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Sure about that bird ID? Maybe it’s just dyed!!

Northern Flicker - Colaptes auratus

This is a red-shafted Northern Flicker, found in central South Dakota. One tell-tale characteristic…the reddish color visible here under the tail. The gray face, and red “mustache” are also characteristic of the red-shafted color phase. Scientists have found that thanks to pigments within berries of invasive honeysuckles, some yellow-shafted flickers found in the eastern United States are in effect dying their own plumage through their diet, confusing birders who spot reddish-tinged birds.

A cool story that explains some odd-looking birds that you may come across!  South Dakota is in the middle of the country as far as “western” and “eastern” birds are concerned.  That’s great from a birding perspective, as we can often encounter species from both sides of the continent. Northern Flickers are a species that can be seen across the state, but given our geographic location, the “red-shafted” color phase (with salmon coloring under their wings) is the kind most often seen in the western part of the state, while the “yellow-shafted” (yellow underwings) is the one most often seen in the eastern part of the state.   Besides the color under their wings and tail, head markings and facial colors also differ between the two color phases.  Throughout the state, you may see intermediate phase birds, with characteristics of both phases.

A new study finds a confounding factor for identifying red-shafted vs. yellow-shafted Northern Flickers. In the eastern U.S., birders have sometimes spotted Northern Flickers with curiously reddish underwings and plumage.  Up until now, the assumption had been that some of the genetic make-up of the western red-shafted flickers must have been finding its way into the eastern U.S.  However, this study found that the issue isn’t genetics, but an invasive plant!

There are two species of an invasive honeysuckle that produce berries with reddish pigment.  This new research finds that “reddish” birds in the eastern U.S. don’t have the genetic components of red-shafted flickers, but instead have high levels of pigment from ingested honeysuckle berries.  In effect, the birds are dying their own plumage if their diet includes the invasive berries!

As the story notes, it’s not just Northern Flickers, but also Cedar Waxwings that sometimes have odd plumages due to the honeysuckle pigments. It’s another great example how a human influence, and the introduction of invasive species, can interact with native species in ways we can’t even imagine.

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