Of a Feather: Goodbye to the yellowhammers

By BILL CHAISSON
By Bill Chaisson

During migration you see unlikely birds in pedestrian places and likely birds in unlikely places. Last weekend it was impossibly bright and clear, so we decided to drive up the south side of Mount Kearsarge and look out at the changing foliage. At the summit I hoped to see some migrating raptors, but it was not to be. On the walk down, however, I spotted a large bird with a white rump churning off with an undulating flight and flashes of yellow: a northern flicker. On the drive down we saw another one start up from the side of the road and fly into the woods. The upper reaches of Mount Kearsarge are an odd place to see a bird normally associated with the lawn in your backyard.

The next day my sister described seeing five birds together that met the description of the northern flicker. It was a more usual location: the fields at the base of the Proctor Academy ski slopes in Andover. But five? That is when it belatedly occurred to me that these flickers were headed south.

The northern flicker (Colaptes auratus) is one of the few migrating woodpeckers. The other one in our region is the yellow-bellied sapsucker. Years ago, C. auratus was called the yellow-shafted flicker because it was thought to be separate from the red-shafted flicker (once called Colaptes cafer) of the West. The definition of species includes the proviso that members of a population will not regularly breed with another population and produce fertile offspring. The flicker does not meet this standard and fails in a color-coded fashion in a broad band between British Columbia and Alberta and south to Texas, where the ranges of the red- and yellow-shafted populations overlap and regularly produce hybrid birds.

The yellow shafts are visible on the underside of the wings on both the primary and secondary feathers and less visibly under the tail. Another regional difference is in the “mustache” or malar stripe of the males. It trails downward in an arc from the base of the slightly curved bill. In the eastern population it is black and in the western it is red. In the east both male and female flickers have a red crescent across the nape that western birds lack. A more subtle difference can be seen in the face, which is brown in eastern C. auratus and gray in western ones. Of course, in the Midwest you see birds with a mixture of all these characteristics. Roger Tory Peterson even describes birds with a red mustache on one side and a black one on the other.

C. auratus was officially called simply “flicker” until the 1957 5th edition of the “American Ornithological Union’s Checklist.” The red- and yellow-shafted names were used until 1983, when the 6th edition introduced northern flicker as a common name. As with the name “northern cardinal,” I always expect there to be a southern flicker as well, but there is not (as there is no “southern cardinal”).

There are, in fact, 14 recognized species of flicker (genus Colaptes) throughout the New World (with the one on Bermuda now extinct). Much haggling has taken place over the systematics of flickers based on their appearance, but molecular genetic studies are now settling matters in a quantitative fashion down to the subspecies level.

In 2016, Joseph Manthey of the University of Kansas, Lawrence and two other workers published “Relationships of morphological groups in the northern flicker superspecies complex (Colaptes auratus & C. chrysoides)” in the journal Systematics and Biodiversity. The latter species is the gilded flicker of the southwestern U.S.

According to Manthey et al., “Many species complexes have diversified rapidly and recently, resulting in morphologically diverse populations; however, the rapid pace of diversification often prevents identification of clear phylogeographic structure.” In other words, flickers have split into 13 different breeding populations (subspecies) relatively recently and abruptly, so it is difficult to tell how they are related to one another. Manthey et al. find five morphological groups, with the Guatemalan (mexicanoides) group being most genetically distinct from the rest.

In theory the local subspecies is C. auratus luteus, the northern population of the yellow-shafted form, but I found it impossible to find a description that distinguished it from C. auratus auratus, and you often see the name presented as auratus/luteus, which suggests the reliable differences are at the molecular level. “The Birds of New Hampshire” states unequivocally that auratus auratus is the local breeding form.

“The Birds of New Hampshire” further states that no C. auratus cafer forms have ever been seen in the state. I can report, however, that orange-shafted forms are found as far east as central New York. A friend posted a photo of a dead specimen on Facebook last year, looking for an identification.

We see fewer flickers around than we once did. They have declined by 49% since 1966, but this is thought to be at least in part a consequence of the reforestation of much of North America following the widespread abandonment of agricultural land. In addition, remaining agricultural land is farmed more intensively; hedgerows that once served as habitat have been removed.

In New Hampshire flickers are found all over the state but rarely seen above 2,000 feet, which made my Mount Kearsarge sightings notable. Unlike most woodpeckers, flickers feedly primarily on the ground and hunt for ants there. They peck at the soil as vigorously as other woodpeckers peck at wood, which would not work with frozen ground. Sapsuckers rely on eating insects caught in their sap wells, another non-starter in the winter. With these sorts of habits, you can see why they would both have to migrate south for the winter.

Bill Chaisson, who has been a birdwatcher since age 11, is a former editor of the Eagle Times. He now works for the Town of Wilmot and lives in Sutton.