn husks, pieces of paper, string, thread, wool, rags, and leaf skeletons.