American Robin

The American Robin is one of the best-known birds and a common sight across North America – the quintessential birds of garden lawns and parks where they can be seen searching for earthworms. One of the first birds to arrive in spring the American Robin is a member of the Thrush family and was given its name by early settlers, who thought that, with its reddish breast, it resembled the English Robin. American Robins breed north to Alaska, across Canada, and southward to the coast of the Gulf of Mexico in the United States and into southern Mexico.

Adult Male (spring/summer)

Nape and upper back dark gray / blackish, darker head with white eye crescents and dark tail showing white corners in flight. Bill yellow often with a black tip. Breast, belly red. Vent and undertail coverts white.

Adult Female (spring/summer)

Duller gray upperparts with duller reddish/orange breast and paler head. Whitish belly with dark tail showing white corners in flight. Bill yellow often with black tip.

Juvenile 

Large black breast spots with pale supercilium and duller, pinkish bill. Recent fledglings show prominent gape and natal down giving them a wispy, downy appearance.

General:

Large and sturdy with round body, long legs and fairly long tail. Length: 25cm. Wing: 43cm. Weight: 77grams.

Behaviour:

Watch an American Robin strut across a lawn. Notice how it takes several steps, then adopts an alert, upright stance with its breast held forward. When landing they habitually flick their tails.

Habitat:

Although common in gardens, parks and residential areas they are also at home in wilderness areas and mountain forests and are found in most habitat types except marshes preferring open areas in winter.

Information:

Many American Robins spend the whole winter in their breeding range but spend more time roosting in trees so are less visible. These winter roosts can include as many as 250,000 birds and are a way to protect against predators and to locate feeding areas.
The American Robin has an extendible esophagus for storing fruit allowing the robin to survive low nighttime temperatures during the winter months. Fruit is a major part of the birds diet at this time of the year.
Migrating American Robins are not nocturnal migrants like many songbirds but travel during the day. They begin their northward movement in late February arriving in Canada in early March. Temperature is a key factor in their migration, for the birds need soft ground in order to dig for earthworms.

American Robins can produce three successful broods in one year but research has shown that on average only 40 percent of nests successfully produce young – of those only about 25 percent survive to November and only about half of those will make it to the next meaning that the entire population turns over on average every six years!

The longevity record for American Robin is 13 years and 11 months.

Similar species: ​

Varied Thrush, Spotted Towhee.​​​​​​​​​​​​​​​​​​​​​​​​​​​​

Conservation Status:

Populations appear to be stable or increasing throughout range. Because the robin forages largely on lawns, it is vulnerable to predation from domestic cats and pesticide poisoning but unlike many species, the American Robin has adapted well to habitat disturbance adapting to urbanization. Deforestation, the growth of urban areas, and the increase in farmland have all contributed to the breeding habitat for this bird.

Capture Rates

Usually a short-distance migrant, American Robin can remain in the Lower Mainland through the winter depending on local weather conditions. They are among the first species to return to their breeding grounds as seen by the spike in capture rate in March then again in June – August when young are dispersing. If American Robins do remain over the winter however, they are usually seen not extremely active and congregating at large roost sites high up in trees as suggested by our zero capture rates between November – February.

Molt Summary:

PF: HY partial, PB: AHY complete; PA absent

Preformative molt includes some to all med covs, 0 – 9 inner gr covs, and sometimes 1 – 2 terts, but no rects.

Tail shape should always be used with caution due to individual variation and the possibility of accidental loss and replacement (called adventitious molt).

The tail of the HY bird above is showing very fresh and quite rounded rectrices but notice the sharp ‘dagger’ points to the very tips of the outer rectrices.

This SY in March is showing replaced median coverts, two replaced inner greater coverts (GC 9 & 10 red arrow) and 8 retained outer greater coverts with buffy fringes to the terminal edges. These buffy fringes often form the classic ‘tear drop’ shape at the end of the rachis a common pattern in thrushes.

A close up of the coverts of this SY male in April clearly shows the replaced median coverts, two replaced inner greater coverts (red arrow) and the noticeable ‘step-in’ between them and the 8 retained outer greater coverts again showing the buffy tear drops to the terminal edges. Notice the difference in structure and wear between the replaced and retained greater coverts and the washed out, brownish rachises of the visible remiges (primaries and secondaries) versus the glossy black rachises of the remiges of the adult birds below.

This SY female in April also shows the typical pattern of tear drops to the retained 8 outer greater coverts with the replaced 2 inner greater coverts (red arrow) again showing the ‘step-in’ between replaced and retained feathers.

This ASY male in April is a prime example of what definitive adult plumage, with no discernible molt limits among the coverts or alula, looks like in spring. Note the uniform appearance of all wing feathers, the broad, truncate shape of the primary coverts and broad, grey edging to these feathers and to the adjacent greater coverts. Note also the broad, truncate shape of the visible remiges (primaries and secondaries) and the thick, glossy black rachises (shafts) of these feathers and compare with the first year birds above.

The tail of the ASY male in April above is showing broad, truncate shape to the outer rectrices and a corner to the inner web of these feathers and glossy, black rachises.

This AHY in June is already undergoing its definitive adult prebasic molt and is likely an SY female based on the contrast between replaced and as yet unmolted feathers and brownish versus blackish remiges.

The adult prebasic molt starts with the proximal lesser and median coverts, then tertials and innermost primaries (primary coverts molt with the corresponding primaries); greater coverts molt shortly after the start of the primaries which is the stage that this bird has reached.

Note the broad, truncate shape of the replaced primaries and primary coverts and the glossy, black rachises compared to the as yet unmolted primaries, primary coverts and secondaries.