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Gap Analysis Bulletin No. 10

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Taking Refuge-GAP a Step Further: The GAP Ecosystem Data Explorer Tool in the Roanoke-Tar-Neuse-Cape Fear Ecosystem

Steven G. Williams¹, Casson Stallings², JohnAnn Shearer³, and Alexa J. McKerrow¹

¹NC Gap Analysis Project, NCSU, Raleigh, North Carolina
² ManTech Environmental Technology, Inc., Research Triangle Park, North Carolina
³USFWS Ecological Services, Raleigh, North Carolina

More and more land management agencies and conservation organizations are focusing their efforts on ecosystem conservation.  In doing so, they have turned to Geographic Information Systems (GIS) to provide the analytical tools to look at landscape issues.  The biological data developed by the Gap Analysis Program (GAP) is an ideal data set for these efforts.  It was designed as such.  However, the steep learning curve of GIS software and the cumbersome nature of spatial data have severely limited utilization of GAP data, and GIS in general, by the vast majority of people involved with land management.  If GAP is to realize its full potential, it must make its data readily available and applicable for use by biologists and land managers not trained in GIS, because that is where the largest impact can be made.  In an effort to address that need, the University of Wyoming's Spatial Data and Visualization Center and the National GAP Program developed an ArcView-based decision support tool designed specifically for U.S. Fish and Wildlife Refuge (FWS) managers, called Refuge-GAP (Herdendorf and Crist 1998).  While scripting for the tool was not fully developed and was built around Wyoming data, the concept proved attractive to another group of FWS personnel halfway across the continent.  Following a presentation of the North Carolina Gap Analysis Project (NC-GAP), biologists from the Roanoke-Tar-Neuse-Cape Fear (RTNCF) Ecosystem Team quickly seized on the idea of implementing GAP data through the use of a decision support tool based on Refuge-GAP.  They saw such a tool as not just beneficial to refuge personnel but also to other FWS offices, including Ecological Services and Realty as well as their Ecosystem Planning Office.  As a result, the FWS and GAP provided funding to NC-GAP for further development of Refuge-GAP into the RTNCF GAP Ecosystem Data Explorer (GEDE) Tool.

Much like Refuge-GAP, the GEDE Tool is a customized ArcView (ver. 3.2) project that displays and manipulates GAP data through a series of dialog boxes and avenue scripts.
The GEDE Tool allows users not savvy in GIS to quickly view data and conduct advanced queries with a few simple clicks.  While the GEDE Tool has been designed to be accessible to a broad audience, it is based on a full implementation of ArcView with Spatial Analyst and, thereby, provides an advanced GIS platform for those who wish to expand the complexity of their queries and analyses.

The GEDE Tool begins each session at a common starting point (Figure 1 - see Web version of Bulletin at http://www.gap.uidaho.edu/Bulletins/10).
The user can then select an area of interest (AOI) by either importing a coverage or by creating one.  Several methods of creating an AOI are presented, including selecting features from standard coverages (e.g., quadrangles, counties, watersheds, refuges, etc.) or by direct on-screen digitizing (Figure 2).  Once a user has defined an AOI, the Tool queries the known general ranges, tessellated by the EPA hexagonal grid, of all species to show only those species having a possibility of occurrence within the AOI.  The user is then presented with a series of choices designed to narrow the list of species.  For example, the user can choose to continue with only federally or state-listed species, high-scoring Partners-In-Flight species, priority species as defined by The Nature Conservancy, species with a user-defined minimum percentage of their predicted distribution on highly protected lands, or any combination thereof.  Following that choice, the user is presented with a dialog box listing the selected species present, which allows the user to display either their predicted distribution, known range, or confirmed locations with a single click (Figure 3)>.
The user can also display the ownership, management, or protection status of a species' predicted distribution or view a species report, which contains information on taxonomy, habitat preferences, distribution modeling, literature citations as well as a quantitative summary of the areal extent of the predicted distribution by management agency throughout the ecosystem.  The user can also choose to calculate a similar summary within just the selected AOI as well as select multiple species to create customized diversity maps.

Figure 2. Select Area of Interest Dialog Box.  Two methods to select an Area of Interest are presented, including selecting features from coverages and on-screen digitization.

Also built into the GEDE Tool is a spatial representation of the Land Acquisition and Prioritization System (LAPS) employed by the FWS to prioritize lands for acquisition (http://realty.fws.gov/laps.htm).
LAPS is designed to be an impartial score of conservation value based on four components: Aquatic and Wetland Resources, Landscape Conservation, Bird Conservation, and Endangered and Threatened Species.  While not all scoring criteria used in LAPS are readily transferred to a spatial framework, we identified and created eleven spatial data layers representing various components and subcomponents that can be used as a spatial surrogate for LAPS (Table 1).  Once a user selects a Project Area and Landscape Effort polygon a twelfth layer is created based on areal extent and is summed to the other eleven data layers to create the final LAPS data layer, which is then displayed in the main view along with a dialog box that allows the user to select any of the four component or 10 subcomponent data layers for display as well (Figure 4).

Table 1.  LAPS spatial data layers