Close, But Not Identical
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When I volunteer at the Arizona-Sonoran Desert Museum or when I hike over at Sabino Canyon I frequently encounter visitors from out of state who point out a bird and who comment that it looks like a cardinal but is somewhat unusual in appearance. Invariably, they are pointing at a Pyrrhuloxia, a species of cardinal that is closely related to, but that is an entirely different species than the Northern Cardinal.
Visitors often confuse male Pyrrhuloxias, such as the bird shown above, with female Northern Cardinals like the one shown directly below. There is obviously more than a superficial resemblance.
Neither bird is all red, both have brilliant red crests, and both have wedge-shaped bills. But, there are differences well, and once one knows the differences, the birds are usually easy to tell apart. A male Pyrrhuloxia has brilliant red feathers on its face, breast, outer wings, and tail. The rest of the bird is slate gray-colored. Its bill is ivory-colored and there is definite curvature to the upper part.
By contrast, a female Cardinal has no red on her face, her body is rust-colored, and her bill is reddish in tone and is much more wedge-shaped than is the Pyrrhuloxia’s bill.
Of course, male Northern Cardinals are brilliant red except for their faces (black) and are not easily confused with any other bird. Finally, female Pyrrhuloxias, such as the one in the final image, are almost completely gray with the exception of a few red feathers on their crests and tails. In my opinion they don’t look at all like female Northern Cardinals.
Both species seem to occupy the same ecological niche in this part of the country. They live side by side and they appear to eat much the same diet. It’s interesting to speculate how two so closely related species evolved in the same habitat. Did one species descend from the other? Or, do they have a common ancestor? I’m just guessing and I could be totally wrong but I suspect that the Northern Cardinals are a more recent arrival to the area inasmuch as the species is essentially a species that inhabits the non-desert precincts of the eastern United States. In other words, Pyrrhuloxias may have evolved as desert specialists whereas cardinals may have evolved elsewhere, moved in, and adapted to the local habitat. But, that’s a wild guess on my part and I freely admit that I could be totally wrong.
Photos taken with a Canon 5Diii, 400 DO + 1.4X Extender, aperture preferred and “M” settings, ISOs varied, f stops and exposures varied.