Process Description:
The Habitat Connectivity Investment Priorities layer provides high, medium, and low Safety and Ecological Stewardship habitat connectivity priority ranks for 1-mile highway segments. The ranks were derived from an analysis of base layer factors that occurred within ¼ mile of highway segments. The Safety rank base layer factors include, a union of the habitat ranges for deer, elk, moose, bighorn sheep, and black bear and the number of wildlife-vehicle collisions and carcass removals for these species. The Ecological Stewardship rank base layer factors include, a union of the habitat ranges of select Endangered Species Act (ESA) Federal listed endangered, threatened, or candidate species and ESA State listed endangered or threatened species, public land, Washington Habitat Connectivity Working Group’s landscape integrity layer, and estimated Average Annual Daily Traffic (AADT) counts. The base layers were created from a variety of GIS data sources. All of the base layers were projected to NAD 1983 HARN State Plane WA South (US feet), converted to polygons when needed, and clipped to the State boundary as necessary. Base layers were joined to highway segments that were buffered ¼ mile on both sides. Base layers that required additional processing are as follows: One mile highway segments centered on whole ARM values were created from WSDOT’s State Highway Log (2012). ARM values were entered in Excel spreadsheets and mapped using Display Route Events tool with 1:24K increasing state routes reference. The line segments were merged into one layer and buffered by ¼ mile on both sides. The public lands layer was created by merging DNR's ‘All Major Public Lands’ and ‘Federal Lands’ layers. All categories for ‘All Major Public Lands’ were selected except medical facility, public school lands, and incorporated city. The public lands layer was edited to remove areas that were already developed or had high potential for development. Public land polygons less than 5,000 acres in size were deleted. The remaining blocks of public lands were split by the state highways. After splitting, public land polygons that were less than 500 acres in size were deleted. Grizzly bear and gray wolf habitat ranges for the Ecological Stewardship rank were derived from the U.S. Forest Service Carnivore Landscape Permeability ‘Least Cost Analysis’ and ‘Potential Movement from Source Habitat’ layers. Grizzly bear range was a union of Habitat Concentration Areas, the best 50% least cost paths (1 through 5 levels) from the ‘Least Cost Analysis’ layer, and 100 km buffer (1 level) from the ‘Potential Movement from Source Habitat’ layer. Gray wolf range was a union of Habitat Concentration Areas, the best 30% least cost paths (1, 2, and 3 levels) from the ‘Least Cost Analysis’ layer, and 100 km buffer (1 level) from the ‘Potential Movement from Source Habitat’ layer. The gray wolf polygon was split by SR 97/SR 17 and the western polygon was used for Federal ESA listed habitat range. The entire polygon represents the State ESA listed range. Mazama pocket gopher habitat range for the Ecological Stewardship rank was created by digitizing polygons of known locations from WDFW's 2012 population surveys and suitable soils from NRCS for Thurston, Pierce, and Mason Counties. GAP distribution was used for Clallam County. Wildlife-vehicle collision and carcass removals for each species were summarized on the whole Accumulated Route Mileage (ARM) value for each highway segment. The frequency of vehicle collisions and carcass removals for each species were joined to the buffered highway segment layer using the unique identifier field, IDSRARM. AADT was derived from the 2011 Traffic Sections Estimated AADT layer. Increasing records were selected and exported to a new layer. The AADT polylines were spatially joined to the highway segment buffers.