I usually see dark-eyed juncos in winter, and a lot of the time in flocks. They are my favorite sparrow, because I like the combination of black and white.
Most juncos migrate to Canada, and in the winter come to the United States and Mexico. Some stay in the U.S. year-round. Those that stay have shorter wings, and the ones that migrate have longer wings. The ones who migrate have bigger wings because it helps with long flights. Some other birds have shorter & longer wings for the same reason.
The difference between a female and male dark-eyed junco is that the male is more likely to have a black hood. The female is typically lighter than the male, with more grey and brown. Females almost never have black.
Females make the nests out of typical nesting materials—moss, twigs, grass, etc. They use their body to shape the nest.
Dark-eyed juncos are very common. The estimated population is 630,000,000 individuals!
My Birding Year 
Nice post, Jack!
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Thanks!
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Jack, I don’t believe we have this sparrow here in the winter, although we have others. I also really like the black and white, so I will keep an eye out for them. Do you think they usually winter in New Mexico?
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Yes they do winter in New Mexico, and live in most of the state year-round.
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Alida–it’s worth noting that there is a LOT of variety among these juncos, though. Some have quite a bit more color, and some are more drab or black-and-white. Here are a few of the varieties.
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