Ruby-crowned Kinglet (Corthylio calendula), a Special Concern species in Wisconsin, is a small bird with a dull olive-green body marked by black-and-white wing bars. Males have a bright red crown that is usually hidden, except when excited. The species is a frequent migrant to Wisconsin and an uncommon summer resident in the north. During the nesting season, the Ruby-crowned Kinglet is found in a variety of forested habitats in the far northern region of the state, most often coniferous wetlands of spruce-fir or tamarack, and less frequently in pine forests at the edge of bogs, and mixed upland, boreal forests of conifers and hardwoods. During the breeding season, the species constructs its nests high in the trees (typically spruce), up to 100 feet high, near the trunk or suspended from small branches. Nests are constructed using an assortment of materials including mosses, grasses, feathers, and spiderwebs. 5-12 eggs are laid and incubated for 12-14 days. The recommended avoidance period is May 20 - August 1.
