OREGON STATE UNIVERSITY

Despite lack of listing, sage grouse remains in decline

03/05/2010

CORVALLIS, Ore. – After several decades of concern over widespread population declines, the U.S. Interior Department opted today to not pursue listing the western sage grouse as endangered under the Endangered Species Act. Instead the grouse will be added to a list of species being considered candidates for federal protection.

Estimates for the decline of sage grouse populations across much of the West range from 17 to 47 percent and are associated with the loss of sagebrush-dominated ecosystems, researchers say. Today’s decision leaves the protection and restoration of this habitat largely in the hands of state agencies and organizations.

To reduce losses to the grouse population it is necessary to protect the habitat upon which it depends for food, nesting sites and protection from predators, said Richard Miller, a professor of rangeland ecology and management at Oregon State University.

The grouse, which in appearance most resembles a cross between a peacock and a chicken, has a range that covers areas east of the Rocky Mountains and two distinct western sagebrush ecosystems: the sagebrush steppe and the Great Basin sagebrush. Miller has been working in both ecosystems studying the impact of different land management strategies on sagebrush, and the species that depend on it, for more than 20 years.

“The sagebrush steppe is one of the most endangered ecosystems in North America,” said Miller, who is part of Oregon’s Sage-grouse Conservation Steering Committee. “It is threatened by invasive weeds of which there are estimated to be more than 19 million acres of cheat grass alone; overgrazing or poor grazing management; cultivation; development for urban and infrastructure, including energy infrastructure and roads; fire suppression and wildfire; and at the higher elevations the invasion and encroachment of pinion and juniper.”

In general, areas most suitable for sage grouse habitat and conservation are characterized by cold wet winters, dry hot summers and variable topography. Tree cover is often minimal, however low growing shrubs and grasses are prevalent.

Within these fragile ecosystems the grouse are subject to habitat fragmentation, predation, and an increasing risk of fatal disease – specifically West Nile Virus for which the birds have zero tolerance.

“West Nile could literally and totally wipe out the entire species,” said Miller. “It is a catastrophic disease for the population.”

In terms of management there is little that can be done about the spread of the mosquito-borne West Nile in the sage grouse population, said Miller. However, management can have a large impact on the sagebrush steppe, and that in turn increases the odds for the survivability of the sage grouse.

Miller outlines three stages to managing the ecosystem for the benefit of the birds:

  • Identify and maintain those areas that are already in good shape and supporting healthy populations;
  • Restore areas that can be restored, using native plants where appropriate;
  • In the highly arid areas that often can not be restored to a natural state capable of supporting grouse populations, focus on developing new research techniques and technologies to increase the likelihood of successful restoration.