Wildlife Management Institute: Early Removal of Invasive Conifers Essential to Habitat Restoration for Sage Grouse

View Full Size

Outdoor News Bulletin

Research led by The Nature Conservancy and released in mid-September validates efforts to limit the encroachment of juniper and other conifers in sagebrush habitats in order to maintain sage grouse populations, reports the Wildlife Management Institute. The report found that in the study area in eastern Oregon, there were no active sage grouse leks when conifer cover exceeded 4 percent within two-thirds of a mile of a lek location. The new study, that also assessed treatment costs, shows that proactive conservation efforts being undertaken through the Natural Resource Conservation Service’s (NRCS) can help to sustain populations of this bird that is teetering on the edge of being listed under the Endangered Species Act.

The Sage Grouse Initiative (SGI) was launched in 2010 after sage grouse were determined to be “candidates” for the Endangered Species Act. The decision marked the opportunity to engage in an aggressive effort to improve grouse habitat and populations to avoid a potential listing in the future. The vision behind the SGI has been to take the strength of the Farm Bill and its private lands conservation efforts and apply it to the 78 million acres in 11 western states where intact sagebrush habitats and the largest populations of the birds are found. While the initiative works on both public and private lands, about 40 percent of the best habitat is found on private lands. As a result, a majority of resources has been focused on providing technical support and Farm Bill funding to develop collaborative partnerships with local ranchers. NRCS has coordinated closely with the Intermountain West Joint Venture to provide the science and field capacity to support the effort.

Among the many habitat management strategies employed through the Sage Grouse Initiative, removal of juniper and other conifers that have encroached on western rangelands has been a top priority. In the Great Basin, conifers have expanded their range by 600 percent and now cover around 14 million acres; historically periodic fires prevented these conifers (predominantly juniper and pinyon pines) from spreading. The trees use significantly more water and outcompete bunchgrasses, forbs and sagebrush as they grow. This reduces forage for sage grouse as well as for livestock. In addition, the trees provide roost areas for avian predators. In Oregon alone, 875,000 acres of conifers are found within three miles of sage grouse leks. To combat this, the SGI has funded efforts to aggressively remove early phase invading conifers and has treated 200,000 acres of lands range wide in core habitats. A 5-minute video developed by the SGI explains the tree removal program and the advantages to landowners.

“Early tree removal is highly effective and less costly than a delay-and-repair approach that tries to turn a forest back into a sagebrush ecosystem again,” said Dr. Dave Naugle, SGI’s National Science Advisor at the University of Montana.

The new research that was funded by the SGI and released last month has now validated that targeted tree removal efforts are essential to successful conservation efforts. The study’s striking finding is that sage grouse populations vanish from leks at the low threshold of 4 percent tree cover. As a result, the scientists recommend prioritization of conifer removal efforts to areas with less than 10 percent canopy cover in an effort to get ahead of the rapid encroachment of conifer stands. In addition, the researchers were able to fine-tune recommendations and provide a “spatially explicit” plan for on-the-ground management in eastern Oregon. The study estimates that an annual investment of $8.75 million annually could address early encroachment on breeding habitat near all of the known Oregon leks in the next decade. Naugle goes on to say this new study gives confidence to partners involved in watershed scale tree removal that their investment is achieving the desired conservation outcome.

Like every other conservation effort that depends on federal government assistance and staffing, the Sage Grouse Initiative was placed on hold during the government shutdown. Until funds are fully restored and a Farm Bill is passed, the habitat restoration efforts will be hindered. These delays are particularly challenging in an initiative where an all out push for conservation and restoration is needed before 2015 when the U.S. Fish and Wildlife Service will reassess the sage grouse’s candidate status.(jas)