Tehachapi News

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I often get asked to identify local birds, especially raptors, in absentia: “I saw a big dark bird last week in a tree near my house, and it wasn’t a raven, so  what was it?” is the typical sort of question. Most of the time, the unknown bird was an example of our most common and widespread bird of prey — the Red-tailed Hawk (Buteo jamaicensis).

There is a simple reason why Redtails are so frequently the source of confusion: they show more variation in plumage than any other raptor, and possibly any other bird of any kind in North America. They range from very pale individuals (even white, in the case of rare albinos) to very dark chocolate brown birds, with many gradients in between.

The typical Redtail seen perched atop a power pole or oak tree, waiting for a small mammal to appear, is a large bird (20 inches tall with a 4-foot wingspan) with a dark hood, light chest, streaked belly and dark wings with mottled light markings and highlights.

In the West, however, darker birds referred to as either dark or intermediate morphs may make up 10 to 20 percent of the population at any given time. You only have a 1-in-10 chance of seeing fully dark red-tailed hawks, however.

The dark morph birds are strikingly handsome, with an overall rich brown coloration. Juveniles have light and dark banded tails and yellow irises, while birds 2 years or older have dark eyes and the distinctive red tail for which the species is named. Even the darkest individuals still have white markings on the outer half of their underwings.

Although the name “morph” suggests that these color patterns can change, they are not phases and a dark morph bird will remain a dark morph bird its entire life, even though birds replace their feathers every year. Whether they are light, intermediate or dark morph birds, they will retain the same coloration even after they molt.

The coloring of Redtails is analogous to that of gray wolves — while most wolves are the typical overall gray with light bellies and some dark markings, individuals may range from entirely white to completely black, and even littermates may be different colors.

Though color variations seem to have no impact on either mate selection or the prey that Redtails hunt, there is some evidence that lighter birds tend to choose more open areas to nest and darker birds tend to select darker, more shaded nest sites with more cover.

Pay attention as you travel in the Tehachapi area and sooner or later you will see dark morph red-tailed hawks. Along Highline Road, Banducci Road, Cummings Valley Road, throughout the rural areas, even in town the observant resident can spot these ubiquitous raptors patiently waiting on tall perches for something edible to make an appearance.

Once in awhile, the bird you see will be a beautiful dark chocolate brown and you’ll know you’ve seen the equivalent of a black wolf on the prowl.

Have a good week.