Early in the season, American Robin parents often build their nests low in an evergreen tree. Later in the year when the leaves have returned, robins prefer high spots in deciduous trees. Adaptability is an important skill for bird parents, especially in species that might produce more than one brood per year, such as the American Robin. As the environment changes throughout the spring and summer, ideal nesting sites change. Once a pair has decided on the ideal spot, they use plant matter dipped in mud to build a strong nest in which to raise their young.
A female American Robin reinforces her nest with mud. Females build the nest from the inside out, pressing dead grass and twigs into a cup shape using the wrist of one wing. Other materials include paper, feathers, rootlets, or moss in addition to grass and twigs. Once the cup is formed, she reinforces the nest using soft mud gathered from worm castings to make a heavy, sturdy nest. She then lines the nest with fine dry grass. The finished nest is 6-8 inches across and 3-6 inches high.
This video accompanies Chapter 11, Breeding Biology of Birds, Handbook of Bird Biology, 3rd Edition from the Cornell Lab of Ornithology and Wiley Publishing.
Recorded by Marie P Read, Macaulay Library