A bright flash of reddish-orange explodes from a tree trunk- a Northern Flicker taking flight.
In the Pacific Northwest, the red-shafted Northern flicker is the most common while in the eastern United States, the yellow-shafted Northern Flicker is common.
Red-shafted vs yellow-shafted Northern Flickers
The key differences between red-shafted and yellow-shafted Northern Flickers:
Red-shafted flicker
- Gray face
- Brown crown
- No nape (back of neck) crescent
- Red mustache stripe on males
- Rosy-red flight feather shafts
- Salmon-pink underside of wing and tail feathers
Yellow-shafted flicker
- Tan face
- Gray crown
- Red nape crescent
- Black mustache stripe on males
- Lemon-yellow flight feather shafts
- Bright yellow underside of wing and tail feathers
Yellow- and red-shafted Northern Flickers are almost genetically identical except for 0.01% of their genome (the genetic material of an organism). Scientist Stephanie Aguillon of the Cornell Lab of Ornithology sequenced the entire genome and found that those few differing genes account for the difference in feather coloration.
At least six Northern Flickers regularly visit my suet feeders. At first I thought they all looked the same. However, upon closer inspection I started to notice slight differences.
I noticed the difference between the male and female red-shafted flickers- the male with the red mustache and the female without.
Then I noticed one with a few splotches of red on its nape- a hybrid!
Hybrid Northern Flickers
In 1843, John James Audubon found a flicker nest hole along the Missouri River with five birds- a mix of red- and yellow-shafted. At the time he didn’t know he was in the hybrid zone which is roughly along the Rocky Mountains.
There is a wide overlap zone where the red- and yellow-shafted Northern Flickers interbred extensively.
The hybrids look intermediate with some characteristics of both. One variation is the coloration of a red-shafted Northern Flicker with the addition of a red crescent on the nape.
Why are Northern Flicker feathers red, yellow and orange?
Northern Flickers feather coloration is based on carotenoids. They are the only bird in North America that deposits carotenoids in the feather shaft according to Dr. Jay McEntee at Missouri State University. The carotenoids make the feathers bright red, orange and yellow.
Additional feather color variations
The observation of yellow-shafted Northern Flickers with varying orange and red feather shafts in the eastern US had ornithologists wondering if the hybrid zone was expanding.
Research by Jocelyn Hudson, curator of ornithology at the Royal Alberta Museum, worked with colleagues to show that those intermediate hues of red and orange plumage were due to the pigment rhodoxanthin- a pigment found in exotic honeysuckle berries the birds were consuming.
The pigment is different than the 4-keto-carotenoids that give the red-shafted flickers their coloration. Therefore, the color differences were due to diet and not genetics.
Have you seen any hybrid Northern Flickers?
Resources
- Genome sequencing: https://www.allaboutbirds.org/news/its-official-red-shafted-and-yellow-shafted-flickers-have-nearly-identical-dna/
- Genome sequencing: https://www.newsweek.com/invasive-berry-turning-birds-feathers-red-509005
- Feather color: http://springfieldmn.blogspot.com/2020/10/the-case-of-yellow-feathers.html
- Northern Flickers: https://www.allaboutbirds.org/guide/Northern_Flicker/overview
