Use of U.S. Fish and Wildlife Service Easements for the South Dakota GAP Stewardship Layer Dorthy M. Dateo, Michael
E. Estey, Kenneth F. Higgins, Jonathan A. Jenks, and Rex
R. Johnson Over the past five years, the Cooperative Fish and Wildlife Research Unit and the Department of Wildlife and Fisheries Sciences at South Dakota State University have been involved in research projects that relate directly to Gap Analysis. Geographic information systems have been or are being developed for wetland basins in eastern South Dakota and bird and amphibian distributions (Johnson and Higgins 1997; Naugle; Bakker; Fischer unpubl. data). In addition to these data, wetland protection coverages (Estey unpubl. data) are being created that include all lands owned by South Dakota Department of Game, Fish and Parks (SDGF&P), and all U.S. Fish and Wildlife Service (FWS) national wildlife refuges (NWR), waterfowl production areas (WPA), and perpetual easements. These wetland protection coverages will be incorporated into the final stewardship layer of SD-GAP. In general, most protected lands identified on the SD-GAP stewardship maps include national wildlife refuges, national and state parks, Nature Conservancy land, and state wildlife reserves and management areas. In eastern South Dakota, there are very few GAP Management Status Code 2 areas. For example, four FWS wildlife refuges (Sand Lake, Lake Andes, Waubay, and Pocasse National Wildlife Refuges) and all of the WPAs in eastern South Dakota comprise less than 1% of the land area (Fig. 1). Land protection in this region occurs mainly through the purchase of FWS easements.
Figure 1. Fee title lands owned by FWS in eastern South Dakota, Sept. 1994 (GAP Management Status Code 2). Use of FWS easements in a stewardship data layer represents a unique aspect of protection that has developed because of the nature of the prairie pothole landscape. The prairie pothole region covers portions of Saskatchewan, Alberta, Manitoba North Dakota, South Dakota, Nebraska, Minnesota, and Montana. In South Dakota, the prairie pothole region encompasses virtually the entire eastern half of the state. Agriculture is the major land use in this region, and approximately 35% of the prairie potholes in South Dakota have been converted to cropland (Dahl 1990). Protection of remaining wetlands is critical. However, due to the unique geographic pattern of these wetlands (most are relatively small in size and widely scattered across the landscape), fee-title acquisition of large expanses of land for their protection is more difficult than protection by easements. The majority of easements in eastern South Dakota are either wetland or grassland types. A wetland easement is an agreement between the FWS and a landowner in which the landowner will not drain, burn, fill, or level certain wetlands in return for a one-time payment from the FWS. However, the land is still vulnerable to extractive uses. For example, the land owner can plow the land and plant crops in a given year if the wetland becomes dry. If a grassland easement is purchased, the landowner agrees not to break the soil, however, the land can be grazed or mowed. In South Dakota, all wetland and grassland easements are perpetual. The Cooperative Fish and Wildlife Research Unit is in the process of producing a digital map containing all wetland and grassland easements purchased by the FWS in eastern South Dakota (Fig. 2). Township maps (approximately 1:21,000) containing wetland and grassland easements, WPAs, and NWRs were obtained from the FWS. Boundaries of these protected lands were transferred to 1:24,000 National Wetland Inventory (NWI) maps and digitized. The protection coverage will be overlaid on a modified wetland basin GIS (Naugle and Johnson, unpubl. data) derived from NWI data. In the coverage, basins were classified as temporary, seasonal, semi-permanent, or permanent.
Figure 2. Lands containing wetlands protected by FWS easements in eastern South Dakota, Sept. 1994 (GAP Management Status Codes 2 & 3). South Dakota GAP, in cooperation with the Cooperative Fish and Wildlife Research Unit, will use this coverage to aid in the construction of a land stewardship layer. All easements will be assigned a GAP Management Status Code of 3: "Legal mandates prevent the permanent conversion of natural habitat types to anthropogenic habitat types, but area is subject to extractive uses. This includes most nondesignated public lands." (Gap Analysis Program Handbook). Within the prairie pothole region, the addition of wetland and grassland easements could significantly improve to the stewardship data layers of other GAP state projects. Literature Cited Dahl, T. E. 1990. Wetland losses in the United States, 1970s to 1980s. U.S. Fish and Wildlife Service. Johnson, R. R. and K. F. Higgins. 1997. Wetland resources of eastern South Dakota. South Dakota State University, Brookings. 102 pp. |
