Wild Things: American Robin (Turdus migratorius)

This familiar “robin redbreast” is our largest thrush, at 8-11 inches in length. The odd name comes from the family name, Turdidae, and the fact that the species migrates southward in flocks in winter. Robins are widespread, occurring year round throughout the U.S. except the far southern border where they are found only in winter. In fact, Partners in Flight reports that the American Robin is the most abundant bird in North America, with the population numbering nearly 400 million individuals. Robins are present year-round throughout New Mexico. The breeding season distribution extends across most of Canada. Males have a dark gray back and black head with thin white stripes down a black throat. The bright reddish-orange breast is the most distinctive feature. Females are similarly colored, but though with lighter, less striking plumage.

Robins are habitat generalists, occurring in hardwood, coniferous, and mixed forests, farmlands, fields, and suburban lawns, where they hop around on the ground pursuing elusive earthworms and insects. They are particularly adept at seeing, and possibly hearing, an earthworm or grub from distances of 6 feet or more as they stand still and survey a lawn. Then they will run over and grab the insect and pull it from the ground. Hunting on lawns exposes the Robin to any herbicides or pesticides that may have been applied by homeowners and can be a source of mortality in the local population. They will also visit bird feeders. Robins have also been reported to occasionally consume small vertebrates. Robins disappear from suburban neighborhoods in winter but may be seen out in forested settings where they congregate in large flocks and move around in search of foods like berries and other seeds and nutritious plant matter.

Males sing their melodious, flutelike song in short phrases lasting several seconds each to advertise their breeding territory. The cup nests are constructed of twigs and grass and include a mud layer to form a rather stiff and strong structure. Three to five eggs are a beautiful sky blue or turquoise color and as many as three broods may be produced in a season. Nestlings suffer significant mortality, with researchers reporting that only about 25% of young survive their first year. The longest reported lifespan from banding records is 14 years and in the wild Robins probably only live a few years. Predators on adult Robins include snakes, birds of prey, and other carnivores, such as raccoons. But domestic cats probably pose the most significant threat to Robins in a suburban environment.

American Robins are known to carry the West Nile virus. Because they are able to survive the virus longer than other birds that also are carriers, Robins may be responsible for greater infection of mosquitoes, which then transmit the virus to humans and other species.

James Taulman is a semi-retired research wildlife biologist, having worked with the U.S. Forest Service research branch and taught zoology, ecology, and other courses in several university positions. He lives in the East Mountains, and explores natural areas observing native wildlife and conducting independent research projects. Search for James Taulman on Youtube to see wildlife videos.