In my last posting, I mentioned photographing a few Purple Finches. Of those photos, I've chosen to display this image of a male and female Purple Finch because it beautifully demonstrates what it means to say a bird species is "dimorphic" (meaning the sexes are different in appearance). Of course, many other bird species are "monomorphic" or similar in appearance, but today let's look at the example of the Purple Finch--a dimorphic species.
When learning to identify birds, I made the mistake that all new birders (and even seasoned birders) sometimes make--trying to identify the female of some dimorphic species as a different species all together. Looking at these two seed-loving finches, you can easily understand why. Having happily identified his/her first Purple Finch (who looks more cranberry-colored to me), the new birder might easily become mystified when a week later encountering a streaked brown and buff bird.
"Must be some kind of sparrow" was most likely my response when first spying the female Purple Finch. And why not?
I ask you this: Does the female have purple (or cranberry) plumage? No. And yet the species is named after the more colorful male. No wonder it's easy to get confused. Ha!
So whenever you see a brilliantly-colored male, look around for his less showy mate. The species you've identified just might be dimorphic.
Till next time . . . Keep birds in your heart!
Georgia Anne Butler
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