Window on Nature
By Lowell & Kaye Christie, F47246
February 2007
If you’ve traveled across the United States, you’ve probably seen the “Sagebrush Sea.” Sagebrush grows in eastern Washington and Oregon, most of Nevada, across southern Idaho and Wyoming, and in isolated areas in Utah and Colorado. With it covering so much territory, it was interesting to discover that nearly all varieties of sagebrush are endemic, meaning they grow nowhere else in the world.
Sagebrush thrives where the winters are long, the summers are hot and dry, and the wind blows no matter the season.
Of course, a broad range of altitudes and varied amounts of rainfall are found in an area as large as the Sagebrush Sea. The plant grows in elevations ranging from sea level to 12,000 feet, with much of it around 4,000 feet. Combine that with rainfall of around eight inches a year, and it’s not surprising that this country is called “high desert.”
Sagebrush Sea is an apt nickname. We’ve driven through many areas where nothing but sagebrush was in view. Talk about wide open spaces.
But the Sagebrush Sea is shrinking. Currently it covers approximately 150 million acres; 150 years ago, sagebrush covered an area twice that size. Extensive clearing for crops and pasturelands turned the wasteland into fertile farmland and livestock range.
Still, wildlife is abundant in sagebrush country. Bighorn sheep roam there. Pronghorns race over open ground. You might meet up with coyotes, rabbits, raccoons, and even porcupines. Getting a look at a bobcat or mountain lion is less likely, but they live there, too.
More than 200 species of birds thrive in these wide open spaces, but one deserves special mention: the sage grouse. These are really big birds, which can measure more than two feet long from the tip of their beaks to the end of their sharply pointed tails.
And as the name implies, the range of the sage grouse correlates quite well with that of the Sagebrush Sea. It’s no accident, given that a sage grouse’s diet is heavily dependent upon sagebrush nibblings. From fall through spring, the leaves and stems of sagebrush make up more than 90 percent of their diet. And since a mature sagebrush plant can produce as many as a million seeds, the birds down them as well. In fact, the sage grouse is so dependent on sagebrush that they’re often referred to as “sagebrush obligates,” creatures that can’t survive where their namesake plant doesn’t grow.
If you’ve traveled within their range, it’s entirely possible you’ve heard sage grouse, even if you haven’t seen them. A sage grouse’s voice will certainly catch your attention, as its rapid “kek . . . kek . . . kek . . .” is hard to ignore. That’s how we got our first sighting.
During mating season, sage grouse males gather at “leks,” or courtship assembly areas. Leks come in various sizes, ranging anywhere from a single acre to 40 times that amount. At dawn and at dusk, sage grouse cocks march around, spreading their tails to make the long, sharply pointed feathers spread out to form a prickly black fan.
To further encourage the females, courting males rapidly flap their wings to inflate and deflate air sacks on their necks, producing a loud, bubbling, “pop, pop, pop” sound. The females are attracted by the noise and activity and gradually move close enough to view the competing males strutting around. Oddly, most females mate only with the dominant male.
But it really doesn’t matter which male they choose, because, when mating season passes, the males take off, leaving the hens to tend to the eggs and raise their young. Fortunately, newly hatched sage grouse chicks stand up and walk as soon as they peck their way out of the egg. That frees the mother to scurry around finding food for her fast-growing chicks.
The sage grouse and sagebrush are perfect examples of how habitat and animal life adapt to each other over the centuries. Perhaps it was best expressed by Rachel Carson in her book Silent Spring. In it, she wrote: “The sage and the grouse seem made for each other. The original range of the bird coincided with the range of the sage, and as the sagelands have been reduced, so the populations of grouse have dwindled. The sage is all things to these birds of the plains. The low sage of the foothill ranges shelters their nests and their young; the denser growths are loafing and roosting areas; at all times the sage provides the staple food of the grouse. Yet it’s a two-way relationship. The spectacular courtship displays of the cocks help loosen the soil beneath and around the sage, aiding invasion by grasses which grow in the shelter of sagebrush.”
The next time you are driving across this open Sagebrush Sea, stop for a bit and take a walk. Feel the wind as it blows across the open landscape. It may seem desolate at first glance, but it is really filled with life. Check it out and see if you don’t agree.
For more insights about the natural world around us, visit the Christies’ Web site, www.OurWindowOnNature.com. Here you will find more stories and observations about the birds and butterflies, mountains and deserts, and many of the other outdoor wonders the couple has discovered during their travels.