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would help those of us without formal training in the (significantly changed over recent years) systematic names!
Only have hazy memories of seeing red winged blackbirds but thought they usually had more red on the wing and sometimes a bit of yellow, is there variation across USA in this?
I've never yet been to the Americas, so I have no personal experience of these, but your "hazy memories" are correct.
There are numerous described races/subspecies of Red-winged Blackbird, and most have more red in the wing with a band of yellow along the lower edge.
Five races, found in California which ties in with the location given for this observation (and also parts of Mexico) lack the yellow border - and are sometimes known as 'Bicoloured Blackbird'
Very interesting Roy.
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