Recent Study: 'Strong link' Between Grouse Breeding Grounds, Private Lands



September 19, 2014 (E&E Greenwire Report) - A strong majority of sage grouse breeding grounds in the West are found within a short distance of stream sides, wet meadows and irrigated fields that are mostly privately owned, according to a new federally funded study released this week.

Those wetter lowlands -- which provide critical flowering forbs (broad-leaved plants) and insects that help feed growing chicks after they hatch -- represent 2 percent of land in the arid West, but more than 80 percent of the lands is in private hands, the study said.

The study underscores the importance of private land conservation in staving off an Endangered Species Act listing for sage grouse next September, while helping federal and state officials identify the best places to conserve, researchers said.

The study, published by the Sage Grouse Initiative, a partnership led by the Natural Resources Conservation Service, found that 85 percent of breeding grounds, known as leks, were clustered within 6 miles of these wet summer habitats.

And while about 80 percent of the uplands that sage grouse use for nesting are located on public lands, about 80 percent of the lowlands where they raise their broods are private, said Dave Naugle, a study co-author who is science adviser to SGI.

"Birds are not just setting up leks to access nesting areas, but also to make sure that places where they raise their young are nearby," he said.

The study covered 32 million acres of sage grouse range in California, Oregon and northwestern Nevada, and tapped data from annual lek surveys collected by the states and Landsat satellite imagery. Scientists studied location and male population counts for 1,277 active lek sites in relation to habitat cover observed from the sky.

The study was led by Patrick Donnelly, a landscape ecologist with the Fish and Wildlife Service, with assistance from Naugle, Jeremy Maestas of SGI and Christian Hagen of Oregon State University.

Western ranchers have long known that they own the lion's share of the valley bottoms that are vital part of the sage grouse life cycle. European settlers to the Great Basin knew these areas that collected snowmelt were the most fertile and stayed wet longer into the summer. They were typically the first lands to be claimed.

The Fish and Wildlife Service in 2010 found the greater sage grouse warranted listing because its habitat was increasingly degraded and fragmented by agricultural conversion, urbanization, roads, power lines, more frequent wildfire, invasive plants, grazing and energy development. The agency faces a court-ordered deadline of September 2015 to decide whether to propose permanent protections for the bird.

Naugle said the study is the first to map the distance between popular leks and wet meadows.

Wetter lowlands can include natural sites like riparian areas, seasonal wetlands, lakes and playas (shallow basins) with moist vegetation, or they can be developed agricultural sites including wet meadows and alfalfa fields. More than 92 percent of the wet meadows in the study were irrigated.

In July and August, when sage grouse chicks are mere puff balls, flowering forbs and insects help the birds gain muscle, bones and feathers, Naugle said.

The leks with the highest densities of breeding birds were within 1.8 miles of wet meadows, the study found.

"In other words, the scarcity of wet habitats in sagebrush ecosystems drive the location of grouse breeding sites on uplands: hens choose to mate and nest within a reasonable walk of where they can find late summer foraging for their broods," the study said. The data "reveals a strong link between wet sites, which are essential summer habitat for sage grouse to raise their broods, and the distribution of sage grouse breeding areas or leks."

A further walk to wet meadows can stress hens and chicks and expose them to a greater risk of predation, the study found.

During droughts, when natural wetlands and meadows may dry out, privately irrigated pastures become even more crucial to the next generation of chicks, the study said,

Naugle said NRCS is already using data from the study to pinpoint the best private lands to secure conservation easements along the California-Nevada border to preserve the bi-state population of sage grouse. Fish and Wildlife must decide whether to finalize its threatened listing for that subpopulation in April 2015, and conservation easements funded by NRCS will be a crucial factor in its decision.

The Obama administration this summer announced that the Agriculture Department, which includes NRCS, will commit $25.5 million over the next five to 10 years "to accelerate and focus" ongoing conservation efforts and partnerships with ranchers in both states to preserve the bi-state population.

Naugle said FWS, BLM and the Forest Service have tasked Donnelly to expand the wetlands mapping tool he developed in this week's three-state study to the greater sage grouse's 11-state range to assist state and federal planners. It should be available within a year, he said.

While most of the remaining sage grouse habitat is on Bureau of Land Management and Forest Service lands, more than 30 percent of it is private.

And though preservation of leks has been a top focus for federal officials, this week's study underscores the need for a broad conservation strategy.

"The lek site is simply the dance floor," Luke Schafer, the West Slope advocacy director for Conservation Colorado, said last spring during a lek tour in northwest Colorado. "It's the habitat within 4 miles of that lek that matters."

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