Red-tailed hawk

Start with what we do not know. On an August evening near the Roosevelt cabins in Yellowstone, we watched a hawk take an American pika, stand over it on the ground until it finished eating, and then lift off carrying what was left. We could not see enough to name the bird. This page is not a record of that hawk. It is a page about the species most likely to have been it, and the difference matters enough to say twice.

A red-tailed hawk is a buteo, which is the shape you already picture when someone says hawk: broad rounded wings, a short wide tail, long slow circles over open ground. The wings span about four feet and the whole bird weighs one and a half to four pounds, less than a housecat. Adults carry a reddish-brown tail, which is the one field mark worth trusting, because the rest of the bird is unreliable. Red-tailed hawks come in colors from dark brown to nearly white, and a young one has a banded brown tail instead of a red one. Ours, whatever it was, never showed us its tail.

It hunts on the ground. About nine of every ten things a red-tailed hawk eats is a rodent, and the rest is rabbits, snakes, ground squirrels, and birds that spend their time low. Grand Canyon National Park describes the pattern we watched without knowing it: a big kill gets eaten where it happened, and a small one gets carried off to a perch. Yellowstone’s own page on pikas lists hawks among their predators, next to coyotes and martens, and puts the pikas you are most likely to see in the Mammoth and Tower areas. Roosevelt is in the Tower area, in talus country, which is why the odds line up the way they do.

In Yellowstone the park bird checklist marks the red-tailed hawk as a confirmed breeder, common in spring and fall and abundant in summer. Between 2011 and 2015 the park’s raptor study counted at least 60 red-tailed hawk territories on the northern range, tightest on the Blacktail Deer Plateau, and found that breeding success there averaged below what a stable population needs. Sixty territories on one stretch of country still means that a hawk over the sagebrush north of the Grand Loop is, on the numbers, most often this one.

You have heard one, whether or not you have seen one. The National Park Service points out that the hoarse scream in almost every western is a red-tailed hawk, dubbed over whatever raptor the camera happened to find, bald eagles included. That is the sound most people expect a hawk to make, and it is a poor way to name one. The safer method with a hawk over Yellowstone is to watch for the tail, wait until the bird turns, and be willing to write down “hawk” if it never does.