Nest characteristics are helpful in identifying species that have taken up residence in your nesting structure. More information on nest ID can be found at, part of The Cornell Lab of Ornithology.


Huge balls of grasses, weeds, or trash, with the opening on the side of the nest. Some include feathers, hair, or string. Nests are noticeably messy. Eggs are white to greenish white with a slight gloss and are dotted with grays and browns. 3–7 eggs, commonly 5.


English House Sparrow nest. Photo by stevesunusual licensed under CC BY-NC-ND 2.0.


Characterized by loosely arranged fine grasses and weed stalks. The hollow in the middle for eggs is typically about 3 inches in diameter. Eggs are pale blue to bluish white, with an occasional white egg. 3–6 eggs, commonly 4–5.

Left: Nest with newly hatched Eastern Bluebird chicks. Right: Bluebird nest with white eggs.


Nest is an accumulation of dry grass, hollowed in the center or in the corner, lined with feathers that are often placed so the tips curl over the eggs. Eggs are pure white and smooth with no gloss. 4–6 eggs.

Tree Swallow Nest. Photo by Terrie Schweitzer/Flickr.


Bulky mass of leaves, twigs, mosses, rootlets, and weed stalks. Generally domed at the top with a side entrance, lined with feathers, leaves, moss, and hair. Smooth eggs with little or no gloss are white to pale pink typically marked with brown spots, concentrated at one end. 4–8 eggs, commonly 5–6.

Carolina Wren nest


The bottom of nest is lined with bark strips, deciduous leaves, moss, and grass. Nest is “cupped” and lined with hair, fur, or bits of string or cloth. Eggs are creamy white evenly speckled, with small spots often concentrated at the larger end. 4–8 eggs, commonly 5–6.

Tufted Titmouse nest