American robin

thumb|Video of a male robin singing

thumb|American robin song (with a [[black-capped chickadee in background)]]

The American robin (Turdus migratorius) is a migratory bird of the true thrush genus and Turdidae, the wider thrush family. It is named after the European robin because of its reddish-orange breast, though the two species are not closely related, with the European robin belonging to the Old World flycatcher family. The American robin is widely distributed throughout North America, wintering from southern Canada to central Mexico and along the Pacific coast.

According to the Partners in Flight database (2019), the American robin is the most abundant landbird in North America (with 370million individuals), ahead of red-winged blackbirds, introduced European starlings, mourning doves and house finches. It has seven subspecies.

The species is active mostly during the day and assembles in large flocks at night. Its diet consists of invertebrates (such as beetle grubs, earthworms, and caterpillars), fruits, and berries. It is one of the earliest bird species to lay its eggs, beginning to breed shortly after returning to its summer range from its winter range. The robin's nest consists of long coarse grass, twigs, paper, and feathers and is smeared with mud and often cushioned with grass or other soft materials. It is among the earliest birds to sing at dawn, and its song consists of several discrete units that are repeated.

The adult's main predator is the domestic cat; other predators include hawks and snakes. When feeding in flocks, it can be vigilant, watching other birds for reactions to predators. Brown-headed cowbirds (Molothrus ater) lay their eggs in robin nests (see brood parasite), but the robins usually reject the egg.

Taxonomy

This species was first described in 1766 by Carl Linnaeus in the twelfth edition of his Systema Naturae as Turdus migratorius. The binomial name derives from two Latin words: ', "thrush", and ' from ' "to migrate". The term ' for this species has been recorded since at least 1703. confirming a 2007 study which also placed this as its closest relative. Though having distinct plumage, the two species are similar in vocalization and behavior.

Subspecies

Seven subspecies are accepted. These, except for the isolated T. m. confinis, intergrade with each other and are only weakly defined.

T. m. nigrideus breeds from coastal northern Quebec to Labrador and Newfoundland and winters from southern Newfoundland south through most of the eastern U.S. states to southern Louisiana, southern Mississippi, and northern Georgia. It is uniformly darker or blackish on the head, with a dark gray back. The underparts are slightly richer red than those of the nominate subspecies. but both the American Ornithologists' Union and the IOC World Bird List regard it as only a subspecies, albeit in a different group from the other six subspecies. Among standard measurements, the wing chord is , the culmen is and the tarsus is . The head varies from jet black to gray, with white eye arcs and white supercilia. The throat is white with black streaks, and the belly and undertail coverts are white. The adult has a brown back and a reddish-orange breast, varying from a rich red maroon to peachy orange. While robins occasionally overwinter in the northern part of the United States and southern Canada,

The species is a rare vagrant to western Europe, where the majority of records have been in Great Britain, where 29 had been recorded up to the end of 2022. The species has occurred as a vagrant to Greenland, Sweden, Jamaica, Hispaniola, Puerto Rico and Belize. Vagrants to Europe, where identified to subspecies, are the eastern subspecies (T. m. migratorius), but the Greenland birds included the Newfoundland subspecies (T. m. nigrideus), and some of the southern overshots may have been the southern subspecies (T. m. achrusterus).

A successful West Nile virus vaccine has been administered to six 3-5 week old American robins. A DNA vaccine injected intramuscularly resulted in a 400-fold decrease in average viral load that would likely make robins noninfectious and unable to spread disease. An oral bait is the preferred method of distribution of the vaccine as it would be easier and cheaper than intramuscular injection, but more research would be needed as the existing formulation did not work orally.

Behavior

The American robin is active mostly during the day, and on its winter grounds, it assembles in large flocks at night to roost in trees in secluded swamps or dense vegetation. The flocks break up during the day when the birds feed on fruits and berries in smaller groups. During the summer, males defend a breeding territory and are less social. Due to their insectivorous and frugivorous diet they have evolved to lose sucrase. It is frequently seen running across lawns picking up earthworms, and its running and stopping behavior is a distinguishing characteristic. In addition to hunting visually, it also has the ability to hunt by hearing. Experiments have shown that it can find earthworms underground by simply using its listening skills. Canids such as foxes and dogs take fledglings from the ground. Raccoons often prey upon nests, while small agile carnivores such as American martens, ring-tailed cats and long-tailed weasels hunt adults. The greatest predatory impact is probably from raptorial birds. 28 raptorial bird species hunt American robins. Adult robins are most vulnerable while breeding activities, whereas feeding flocks are vigilant for predators. In a study of 105 juvenile robins, 77.1% were infected with endoparasites, Syngamus sp. being the most commonly encountered, in 57.1% of the birds.

Breeding

thumb|With nest-making materials

Breeding begins shortly after the returning to the summer range. The species is one of the first North American birds to lay eggs, and normally has two to three broods per breeding season, which lasts from April to July.

A clutch consists of three to five cyan-colored eggs, and is incubated by the female alone. The eggs hatch after 14 days, and the chicks leave the nest a further two weeks later. The altricial chicks are naked and have their eyes closed for the first few days after hatching.

The chicks are fed earthworms, insects, and berries. Waste accumulation does not occur in the nest because the adults collect and take it away. Chicks are fed, and then raise tails for elimination of waste, a solid white clump that is collected by a parent prior to flying off. All chicks in the brood leave the nest within two days of each other. Juveniles become capable of sustained flight two weeks after fledging. Chicks become sexually mature at one year of age. Bird banders have found that only 25% of young robins survive their first year. The longest known lifespan of an American robin in the wild is 14 years; the average lifespan is about two years. The song varies regionally, and its style varies by the time of day. The song period is from late February or early March to late July or early August; some birds, particularly in the east, sing occasionally into September or later. They are often among the first songbirds to sing as dawn rises or hours before, and last as evening sets in. It usually sings from a high perch in a tree. It was depicted on the 1986 Birds of Canada series Canadian $2 note (this note was subsequently withdrawn.) It has a place in Native American mythology. The story of how the robin got its red breast by fanning the dying flames of a campfire to save a Native American man and a boy is similar to those that surround the European robin. The Tlingit people of northwestern North America held it to be a culture hero created by Raven to please the people with its song. The Peace Bridge robins were a family of American robins that attracted minor publicity in the mid-1930s for their prominent nest on the Canadian side of the Peace Bridge connecting Buffalo, New York, to Fort Erie, Ontario.

American popular songs featuring this bird include "When the Red, Red Robin (Comes Bob, Bob, Bobbin' Along)", written by Harry M. Woods. Although the comic book superhero Robin was inspired by an N. C. Wyeth illustration of Robin Hood, a later version had his mother nicknaming him Robin because he was born on the first day of spring.

The species is considered a symbol of spring. A well-known example is a poem by Emily Dickinson titled "I Dreaded That First Robin So". Among other 19th-century poems about the first robin of spring is "The First Robin" by William Henry Drummond, which, according to the author's wife, is based on a Quebec superstition that whoever sees the first robin of spring will have good luck. The association has continued down to the present day, as, for example, in one Calvin and Hobbes cartoon from 1990 that had Calvin celebrating his inevitable wealth and fame after seeing the first robin of spring. The harbinger of spring sobriquet is borne out by the fact that American robins tend to follow the average temperature isotherm north in spring, but also south in fall. In a study of 209 psychology students at the University of California, Berkeley, Eleanor Rosch found that the robin was, in the students' minds, the most prototypical example of a bird (though the students did not have the opportunity to specify the species of robin). Robin egg blue is a color named after the color of the bird's eggs.

Gallery

File:American-Robin-New-York-April-2022.png|alt=A fluffed up American Robin standing by a tree surrounded by dandelions and grass|Fluffed-up American robin

File:Robin eating a worm in spring.jpg|Eating an earthworm

File:American Robin with a worm.jpg|Male carrying an earthworm

File:American Robin 20140512.jpg|Perching in a tree

File:American Robin Eating Crabapples Durango CO 2-19-2019.jpg|Feeding on crab apples

File:Robin's Nest - Charlotte NC.jpg|Newly hatched chick among unhatched young

File:Turdus migratorius MWNH 1784.JPG|Eggs, Collection Museum Wiesbaden

File:Juvenile robin (12336).jpg|Juvenile in New York

File:Robin eggs flying in 3 weeks - by Volkan Yuksel.jpg|Sequence of dated images showing the progress from eggs to fledging in three weeks

File:Robin chick 2 Galawebdesign.jpg|Chick

File:American Robin Nest.jpg|Nest amidst human habitat

</gallery>

References

External links

FieldGuide – eNature.com
"Robins of a Different Feather" – albinism in robins
Animal Facts – natural history, maps, and photos at the Washington Nature Mapping Program
Vocalizations – Journey North
Sound file – vivanatura.org
Plans for nesting shelves – Journey North
Nesting journal – Photo blog following the process from nest building to leaving the nest – Webster's Wobbins
Florida bird sounds including the American robin – Florida Museum of Natural History
American robin subspecies Turdus migratorius nigrideus (Aldrich and Nutt)
American robin growth progress with date stamp