Mark Endries, US Fish & Wildlife Service, NC, with US Fish and Wildlife Service Asheville ES Office Staff.
International Conservation Mapping Competition Essay – Mark Endries, USFWS
Wildlife faces a myriad of benefits and threats to their well-being. If one considers all of the benefits and threats to wildlife as a system, this system is very complex. A challenge to those responsible for the conservation and preservation of wildlife systems is the ability to efficiently provide information on these systems to those who need it.
The U.S. Fish and Wildlife Service’s Asheville Field Office (AFO) is responsible for reviewing for endangered species compliance all federally authorized, funded, and permitted projects, and implementing listing and recovery activities for federally listed endangered and threatened species and candidate species of concern in Western North Carolina (WNC). Paramount to the ability of the AFO to effectively implement listing and recovery actions, as well as educate constituents on conservation issues in WNC, is a tool to provide conservation information in an effective manner. This tool would permit landscape-scale evaluation of a proposed project to assess its impact on lands important to fish and wildlife species. In an effort to prioritize the work area of the AFO and share this information with AFO constituents, the AFO used geographic information systems (GIS) to develop a work area habitat prioritization map. This map incorporates a wide variety of land use, land cover, and wildlife species data to rank the AFO work area landscape on a 1-10 scale based upon federal trust resource priorities of the AFO staff.
Geographic Information Systems provide an ideal tool for regional assessments of landscapes, development and application of habitat models, and modeling of the potential distribution of species and habitats. GIS have also emerged as a tool to assist in the resolution of land use conflict and the management of natural resources. Given appropriate digital habitat and wildlife data, these data can be used to identify environmentally sensitive lands, to allow GIS users to view their project in a landscape prospective, and to allow habitat quality and wildlife needs to be simulated as a function of proposed management.
One fundamental tenant of the AFO work area habitat prioritization map was that all aspects of its creation, from methodology to data presentation, must be easy to understand for scientists and non-scientists alike. This was achieved this by categorizing all map input layers into two major categories, ranking all map input layers and the final map on a 0-10 scale, and keeping the modeling methodology simplistic yet effective. As a result, users of the map and associated datasets need not be GIS experts to understand and use the information.
To begin the mapping process, all of the available spatial data relevant to wildlife in WNC were compiled and processed into GIS data layers (map input layers). The AFO utilized data from over 15 different agencies. Initially, 24 GIS map input layers were constructed and used in the mapping process. The map input layers were organized into two categories; layers beneficial to federal trust resources (beneficial layers) and layers which are a threat to federal trust resources (threat layers). All map input layers were classified on a 0 to 10 scale; with 10 being of most benefit for the beneficial layers, and 10 being of greatest threat for the threat layers. By doing this, all layers were scaled the same using an easy to understand range of values. Using the stackstats command in workstation ArcInfo GRID, A correlation analysis was run to identify significant correlation between the data layers. Significant correlations among data layers were resolved by removing 8 layers from the modeling process. Next, AFO staff ranked each map input layer on a 1 to 10 scale based upon perceived benefit or threat to federal trust resources and an average layer rank was calculated for each map input layer. To calculate the final map, all map input layers were multiplied by their AFO rank and summed by category (benefit or threat). The final step was to subtract the sum of the threat layers by the sum of the beneficial layers and classify the result into a 1 to 10 scheme. For the final map, a high score indicates an area that ranked high in the beneficial input layers (numerous benefits) but low in the threat input layers (limited threats). A low score indicates an area that ranked low in the beneficial input layers (limited benefits) but high in the threat input layers (numerous threats). The AFO generated a custom 10 class color ramp for this map to highlight the high ranking areas. Colors scale from light gray to dark gray, light green to dark green, yellow, orange and then red as the values in the final map increase from 1 to 10. For this color ramp, as the values increase the colors become “hotter”, similar to how a weather map shows intensity of storms.
The AFO feels that the poster effectively summarizes the map and informs people on AFO work area priorities even with just visual interpretation. ESRI’s ArcGlobe was used to create a perspective image of the final map. By placing small images of each model input data layer above this perspective image, it gives the appearance that these data layers are hovering over the final map. A blue arrow tree (center in the poster) was used to point from each map input data layer downward, combining into a single arrow and pointing to the final map. This blue arrow tree graphically represents the actual combining of each individual model input layer and draws the viewer’s eyes down to the final map. All of this informs the viewers without any text that the data layers were combined to create the final map. The key to this was the transparency of the bottom of the arrow tree to further give the appearance that all the layers and blue arrow tree are hovering over the final map.
The AFO work area prioritization map data is provided in a file geodatabase along with all of the input data layers free of charge. By providing the data in this format, users have the full capabilities of GIS to perform further analysis or inquiries with the data. For example, by using the identify tool in ArcGIS, users can identify individual pixel values of the work area prioritization map results and any map input data layer at specific locations. This allows users to get a clear understanding of the importance of each map input data layer at specific locations. Users can also use their own data in conjunction with the work area prioritization data. Users can customize and recalculate the work area prioritization by adding or removing data layers to better fit the specific task at hand, improving the utility of the work area prioritization map by giving it the flexibility to suit the needs of specific projects or queries.
The AFO work area prioritization map has been an effective means to share information on wildlife needs to AFO constituents. Fundamental to the project is the power of GIS to create information out of data and present it in an efficient manner. As new or better data becomes available, the AFO will update the map to keep it as current and accurate as the data available.