While the eastern population of Purple Finches has declined significantly since the invasion of House Finches (a few California individuals released from a pet store in New York City in 1939 as well as natural expansion of its western range resulted in a population explosion of House Finches in the east), both species can appear at feeders. Without fail, every winter I have to relearn the field marks that distinguish these two birds. Both males and females of these respective species are quite similar, but it is the drab and sparrow-like females that send me flying to a field guide.
Three features stand out as most helpful in distinguishing female Purple Finches from House Finches. The female Purple Finch has short, dark streaks on her breast, whereas the House Finch’s breast streaks are quite blurry. The female (and male) Purple Finch has a distinctly notched tail; the House Finch’s tail is just slightly notched. Finally, and most obvious, are their respective head patterns. Female Purple Finches have a conspicuous light eyebrow stripe that contrasts with a solid, dark brown ear patch, both of which the House Finch lacks.
Being seed eaters, Purple Finches are attracted to sunflower seed feeders, and if you feed birds, this provides ample opportunity to observe these field marks. While doing so, you may notice that Purple Finches can be fairly aggressive with each other when vying for this source of food. Surprisingly, more often than not, the female prevails. (photo: female Purple Finch)
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