We caught an interesting Northern Flicker this past week. Why did we think it was interesting? Well, take a look for yourself and see if you can figure out why:
Notice anything different/unusual about the wing?
Northern Flickers can be separated into two races. The Yellow-shafted Flicker, which is what we would expect to find here in the eastern part of the country, has, as it's name suggests, yellow feather shafts both in its remiges as well as in its rectrices. The male has a black 'mustache' as seen in this handsome fella below:
The Red-shafted Flicker, which occurs in the more western parts of our country, has, you guessed it, red shafts to its remiges and to its rectrices. The male Red-shafted Flicker has a red mustache instead of the black one that we see here in the east.
Yellow-shafted and Red-shafted Flickers can hybridize where their ranges overlap and, in fact, it is suspected that in some areas, all the flickers there are hybrids. A hybrid flicker can look pretty cool, in this bander's opinion. In the photos below you can see a hybrid male from Colorado that has the red mustache trait of the Red-shafted Flicker but completely yellow shafts on both its wings and tail. Pretty cool, huh?
Back to the original question though, can you see what is so cool about the flicker that we caught this past week? If you said that it has both red and yellow feather shafts, you would be correct! Now, what is so cool about this? Well, for a while, Yellow-shafted and Red-shafted Flickers were considered different species but then scientists realized that they were one in the same and that they frequently hybridized in their overlapping areas. But, for decades now, birds have been showing up far from the hybridization zone possessing both red and yellow feather shafts and there have been several hypotheses proposed over the years on why nearly 1/3 of the eastern population of flickers shows this characteristic. A few researchers, including Bob Mulvihill from the National Aviary, whom some of you might remember as having banded here in the past, had another idea in mind though: perhaps the pigment in their feathers was not a result of hybridization but rather, a result of their diet. Other species here in the east, such as Cedar Waxwings and Baltimore Orioles, have been documented to show orange feathers where yellow ones are usually the norm and so perhaps this was also the case with Yellow-shafted Flickers. Known sources of rhodoxanthin (the
carotenoid that produces that deep red hue in the feathers) are few in nature, especially in forms that birds can ingest but there is one in particular that flickers would have access to around here and that is found in the berries of the various non-native honeysuckle bushes that are now unfortunately quite common in the east. But flickers eat mainly ants and pupae you might argue, which is true, but in the fall they forage on berries and other fruits; they also moult their flight feathers in the fall. A coincidence? Probably not.
And, in fact, it was not a coincidence and the study results showing the link between red feathers in Yellow-shafted Flickers and their diet was published just this past fall. If you would like to read more about the study and the findings you can read it here.
