Evaluating EBSAs and PSSAs

Spatial Distribution of EBSAs
Figure 1 shows the boundaries of the EBSAs defined by the Convention on Biological Diversity. With such large overarching criteria, it is clear that their spatial extent and number are significant. EBSAs number in excess of 290 worldwide, accounting for some 2.2 x \(10^{13}\) \(km^2\)of ocean and coastal waters.

Global distribution of EBSAs

Spatial distribution of PSSAs
Figure 2 shows the spatial extent for the 13 PSSAs presently agreed by the IMO. Boundaries for three (check) further putative PSSAs have not been included, due t lack of accurate geo-referenced data. These areas are significantly less in number and extent, accounting for some 5.3.x 106 km2 of ocean and coastal waters.

Global distribution of PSSAs
Spatial distribution of the overlap between the two areas of designation 
Figures 3 and 4 highlight the major areas of overlap between EBSAs and PSSAs. The total area of overlap represents some 3% of the area bounded by present-day PSSAs, the majority of which is covered by the area surrounding the Galapagos Islands (A). Areas such as the Peruvian Upwelling Core (C), the Eastern Caribbean (D) and Malpelo Island (B) are extremely small; in truth the PSSAs just clip these EBSAs (Fig. 3). The only other significant area of intersection occurs within the Straits of Bonifacio in the Mediterranean (Fig. 4)