Patterns of Species Richness in the High Seas

W. Cheung, J. Alder, V. Karpouzi, R. Watson, V. Lam, C. Day, K. Kaschner, D. Pauly, (2005). “Patterns of Species Richness in the High Seas,” Secretariat of the Convention on Biological Diversity, Montreal, Technical Series No. 20 (Secretariat of the Convention on Biological Diversity, Montreal, Canada

Maps of the species richness in the high seas are presented, which are based on the distribution of individual species of marine invertebrate and vertebrate groups, complemented with maps of genera and families of invertebrates and fishes. High seas refers to marine areas outside the 200-mile exclusive economic zones (EEZs) and continental shelf areas, or other described national jurisdictions.We considered known latitudinal and longitudinal gradients of the distribution of species richness (declining from the equator, and from a global center of species richness about Indonesia) where appropriate. Maps of the known locations of cold-water corals and seamounts are also presented. There is suggestive evidence that cold-water coral are associated with seamounts. If validated, this would allow predicting the existence of far more cold-water corals sites than so far documented. Both habitat types are threatened by trawling. Lastly, a map of the distribution of threatened non-fish vertebrates is provided. Together, these maps indicate marine biodiversity in the high seas to be richly patterned, with some of these patterns helping to identify areas in need of protection such as seamounts, and the high seas of the Southwest Pacific.