Displaying changes in bird distributions between SABAP1 and SABAP2

Abstract

One of the objectives of the Second Southern African Bird Atlas Project (SABAP2) was to be able to make comparisons with the distribution data collected during the First Southern African Bird Atlas Project (SABAP1); the spatial grid for SABAP2 was set up with a view to facilitating this. Strategies to make these comparisons have proved to be more difficult than were anticipated at the outset of SABAP2 in 2007. The objective of this paper is to document a procedure to construct maps which show the changes in bird distribution patterns between the two projects.