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What’s Hot: Some Recent Applications of GAP Data

Compiled by Elisabeth Brackney
National Gap Analysis Program, Moscow, Idaho

Ultimately, GAP will be measured by the problems and needs to which it is applied. As such, applications of GAP information are the most important items for us to track. It is also critical, though, that we share the wide variety of applications that our work has been used for, so that the GAP community has a full understanding of the actual importance of the program. What follows are just a few brief examples of applications at the state level. All GAP principal investigators, coordinators, and staff are urged to keep records of how their information is being used.


An important initiative in the state is a multiagency wetland prioritization effort where land owners can submit their land for purchase by the state for wetland conservation or remediation. The program has been so successful that more acres have been offered than can be purchased. The problem in this situation is which parcels to buy? A number of state agencies are using GIS methods to create basin-wide wetland prioritization maps that are used to prioritize conservation and remediation locations. A key data element in the effort is the GAP statewide vegetation map. Within the Mississippi and Arkansas River Valleys, bottom land hardwoods are a critical habitat type and these are identified using the GAP maps. Other data included in the modeling effort are soils, inundation, ownership, etc. A sophisticated modeling effort is also applied that includes factors such as habitat connectivity patch size and other factors.

As a result of the clear value shown by the GAP vegetation maps, the Arkansas State Legislature appropriated some $200,000 to develop a detailed land cover/land use map focusing on agriculture in the 27 counties of the Mississippi Delta in the state. Four season TM imagery is being used to identify complex crop rotation patterns and to obtain a highly accurate map. The agricultural maps will be used in addressing critical problems of water use and water quality in the region. The forest cover for the final product will be merged from the GAP vegetation maps.

GAP data are key elements in a number of other research and conservation projects in Arkansas, including fire hazard modeling, regional watershed analysis, and water resources planning.


CA-GAP staff, in collaboration with researchers from the Department of Geography at the University of California-Santa Barbara and the National Center for Ecological Analysis and Synthesis, are working on techniques for using GAP data to identify efficient networks of biodiversity management areas. These techniques, adapted from the field of operations research, address the conservation principles of efficiency, representation, irreplaceability, flexibility, and suitability. The first task was to reformulate the iterative, rule-based procedures developed in Australia into a maximal covering location problem (Church et al. 1996), which maximizes the number of species represented in a fixed number of sites. A version of this optimization modeling approach has since been integrated completely into the ARC/INFO environment (Gerrard et al. in review).

CA-GAP also outlined a protocol for the U. S. Forest Service that includes a variation of this model using GAP data to select candidate sites for new Research Natural Areas (Moritz et al. 1997; Stoms et al. in review). They developed a land allocation model that balances the efficiency of the network with the suitability of the selected sites while filling the gaps to some prescribed percentage target level (Davis et al. 1996). CA-GAP is currently working with The Nature Conservancy to adapt this model to help them identify their regional conservation portfolio. The prototype is being applied in the Columbia Plateau ecoregion and was presented at this year’s Ecological Society of America meeting in Albuquerque. An overview of CA-GAP’s reserve selection research was presented at the Society for Conservation Biology meeting in Victoria, B.C.

Editor’s note: For literature cited, see California status report.


The USGS-BRD Across Trophic Level System Simulation (ATLSS) is developing a set of models to integrate lower trophic levels, fish and macroinvertebrates, and large consumers across the freshwater landscape of the Everglades and Big Cypress Swamp. A major objective of these models is to compare the future effects of alternative hydrological scenarios on the biotic components of the systems. The Florida GAP land cover classification is providing the base vegetation map for ATLSS modeling.

Additionally, a high-resolution hydrology GIS layer was needed to adequately simulate plant and animal dynamics in ATLSS. The High Resolution Hydrology (HRH) model uses the Florida GAP land cover map as one of its primary inputs. The HRH model creates a pseudotopography GIS layer with an undulating surface that corresponds to the topography underlying the vegetation as classified by the Florida GAP land cover. The model calculates the volume of water in each grid cell, redistributes it over the high-resolution topographic surface by "balancing" the surface and subsurface volumes, and calculates the water surface elevation. The output of the HRH model is used as a primary input to the ATLSS plant and animal models.


ME-GAP personnel cooperated with the Maine State Planning Office to complete "A Conservation and Public Lands Database" (CAPLD) for the state. The 1:100,000 scale CAPLD includes many revisions and updates to previously released 1:250,000 scale land ownership maps and was constructed to meet GAP specifications. The final coverage contains about 3,130 polygons for 120 owners and includes state and federal lands, tribal lands, private nonprofit conservation lands (e.g., those owned by The Nature Conservancy), and selected public areas not managed for biodiversity (e.g., playgrounds, cemeteries, campuses). Each ownership block is coded as to consideration given to biological diversity in management plans. CAPLD has been provided to cooperators in digital and paper form and has been passed on to the state GIS office for distribution to the public.

Massachusetts, Connecticut, Rhode Island

At the regional level, Southern New England Gap Analysis data sets are being used in the planning efforts for the Silvio Conte National Fish and Wildlife Refuge, a new, multistate, watershed-based effort in New England. Gap Analysis data sets are also being used in workshops to train land use planners in biodiversity conservation in the Connecticut River Valley of western Massachusetts.

The Massachusetts Gap Analysis team also continues to be involved with international initiatives in biodiversity inventory, cooperating with projects in Romania, Madagascar, Mexico, Guatemala, Brazil, and Peru. Curt Griffin is currently on sabbatical in South Africa, working on prioritizing biodiversity conservation efforts in KwaZulu/Natal Province. Vegetation mapping and conservation planning are also being carried out in the Danube Delta, Ukraine, and Botswana.

In cooperation with Conservation International, most of the national parks in Madagascar have been inventoried using high-altitude 35-mm digital cameras in combination with low-altitude georeferenced videography. Similar efforts are being conducted in a number of biosphere reserves and national parks in Central and South America. The goal of these projects is to develop base vegetation maps to provide a tool for monitoring and change detection. The focus is on rapid development of in-country GIS capabilities, making critical data available for resource management decisions, and institutional strengthening within these host countries. The Gap Analysis approach is rapidly being integrated in conservation management programs around the world.


The Geographic Resources Center (GRC) at University of Missouri is compiling a risk database to be used in conjunction with GAP data to conduct analyses at the state level. Risk surfaces are being created for the state, addressing population, social, economic, and land use change information that will be used by decision makers as an aid in evaluating the status of Missouri’s biological diversity in the context of development and policy change.


A mosaic poster has been created from the GAP TM data and has been widely used within Nebraska to foster collaboration and improve public relations. This image of the state has helped the public understand remote sensing technology and captured imaginations on what can be achieved.

New Mexico

Some applications of NM-GAP information are: biotic mapping comparisons in northern NM mountain ranges; information coverages for county open space evaluation; and incorporation as criteria in land parcel evaluation by NM Department of Game and Fish for conservation planning and acquisition.

New York

GAP information in New York has led to more detailed mapping of land cover of the Hudson Valley corridor, between Albany and New York City. A higher resolution analysis of this region will facilitate conservation planning and decision making for this fast-growing region of New York.

North Carolina

The NC-GAP information is the basis for a "mini-Gap Analysis" project titled "A Model Biodiversity Analysis for Southeastern North Carolina" being carried out by the North Carolina Heritage Program and the North Carolina State Museum of Natural Sciences.

Vermont/New Hampshire

The Gap Analysis Project in Vermont and New Hampshire has become fundamental to biodiversity management in these two states. New Hampshire has established a committee for ecological reserve design, and much of their GAP data and mapping expertise is being incorporated into that project. The Vermont Biodiversity Project is a similar project that has the objective of mapping potential conservation areas that will assure the protection of biological diversity. Coordinated by the Vermont Chapter of The Nature Conservancy, this effort includes a long list of state, federal, private, and university cooperators.


In a cooperative effort between WA-GAP and the U.S. Fish and Wildlife Service, the role of National Wildlife Refuges (NWRs) in conserving biodiversity in Washington State was examined. The resulting report shows that NWRs often protect habitats and species that are poorly represented on other conservation reserve lands. NWRs provide some habitat for 92% of the native vertebrates breeding in the state; for 16% of native vertebrates, NWRs are the main source of protection. The report presents management recommendations and priorities for individual refuges, based on WA-GAP’s landscape-scale assessment, and indicates research needed for management of specific habitats and species.

Cassidy, K.M., M.R. Smith, C.E. Grue, and R.E. Johnson. 1997. The role of Washington State’s National Wildlife Refuges in conserving the state’s biodiversity. Washington Cooperative Fish and Wildlife Research Unit, University of Washington, Seattle, 86 pp.


The University of Wyoming’s Spatial Data and Visualization Center (SDVC) and the Biological Resources Division (BRD) of the U.S. Geologic Survey have created a partnership to implement a county-level planning support project. This project will assist Teton County, Wyoming, in creating a biological decision support system in a desktop computing environment to help promote biological considerations in traditional land use planning and management decision-making processes. The system will incorporate the completed Wyoming Gap Analysis databases and other natural resource databases with a simple graphical user interface and custom-designed tools that will not require prior knowledge of GIS or biology on the part of the planning staff.

The support system will be a tool that Teton County’s planners may use to 1) assess their current land use plans and zoning in relation to biological resources, and 2) identify potential conflicts between biologically significant habitats and proposed development.

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