Intergrade male Northern Flicker - Photo: Bob Boekelheide
Those Flashy Flickers
by Bob Boekelheide
November 2023
This month we give tribute to the amazing Northern Flicker, likely the most abundant woodpecker species in Clallam County. Without exception, on every Sequim-Dungeness Christmas Bird Count (SDCBC) since the SDCBC began in 1975, Northern Flicker has outnumbered all other woodpecker species combined.
Female Northern Flicker, red-shafted variety. Photo: Bob Boekelheide
Here is a graph (Figure 1) showing the number of Northern Flickers observed on the SDCBC over the last 30 years.
It really looks like flickers have increased on the SDCBC over the last 30 years. This is true even when corrected for our counting effort, by calculating the number of flickers seen per party hour. The number of flickers still shows an increase, although it doesn’t look quite as steep (Figure 2).
The number of flickers varies quite a bit between years, as shown by the sawtooth pattern moving above and below the regression line. Still, the overall increase is apparent. For example, prior to 2009 we never observed more than 200 flickers on a SDCBC, yet during 8 of the last 10 years (2013-2022) our count has surpassed 200 flickers. Have we become better at finding flickers? Not likely. Flickers are big, obvious, vocal woodpeckers, so I suspect the increase is real.
We know, however, that counting birds during a CBC is a bit of a crap shoot. Weather conditions and counters’ abilities vary every year. This is why it is so important to not place too much emphasis on changes between individual years. Long-term changes, like over 30 years, are much more meaningful, as shown by flickers.
Supporting our local observations, trend analyses from the Cornell Lab of Ornithology, as shown in their eBird Science section, also show increases in Northern Flickers in western Washington and along the West Coast of North America. Curiously, the same analyses show substantial decreases in flickers throughout many other areas of North America, including eastern WA.
Flickers are not particularly social, usually found singly, in pairs, or small groups. Flickers sometimes join together to form bigger flocks, perhaps dependent on food supplies or predators. The largest group I’ve seen locally was 25 flickers perched together in a big shrubby hedgerow in Jamestown on a cool fall day, possibly eating elderberries or some other fruits.
What time of year do we see the most flickers in the lowlands of the north Olympic Peninsula? Data from 21 years of Wednesday morning bird walks in Railroad Bridge Park show the annual cycle of flickers throughout the year. It is a clear pattern, with relatively few flickers during the nesting season from April to August, then rising to a peak in flicker abundance in October (Figure 3).
Where do the flickers seen in the Clallam lowlands in fall and winter go to nest in the spring and summer? A few flickers nest in the lowlands, but relatively few. It is likely that some flickers move upslope into the Olympic Mountain to nest, where they are abundant in open montane and subalpine forests during the nesting season. It is also likely that many flickers here in winter migrate north to nest in Canada and Alaska, where they nest as far north as the northern-most tree line.
This leads to an interesting story about flickers. There are three main “types” of flickers in North America – Yellow-shafted Flicker, Red-shafted Flicker, and Gilded Flicker. If you started birding before the 1980s, you remember when these three types were separate species. A watershed year occurred in 1982, when the American Ornithological Union lumped the three flicker species into only one species, the “Northern Flicker.” They did this because the three types freely hybridize and produce viable offspring (so why don’t they do this with large pink-legged gulls?). In 1995, the AOU partially reversed itself and decided that the Gilded Flicker, a desert flicker that typically nests in cacti, is unique enough to return to full species status, where it has been ever since.
Even though Yellow-shafted and Red-shafted Flickers now comprise separate subspecies within Northern Flicker, their geographic ranges are fairly distinct. The Yellow-shafted is mostly found east of the Rocky Mountains, whereas the Red-shafted is found in western North America down into Mexico. Where Yellow and Red-shafted types meet on the eastern slope of the Rockies, from Texas to Alaska, they produce “intergrades” that show variable characteristics originating from the two different subspecies. (Just to complicate matters, the term “intergrade” is used to designate crosses between subspecies, whereas the term “hybrid” designates crosses between full species.) One of the main intergrade zones lies north of us near the border between British Columbia and Alberta, the likely origin for many of the intergrade flickers we see in western WA during fall and winter.
The typical Yellow-shafted Flicker you see in eastern North America, other than having bright yellow wing linings and tail feathers, has a brown face, bluish-gray crown, and a red mark on its nape, on the back of its head. Yellow-shafted males have a black moustache, also known as a malar stripe. In contrast, the typical Red-shafted Flicker, other than having salmon-red wing and tail feathers, has a bluish-gray face, brown crown, and lacks the red mark on its nape (although some Red-shafteds nesting in western WA may occasionally show some red on the nape). Male Red-shafteds have a red moustache, or malar stripe. Pacific NW Red-shafted Flickers may have darker bluish-gray back and breast, in contrast to a brownish back and breast on Yellow-shafteds and other Red-shafteds.
Intergrade Northern Flickers combine characteristics from both parent subspecies, in a myriad of ways. They often have orangey wing and tail feathers, although these may range from yellow to red. They have variable face and crown colors, and may or may not have the red nape mark. Males have either red or black moustaches, sometimes both on the same bird.
Photo of intergrade male Northern Flicker #1, showing the red moustache and blue-gray face of a Red-shafted type, the red nape mark of a Yellow-shafted type, and orange wing shafts. Photo: Bob Boekelheide
Photo of intergrade male Northern Flicker #2, showing mostly red moustache with a hint of black in it, along with a brown face, bluish-gray crown, and large red nape mark of a Yellow-shafted type. Photo: Bob Boekelheide
Photo of intergrade male Northern Flicker #3, showing red and black in the moustache, brown face, bluish-gray crown and neck, very bluish-gray background colors on its back and breast, along with orange wing and tail shafts. Photo: Bob Boekelheide
Photo of a female intergrade Northern Flicker #4, showing the brown face and bluish-gray crown of a Yellow-shafted type, along with red wing and tail feather shafts of a Red-shafted type. Photo: Bob Boekelheide
It turns out the yellow, orange, and red colors found on flickers depend upon how the birds process carotenoid pigments from their diets. As the various pigments go through several metabolic pathways, the yellow feather colors arise from the least oxidation of the carotenoid pigments, the reddish colors have the most oxidation, and intergrade orange appears to be the result of incomplete oxidation when normal red pigment pathways are interrupted. It’s based on genetics, of course, which controls the biochemical pathways.
We live in an area with many intergrade flickers. Lucky us! Look closely at all the flickers you see this time of year and you’ll probably notice some flickers showing intergrade characteristics. The proportion of flickers listed as “intergrade flicker” on the SDCBC make up about two percent of all flicker sightings, but I suspect it might be higher than that.
Other research has shown that the intensity and saturation of flicker shaft colors, regardless of whether it is an intergrade or not, varies with the health of nestling flickers as they grow up in the nest. Healthy nestlings that fledge at higher body weights may show more intense coloration. Even the size of the black spots on their breasts varies with nestling mass, getting larger with higher body weights. The “blackness” of the bib on their breast may also be related to adult body condition and the age of the bird. Females with blacker bibs, likely older birds, laid eggs earlier, laid more eggs, and fledged more chicks. Their black tail bands may also enlarge with age, so that the chicks of older males with wider tail bands have higher fledging success. Feathers tell no lies, undoubtedly used by other flickers to determine the quality of potential mates.
Some Native American tribes are renowned for using flicker feathers in their regalia, particularly the Miwok and other tribes in California. The feathers are trimmed and sewn into strips, for use as spectacular head dresses.
Miwok flicker feather regalia at the Lava Beds National Monument museum. Photo: Bob Boekelheide
Flickers are master carvers, excavating nesting holes in as little as a week or two. The majority of flickers make their holes in dead trees, emphasizing the importance of leaving snags for wildlife. In actuality, many flicker pairs reuse old nest holes, so they may not excavate new holes every year. Their nest holes are not only used by flickers, but also by other species of birds and other animals. For example, the nesting distribution of the Bufflehead, the most abundant diving duck on the SDCBC, is mostly dependent on old abandoned flicker holes throughout the taiga forest.
Like many woodpeckers, flickers drum not only on trees, but also on houses and even metal, both as territorial gestures and possibly to attract mates. Woe be the homeowner if a flicker sets up shop pounding on the eaves or the siding of their house. A question frequently asked at the River Center in late winter and early spring is “How do I get rid of a flicker pounding on my house?” You can try to scare them away, but eventually they go away on their own, when either the hormones change or the bird migrates somewhere else. Draping the area with netting, hanging mylar tape, or somehow covering the area may help keep the bird away.
What do flickers eat? Their preferred prey during nesting is ants. Lots of ants. They carry ants to their chicks using a bulge in the front of their esophagus, similar to a crop. They eat other insects as well, including beetles, flies, termites, and bugs. They are unusual for a woodpecker because they forage mostly on the ground, where they ingest ants, other insects, and even seeds. Outside the nesting season they eat a variety of insects and fruits, including poison ivy and poison oak fruits. Around Sequim, they often gather in fall where there are fruits like elderberry and blackberry, but it’s hard to tell exactly what they’re eating. If you provide suet at your bird feeder, you know that flickers can demolish suet cakes in no time.
Flickers are renowned for having a relatively “fast” life history compared with other birds of similar body size, even compared with other woodpeckers. Flickers usually breed in their first year of life, they lay relatively large clutches averaging 6 to 8 eggs, and they don’t live as long as many other woodpeckers. Studies of banded flickers showed that less than half of the adults survive each year. Out of a sample of over 3000 banded flickers, the oldest male reached 10 years old and the oldest females only reached 9 years old. Life in the fast lane!
Your mission this month is to look closely at the flickers you see around the Olympic lowlands. What color are their wings and tails -- red, yellow, or orange? How and what are they eating? Are they alone or traveling with other flickers? How do they relate to other types of birds? We take flickers for granted because we see them so often, but there is so much to learn about flashy flickers.
Many of the interesting facts about flickers contained in this story came from Birds of the World, an on-line resource available through Cornell Lab of Ornithology. I highly recommend that all bird aficionados subscribe to Birds of the World, both for the information and to support the Lab of Ornithology.