Fact Sheet to Accompany Cavity Nester Matching Game
Descriptions of nests made by birds that use nestboxes
Eastern Bluebird: Neat, cup shaped, woven nest of 100% fine grass or pine needles. Occasionally bits of fur or some feathers. Fairly deep nest cup. Eggs are powder blue, sometimes white.
House Sparrow: Jumble of odds and ends, including coarse grass (with seed heads), cloth, feathers, twigs and sometimes litter. Tall nest with tunnel like entrance. Eggs are cream, white, gray or greenish, with irregular brown speckles. NOTE: House Sparrows are non-native invasive pests, and are not protected by law. They will attack and kill adult bluebirds (sometimes trapping them in the nestbox), and destroy eggs and young. House Sparrow nests, eggs, young, and adults may be legally removed or destroyed under U.S. Federal Law. It is better to have no box at all than to allow House Sparrows to reproduce in one.
Tree Swallow: Nest of grass lined with feathers. Flatter cup than bluebirds. Eggs are pure white.
Black-capped Chickadee: Downy nest of moss , fur, and soft plant fibers. Female may cover eggs with moss when leaving the box. White/cream eggs with brown speckles.
Tufted Titmouse: Downy nest of moss, fur, and soft plant fibers. May have earwigs living under it. Eggs are white with rose/mauve speckles.
House Wren: Messy nest of twigs, occasionally lined with fine fibers or feathers, usually filling box. Males may build eggless "dummy nests" in nearby boxes to reduce competition. Tiny glossy white eggs, sometimes tinted with pink/buff, with many pinkish brown/reddish brown/brown specks that sometimes form a ring on the larger end of the egg.
Brown Headed or White Breasted Nuthatches, and Ash Throated and Great Crested Flycatchers, Bewick's Wrens, Carolina Wrens, may also use Eastern Bluebird nestboxes. Flying squirrels may also use boxes. Woodpeckers (e.g., Downy woodpeckers) may enlarge the entrance hole and roost in bluebird nestboxes. Gray or red squirrels or starlings may occupy boxes with holes larger than 1.5 inches.
NOTE: It is illegal to disturb a nest with eggs of any bird except House Sparrows, starlings and pigeons, which are not protected. Empty House Wren nests can be removed.