Greater Sage-Grouse

By David Cronenwett

“Remember that the yield of a hard country is a love deeper than a fat and easy land inspires, that throughout the arid West the Americans have found a secret treasure…a stern and desolate country, a high bare country, a country brimming with a beauty not to be found elsewhere.” – Bernard DeVoto 1943

There are still places in Montana where the increasingly rare Greater Sage-Grouse (Centrocercus urophasianus) can be observed. The bird’s story and precipitous decline is intimately tied to its shrub-steppe habitat which, like most non-forested landscapes, has suffered greatly at our hands. The species’ mating ritual is highly stylized, occurring each spring typically in open areas with sparse vegetation. Males compete with one another in an elaborate dance to establish mating dominance; feathers fanned with yellow air sacs on their breasts inflated, the birds swagger about producing a variety of strange coos, pops and chortles, occasionally battling one another in the process. Females will observe these strutting displays, often for several days before deciding whom to copulate with.

Sage grouse are big, weighing up to seven pounds which makes them the largest grouse in North America. One might suspect that a bird of this size would not be a strong flier. Though they do spend a great deal of their time foraging on the ground, single flights up to six miles at speeds approaching fifty miles per hour have been recorded. Some populations will remain in the same range year round, but others seasonally migrate. The longest known movements occur when birds from southern Alberta and Saskatchewan travel over 100 miles into Montana in autumn using a “hopscotch” approach; alternately walking and flying as it suits them.

As its name implies, this animal is strongly tied to sagebrush habitats. Because they do not possess a muscular gizzard for grinding tough seed-foods, their diet is limited almost entirely to softer vegetation. As such, sage grouse evolved a strong preference for the leaves of our many species of sagebrush (Artemesia spp.) which accounts for 62% of the annual diet and 99% of the winter diet. Very few creatures can thrive off of Artemesia which possess mildly toxic terpenes (aromatic hydrocarbons) in their tissues.

It would be difficult to find an ecotype that suffers from greater distain in our culture than sagelands. The shrub-steppe habitat, defined by a predominance of sagebrush species, superficially appears monotonous, uninteresting and desolate to many people. Upon closer inspection, one discovers a diverse ecology that changes in complexity depending on elevation, topography and annual moisture. A mosaic of shrubs, native grasses and forbs support a great variety of animal life. This enormous body of country covering portions of eleven western states including Montana, has been poetically dubbed by its advocates, The Sagebrush Sea. In Montana, this ecotype can be found in the southwest, southcentral and Missouri Breaks regions. Like prairies however (and for many of the same reasons), sagelands have been viewed largely as suitable only for energy development, intensive grazing, industrial recreation and agriculture. But this is slowly changing as new environmental concerns emerge. Since the correlation between the decline of sagelands and the grouse is rather direct, the bird is now considered an ecological barometer for the health of its larger habitat. Population estimates range from approximately 16 million across the West a century ago to about 200,000 to 500,000 at present with further declines predicted. For perspective, the historical expanse of the Sagebrush Sea was about 270 million acres. It is now approximately 150 million.

Besides conversion to agriculture and poor grazing practices, sage grouse and their habitat suffer from multiple problems. Invasive plant species, particularly cheatgrass (Bromus spp.) has altered the fire regime and species composition in some areas, making habitat unusable for grouse and most native wildlife. Collisions with fences are a significant vector of mortality for the birds, though this can be remedied by using devices to make top wires more visible. Energy development like oil and gas drilling displaces these sensitive birds outright. Another issue; any sort of structure more than a few feet above the ground attracts perching raptors, which unnaturally increases predation on sage grouse. This means housing developments, gas rigs, power lines, and even native conifers that move into sagelands because of fire suppression can increase mortality.

The Greater Sage-Grouse is considered a Species of Concern by the state of Montana. The federal government has reviewed a potential listing under the Endangered Species Act (ESA) and a decision is likely to be made in 2015. To say that such a designation would change human activity on the sagelands is a remarkable understatement, a fact well understood by most stakeholders. Because of this, an unprecedented wave of collaboration is occurring. This past spring, Montana governor Steve Bullock initiated a multi-stakeholder advisory council to address conservation of this species. Janet Ellis, program Director for Montana Audubon, is an appointed member of this Council, and a draft recommendation will be out later in October, with public meetings in November and public comment accepted through November 30, 2013.  Stay tuned — we’ll need your voice.

At a regional scale, the Sage Grouse Initiative, a partnership of ranchers, agencies, nonprofit groups and business interests was launched in 2010 by the Natural Resources and Conservation Service (NRCS). The idea is to improve conditions so an Endangered Species Act listing is not necessary, and this is being done by developing local conservation practices in sage country to protect and in some cases restore the ecosystem, including its ‘flagship’ animal the Greater Sage-Grouse. With many changes, both positive and negative occurring in sage country now, the future of the bird and its habitat will likely become clear before long.