Flickers

I’ve been noticing some small holes in our lawn lately. The holes are about the size of a dime and go down at an angle for about an inch. I recently discovered they were caused by one of our common woodpeckers, the northern flicker. Many of you know the bird as the yellow shafted flicker.

Flickers are woodpeckers, but unlike their relatives, prefer feeding on the ground. Ants are among their favorites, but I’m guessing these excavations are from the birds feeding on white grubs. White grubs are the larvae of June beetles, and are often found in Kentucky bluegrass sod.

Not long ago, scientists recognized two closely related species of flickers in North America. The yellow shafted flicker ranged over much of the continent east of the Rockies while the red shafted flicker was found roughly from the Rockies westward. As you might expect, the yellow shafted flicker ranged over much of North Dakota, but the red shafted flicker occupied western portions of the state, particularly southwest of the Missouri River.

The two species were similar, but had some obvious differences in coloring. However, some flickers with characteristics of both species were found where the ranges overlapped, such as along the eastern edge of the Rockies. These birds were assumed to be hybrids.

Some biologists began to question whether the flickers were, in fact, two species. It subsequently became evident that they were not separate species: They readily interbred and produced fertile offspring. Scientists now recognize the “northern flicker” as one species that has two color forms. If you have an old bird book at home, it will likely have the old designations. Most recently published books have made the correction.

Our concept of a species is changing. Research is helping us better understand the dynamics of a species; how they evolve, mechanisms influencing reproduction (and reproductive isolation), and other related aspects. Regardless of their classification, I’m still going to enjoy watching the flickers feeding in our yard, and muse over how a species, and our understanding of a species, evolve.

Chuck Lura

Natural North Dakota is supported by NDSU Central Grasslands Research Extension Center and Minot State University-Bottineau, and by the members of Prairie Public. Thanks to Sunny 101.9 in Bottineau for their recording services.