Species & Ecosystem Science

	Lead Scientist: Michael A. Schroeder Ecoregions: Columbia Plateau Ecological Systems: Inter-Mountain Basins Big Sagebrush Steppe, Inter-Mountains Basins Big Sagebrush Shrubland, Columbia Plateau Steppe and Grassland, Columbia Plateau Scabland Shrubland, Columbia Basin Foothill and Canyon Dry Grassland, Northern Rocky Mountain Lower Montane - Foothill and Valley Grassland, Northern Columbia Plateau Basalt Pothole Ponds, Columbia Basin Foothill Riparian Woodland and Shrubland
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	Two ruffed grouse chicks are attempting to cross a highway in western Washington. There are few data available for grouse populations, but there is clear evidence that many individuals die because of collisions on roads.
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	Cost-weighted distance map for sharp-tailed grouse in Washington and adjacent lands. The map illustrates the ease and extent of movement outward from habitat concentration areas.
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	Linkage map for sharp-tailed grouse in Washington. The map illustrates the least-cost corridor between adjacent habitat concentration areas.
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	Cost-weighted distance map for greater sage-grouse in Washington and adjacent lands. The map illustrates the ease and extent of movement outward from habitat concentration areas.
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	Linkage map for greater sage-grouse in Washington. The map illustrates the least-cost corridors between adjacent habitat concentration areas.

Grouse Ecology

Grouse and Landscape Connectivity

Project Description

Greater sage-grouse (Centrocercus urophasianus) and sharp-tailed grouse (Tympanuchus phasianellus) are native to large portions of the Columbia Basin in central and eastern Washington. The current ranges of both species are dramatically restricted to small portions of their historical distribution in the state (Schroeder et al. 2000). Sage-grouse and sharp-tailed grouse are landscape scale species that depend on extensive areas of suitable habitat to meet their annual requirements. Loss of connectivity within and between these areas can impede their ability to move between patches of suitable habitat with the potential consequences being: (1) fragmentation of populations; (2) reduced genetic heterogeneity; (3) localized extirpation; (4) susceptibility to the effects of climate change; and (5) reduced population viability.

The Washington Wildlife Habitat Connectivity Working Group (WHCWG) was formed to help incorporate wildlife habitat connectivity into revisions of WDFW’s Wildlife Action Plan and WSDOT’s transportation planning. Participants in the WHCWG include a wide range of agencies involved in natural resource management (state, federal, and tribal), non-governmental organizations, and academia. The mission statement of the WHCWG is “Promoting the long-term viability of wildlife populations in Washington State through a science-based, collaborative approach that identifies opportunities and priorities to conserve and restore habitat connectivity.” To accomplish this mission statement the WHCWG is addressing connectivity patterns at three scales: (1) statewide; (2) ecoregional; and (3) local.

The WHCWG Statewide Analysis was published in 2010 and examined connectivity at the statewide scale for a suite of 16 focal species. Greater sage-grouse and sharp-tailed grouse were two of the focal species included in this analysis. They were selected to represent the Semi-desert vegetation class in eastern Washington based on their use of expansive landscapes, and their sensitivity to alterations in the permeability of landscapes to movement. The statewide scale was addressed in 2010 and the ecoregional scale is currently being addressed for the Columbia Plateau.

Key Findings

• Habitat concentration areas for greater sage-grouse and sharp-tailed grouse tend to be situated at relatively high elevations, away from developed areas and high traffic-volume roads
• Habitats with high permeability (low resistance to movement) are relatively unfragmented, forming a loose configuration of native shrubsteppe.
• Cost-weighted distance and linkage maps show movement between habitat concentration areas in Washington for grouse is likely restricted.

What’s New

• Research is continuing on landscape connectivity including validation of assumptions and predictions of connectivity models using movement data from radio-marked greater sage-grouse.
• Testing connectivity models using patterns of greater sage-grouse lek persistence.
• Testing predictions of connectivity models using genetic data for greater sage-grouse.
• Statewide connectivity models for both greater sage-grouse and sharp-tailed grouse are being refined by: (1) increasing and improving the GIS data ‘layers’ used in the analyses of landscape resistance to movement and (2) concentrating the analyses on the Columbia Plateau Ecoregion.

Selected Publications

• Washington Connected Landscapes Project: Statewide Analysis

Staff

• Leslie A. Robb
• Andrew Shirk

All photos unless otherwise indicated are courtesy of Michael A. Schroeder