Generating Maps and Grids

The geocoded data of Ugandan village boundaries was obtained through the Ugandan National Planning Authority, by compiling a shapefile using census and election commission records, accessible at [https://scholarsphere.psu.edu/concern/generic_works/k0p096889c]. The Uganda shapefile was entered in ArcGIS version 10.4.1 for desktops (Environmental Systems Research Institute (ESRI), USA, http://support.esri.com/Products/Desktop/ArcGIS-desktop/arcmap/10-4-1) and converted to points using the ArcGIS ‘feature to point’ tool. Then, the centroid of each village was used to generate the XY coordinates with the ‘geometry’ tool.

The ‘fishnet’ tool in the data management toolbox of ArcGIS was used to create the grid at 0.1° × 0.1° (Fig. 1A). The centroid of each grid square was used to generate the XY coordinates with a ‘calculate geometry’ tool. Grid point (1, 1) was the latitude 1.9°S, longitude 29.5°E. The grids increment by 0.1° until the extent of Uganda is enclosed (1.9°S–4.2°N and 29.5°E to 35°E).

Bwindi impenetrable forest (Fig. 4A) was selected from the Ugandan map using the ‘select by attribute’ tool in ArcGIS. The selected features were then saved as a shapefile using the ArcGIS ‘create a layer from selected feature’ tool.