There are several species of birds that are difficult to distinguish from one another. For me, the House Finch (Carpodacus mexicanus) and the Purple Finch (Carpodacus purpureus) fall into this category.
Above you see the male House Finch. Note the long, square-tipped tail, the red breast, forehead and stripe over the eye. Note also the dark streaks on his side and flanks. Click on photos for full sized images.
The female House Finch below has more obvious streaking on her belly and flanks and you can see streaking on her undertail coverts as well, however her face pattern is fairly plain.
Here are photos of two different male and female House Finches
Notice that there is some variance of color and pattern between the four individuals, but they still have the same field marks.
Now let’s take a look at the male Purple Finch. He is kind of a raspberry red, the brightest red on the head and chest (and his rump if you could see it). However, the easiest field marks you don’t see are the streaky flanks and undertail coverts. Look ma, no streaks!
And notice that the streaking on the female Purple Finch, unlike on the female House Finch, pretty much disappears on the lower belly and undertail coverts. She does, however, have some facial markings that make her stand out in a crowd. The broad light stripe behind her eye and her dark ear patch distinguish her from the plain headed House Finch.
The Purple Finches also have a more deeply notched tails than the House Finches. You can see the more distinct markings on the female and the more overall purple coloring on the male in the photo below. Seeing the female’s light facial striping is always my first clue that I have Purple Finches visiting my yard, not the male’s coloring.
As Pete Dunn describes the difference between these two species in his book, Pete Dunne’s Essential Field Guide Companion, “House Finch looks like it had wine thrown in its face; Purple Finch was dipped in it.”
In this two and a half minute video of the finches battling at the sunflower seed tube feeder, you will see a female Purple Finch come into the middle of the feeder at about the 50 second mark. You will see why this is always my first alert to their presence. She sticks out like a sore thumb.
There are no male Purple Finches in this video but you may notice the spunky little Pine Siskin that defends its lower perch throughout the entire video! A female Lesser Goldfinch comes in near then end and makes a brief appearance also.
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