The Bellowing Bird That Could
The dancing, popping, whistling sage grouse just may help save the best of its arid western habitat
The final topic last November at a conference on sage grouse did not seem at first to be all that controversial: Should the speakers produce a book based on the talks they had just delivered-with observations on the bird's strutting, bellowing mating dance and details of its habitat requirements in the West's sagebrush lands? Probably not, most said at first. After all, much of the material could be found in the scientific literature-if a person just took the time to look for it.
But then wildlife biologist Erick Campbell interrupted to urge the speakers to consider the federal Bureau of Land Management (BLM) workers who make most of the decisions that affect the birds. "A manager in the field is not going to be able to go to the literature just to look up sage grouse." said Campbell. "You've got a guy who's got goshawks; he's got bull trout; he's got range management and surveys he can't keep up with. He's in a place like Battle Mountain, Nevada. He's up to his keester in environmental assessments and piles of journals. His library doesn't even have Time magazine."
The gathering of 50 scientists and land managers was electrified, and Campbell wasn't even finished. He stood up from his chair. "We're seeing changing times, and this is an opportunity," hesaid. "We're going to see ecosystem reform." The group's surprise was not so much at Campbell's message, a common theme in public-land debates these days, but at the messenger. For Campbell is himself with the BLM in Portland, Oregon. Although the BLM supervises most sage grouse habitat-a mix of brush and grasses known as shrubsteppe-the agency has traditionally managed its resources for livestock, not wildlife.
For decades, the BLM's shrubsteppe has been plowed, burned, sprayed and chained to plant grass-and then has been grazed, mostly by cattle. Says BLM biologist Alan Sands of Boise, Idaho, "We are finally moving away from an attitude that all sagebrush is bad." In the early 1880s, the West held perhaps 90 million acres of prime sage grouse habitat. Today, the BLM is that habitat's single largest manager, with 30 million acres. And only three percent of the agency's total 170 million western acres-so predominantly leased for private livestock grazing that they are commonly called rangeland-is in pristine condition.
So, despite the fact that the BLM funded this meeting-conceptualized and arranged by the nonprofit High Desert Ecological Research Institute in Bend, Oregon-Campbell's plea was an astonishment. After he sat back down, the 18 speakers relented. As long as land managers wanted the book, they would write it after all. Still, its bottom line will be no surprise. "This isn't rocket science," says biologist Clait Braun, wildlife research leader of the Colorado Division of Wildlife. "Birds need habitat."
No other creatures are more intimately tied to shrubsteppe than sage grouse, which require a mosaic of the landscape's plants and features for survival, mating, nesting and brooding. The more scientists have discovered about those needs, the more the birds' presence appears to be a key indicator that their habitat supports a diverse plant and animal community. Says Mike Crouse, BLM chief of biological resources for Oregon and Washington, "If you're providing for the various needs in the life cycle of sage grouse, you've probably got healthy range."
Shrubsteppe's wildlife includes pronghorn, elk, mule deer, pygmy rabbits, burrowing owls, kit foxes, leopard lizards, neotropical migratory birds, raptors like ferruginous hawks and prairie falcons-and the list goes on. The plant community boasts a variety of forbs and grasses, and spring can bring a spectacular floral display.
But for all its diversity, shrubsteppe has never had the popular appeal of, say, old-growth forest. Says BLM biologist Jon Sadowski of Vale, Oregon, "The only time most people see shrubsteppe is from Interstate 80 while going 70 miles an hour in the summer. Until you come out when the thing is expressing itself with a flourish, you can't appreciate it." Adds Mike Collopy of the National Biological Survey Unit in Corvallis, Oregon, "It's open country; you can see the wildlife, the sunsets. You've got the whole big-sky thing. It's remarkable."
The message from sage grouse, then, is sobering. The birds once populated at least 15 western states; now they are found in only 12. Overall counts are not available, but biologists agree that the birds' numbers are plummeting. In Colorado, for example, the number of counties with populations of sage grouse has gone from 27 to 15, and the average number of males per mating ground has decreased from about 55 in the early 1950s to fewer than 25 now.
According to the Western States Sage Grouse Technical Committee, a coalition of states and Canadian provinces in the species' historic range, sage grouse distribution and abundance has markedly decreased. "There's no doubt they're reduced by at least half," says Colorado's Braun, past chairman of the technical committee. A recent survey found that biologists at 43 of all the 76 BLM field resource areas with sage grouse report a long-term decline of the birds.
For public-land managers, the combination of this bird's decline and what it means about the ecosystem sounds unsettlingly familiar. When other high-profile indicator species in the West have been federally listed as threatened or endangered in recent years, the consequences have been painful. "Here in Oregon," says BLM's Crouse, "I personally lived through about five years of listing of spotted owls and marbled murrelets and salmon. And in each case, there were contentious environments and an incredible amount of hardship. Now sage grouse have come up on the radar screen. We don't have a clear picture yet of their status, but if there's anything we've learned, we can't go on managing one species at a time."
In other words, if the sage grouse has what ecologist David Dobkin, director of the High Desert Ecological Research Institute, calls "the potential to become the, spotted owl of the shrubsteppe," the BLM wants to do things differently this time. How? By managing with "more of a landscape perspective," says Crouse.
And sage grouse are serving as a guide to that perspective. Take the plants, from familiar clover to lesser-known hawks-beard, milkvetch, goatsbeard, fescue and needlegrass. Recent research led by biologist John Crawford of Oregon State University has found that nesting hens and chicks use all of those and many more as food and cover from predators like golden eagles and coyotes. "Nearly all cover types we looked at are important for sage grouse," says Crawford.
Still, at the heart of the bird's habitat requirements is sagebrush. From fall through winter, sage grouse eat only sagebrush leaves, moving as snow accumulates to areas where the plant is still accessible: windswept ridges or drainages and draws packed with tall, dense bushes. The birds may use only 10 percent of their habitat in winter, but the right 10 percent must be available.
Sagebrush contains substances that most animals' digestive systems can't tolerate. Rather than grind food in their gizzards, sage grouse eat large amounts of forage, actually consuming only the small amount that is highly digestible. The birds also then pass some of the material into caeca, sacs where bacteria further break down the food. Eventually, the caeca eject undigestible compounds in a tarry ball, a telltale field sign of the birds, which also deposit dry pellets.
Sage grouse do so well on their sage brush diet that they reach peak weight in time for the rigors of spring mating. That's when the males establish leks, gathering on fairly open plots of land from February to early June to attract females. Early every morning, the males perform highly ritualized displays that include strutting, noise-making and opening their tail feathers. The morning timing is no coincidence; that's when foraging females are likely to critique the males' performances. "If the males were displaying at a time when females were sitting under a bush detoxifying sagebrush they had eaten, the males would never get anywhere," says behaviorist Jack Bradbury of the University of California-San Diego.
To make their distinctive sounds, the males inflate and then squeeze air sacs in their chests. Out come a pop, a whistle and another pop. To the casual human observer, it's a single "plop." To the sage grouse, says Bradbury, "the duration of the inter-pop interval and whistle seems to be the primary factor in choosing a male." For all the males' efforts, only one or two busy suitors in the displaying group are usually rewarded by all the females. Says behaviorist Robert Gibson of the University of California-Los Angeles, "The big issue is: What are the females getting?" The answer seems to be that no matter what attributes the hens may select, they end up with males that show extraordinary stamina.
For land managers, lekking behavior offers two lessons. One is that the birds need escape cover right next to their strutting grounds for quick getaways from predators. The other is that the birds apparently do not establish leks on habitat edges. Why? Bradbury and Gibson have found that the females first spread out to forage, and then the maleschoose lekking grounds in the center of that foraging area. "Sage grouse males are mapping on the females that are mapping on the resources," says Bradbury. So females need rewarding habitat before males will lek among them-and presumably, habitat altered near an established lek could strongly affect the birds.
Perhaps nowhere do all these observations have more relevance than in Colorado's Gunnison Basin, home of a unique and beleaguered population of sage grouse. These birds differ in many ways from others of the species. For one thing, the males' strutting noises are much lower, "like boiling water," says Jessica Young, a Ph.D. candidate at Purdue University. And they pop their air sacs nine times in two seconds rather than twice. During their display, the Gunnison birds also throw their more developed neck feathers over their heads and uncharacteristically shake their tails.
The 3,000 Gunnison birds likely comprise a southeastern subspecies that has dwindled to this final group. Throughout the basin, roads, power lines and subdivisions have infringed on habitat. Range "improvements" and grazing have eliminated much ground cover needed for nesting. And now the Department of Energy (DOE) is dumping mill tailing waste in a pit on BLM land in the middle of sage grouse habitat. "Within half a kilometer of the pit, you could throw a softball to where at least one quarter of all the basin's mating males breed," says Young.
Young and the Colorado Division of Wildlife's Braun, among others, have objected to the dumping of toxic wastes in the sensitive area and related disturbances. The BLM maintains in written responses that it used a "very thorough analysis process" to decide that "we can allow the relocation of the uranium mill tailings while adequately mitigating adverse impacts to sage grouse habitat." But the very researchers who have most studied the birds (funded in part by BLM) are among those objecting.
Is this the same agency that sponsored last fall's sage grouse conference-which included as speakers some of the same scientists who object to the DOE's Gunnison plans? Yes and no. The agency has long been "politically driven," as BLM biologist Sands points out. Perhaps in this case, as in the larger question of grazing reform that has lately been making headlines, the politics of the Clinton Administration's new notion of ecosystem reform are battling politics of old-which traditionally, says ecologist Dobkin, "have traded the biological integrity of the resource for short-term economic gain."
Meanwhile, there is still plenty of hope that lessons from the sage grouse about the definition of healthy shrub-steppe will, says Dobkin, "chart a different pathway from that taken for management of the spotted owl." And in the process, perhaps the sage grouse will become an indicator species for the BLM as well as for the shrubsteppe.
Senior editor Lisa Drew attended the High Desert Ecological Research Institute's sage grouse conference for this article.
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