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Research about Selawik National Wildlife Refuge

Source-linked reports with geographic coverage including Selawik National Wildlife Refuge.

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Development of a digital land cover data base for the Selawik National Wildlife Refuge

Digital land cover and terrain data of the Selawik National Wildlife Refuge were produced by the U.S. Geological Survey's (USGS) Earth Resources Observation Systems Alaska Field Office for the U.S. Fish and Wildlife Service. These and other environmental data were incorporated into a Fish and Wildlife Service geographic information system to prepare a comprehensive conservation plan and an environmental impact statement for the refuge and to assist in research and management of the refuge. The digital data base, stored on tapes, includes land cover classifications from Landsat multispectral scanner data, elevation, slope, and aspect data for the area covered by the USGS Selawik and Shungnak l:250,000-scale topographic maps. The maps incorporate more than 90 percent of the refuge. Additional digital data in the data base include (a) land cover of the entire refuge at 50-, 200-, and 400-m pixel sizes derived from Landsat multispectral scanner data; (b) Landsat multispectral scanner data registered to a 50-m Universal Transverse Mercator grid; (c) elevation, slope, aspect, and solar illumination data registered to each Landsat scene; (d) stream hydrography and surficial geology digitized from USGS l:250,000-scale quadrangle maps; and (e) Refuge and wilderness boundaries. In addition to the digital products, color hard copy maps were produced from the l:250,000-scale quadrangle base land cover, elevation, slope, and aspect digital data.

Alaska

Selawik National Wildlife Refuge land cover mapping project users guide

Title III of the Alaska National Interest Lands Conservation Act (ANILCA, 1980) established the Selawik National Wildlife Refuge (SNWR). Section 304 of the Act requires the Secretary of Interior to "prepare, and from time to time revise, a comprehensive conservation plan" for the refuge. Before developing a plan for the refuge, the Secretary shall "identify and describe--a) the populations and habitats of the fish and wildlife resources of the refuge; b) the special values of the refuge as well as any other archeological, cultural, ecological, geological, historical, palentological, scenic, or wilderness value of the refuge; c) areas within the refuge that are suitable for use as administrative sites or visitor facilities...; d) present the potential requirements for access with respect to the refuge...; and e) significant problems which may adversely affect the populations and habitats of fish and wildlife identified and described..." (ANILCA, 1980). Vegetation, water, and terrain (elevation, slope, and aspect) are the components of habitat and can be used in the determination of the above requirements. The U.S. Fish & Wildlife Service (USFWS) has the responsibility for collecting the resource information to address the research, management, development and planning requirements identified in Section 304. Because of the brief period provided by the Act for data collection, habitat mapping, and habitat assessment, the USFWS in cooperation with the U.S. Geological Survey's EROS Field Office, used digital Landsat multispectral scanner (MSS) data and digital terrain data to produce land cover and terrain maps. A computer assisted digital analysis of Landsat MSS data was used because coverage by aerial photographs was incomplete for the refuge and because the level of detail obtained from Landsat data was adequate to meet most USFWS research, management and planning needs. Relative cost and time requirements were also factors in the decision to use the digital analysis approach.

Alaska