This photo was taken by Dallas County Master Gardener Mark Jones while volunteering at the Salvation Army Gardens.  The mother bird was not in sight.

Identifying eggs from photos can be tricky, especially as there are several birds breeding in North Texas that lay bluish, speckled eggs, and colors in photos can sometimes be distorted. The task is made harder because egg size can be key to identification, and photos may not accurately depict the egg’s true size.  In the absence of a parent bird, the location and composition of a nest can often give important clues to the identity of the builders.  In this case, the nest is located about four feet off the ground in a Vitex tree located in a suburban-like setting.

Of the birds that lay blue-speckled eggs in Texas, the Blue Jay, Northern Cardinal, and Northern Mockingbird are the ones you are most likely to encounter in a suburban setting. At first glance, these eggs seem to fit the description of Blue Jay eggs, but Blue Jays build their nests in the crotch or thick outer branch of a deciduous or coniferous tree, usually 10 to 20 feet off the ground.  If we rule out Blue Jay, that leaves Northern Mockingbird and Northern Cardinal.  Consulting Cornell Lab of Ornithology’s website, All About Birds  https://www.allaboutbirds.org/guide/ , we find this information:

Description of Northern Cardinal nest: “nests tend to be wedged into a fork of small branches in a sapling, shrub or vine tangle, 1 to 15 feet high and hidden in dense foliage. They use many kinds of trees and shrubs, including dogwood, honeysuckle, hawthorn, grape, redcedar, spruce, pines, hemlock, rose bushes, blackberry brambles, elms, sugar maples, and box elders. The nest cup has 4 layers: coarse twigs (and sometimes bits of trash) covered in a leafy mat, then lined with grapevine bark and finally grasses, stems, rootlets, and pine needles…the finished product is 2 to 3 inches tall, 4 inches across, with an inner diameter of about 3 inches. Egg description: Grayish white, buffy white, or greenish white speckled with pale gray to brown.”

Description of Northern Mockingbird nest:” Northern Mockingbirds nest in shrubs and trees, typically 3 to 10 feet off the ground but sometimes as high as 60 feet…Mockingbird nests consist of dead twigs shaped into an open cup, lined with grasses rootlets, leaves and trash, sometimes including bits of plastic, aluminum foil, and shredded cigarette filters. Egg description: pale blue or greenish white splotched with red or brown”

Since we don’t have access to the nest to measure its size or analyze the materials it is made from, we must rely primarily on the egg coloration as our key identifying clue. Based on the nest’s location and the color of the eggs, the most likely species to have built the nest is the Northern Mockingbird.