American Robin
Turdus migratorius
The eastern subspecies (T. m. migratorius) is 23 to 28 cm (9.1 to 11.0 in) long with a wingspan ranging from 31 to 41 cm (12 to 16 in), with similar size ranges across all subspecies. The species averages about 77 g (2.7 oz) in weight, with males ranging from 72 to 94 g (2.5 to 3.3 oz) and females ranging from 59 to 91 g (2.1 to 3.2 oz). Among standard measurements, the wing chord is 11.5 to 14.5 cm (4.5 to 5.7 in), the culmen is 1.8 to 2.2 cm (0.71 to 0.87 in) and the tarsus is 2.9 to 3.3 cm (1.1 to 1.3 in). The head varies from jet black to gray, with white eye arcs and white supercilia. Voice: The male, as with many thrushes, has a complex and almost continuous song. It is commonly described as a cheery carol, made up of discrete units, often repeated, and spliced together into a string with brief pauses in between. The song varies regionally, and its style varies by the time of day.
ID text from Wikipedia, CC BY-SA 4.0
Common Blackbird
Turdus merula
In Europe, the common blackbird can be confused with the paler-winged first-winter ring ouzel (Turdus torquatus) or the superficially similar common starling (Sturnus vulgaris). A number of similar Turdus thrushes exist far outside the range of the common blackbird, for example the South American Chiguanco thrush (Turdus chiguanco). The Indian blackbird (Turdus simillimus), the Tibetan blackbird (Turdus maximus), and the Chinese blackbird (Turdus mandarinus) were formerly treated as subspecies of the common blackbird. The common blackbird of the nominate subspecies T. m. merula is 23. Voice: In its native range in the Northern Hemisphere, the first-year male common blackbird of the nominate race may start singing as early as late January in fine weather in order to establish a territory. This is followed in late March by the adult male.
ID text from Wikipedia, CC BY-SA 4.0
Where you might meet both
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