- How many species are there in the oceans?

by Prof Nic Bax, Director, CERF Marine Biodiversity Hub

The Census of Marine Life, National and Regional Implementation Committees were set the task of estimating the number of marine organisms in their waters. The results of these studies and a synthesis study are the foundation of the new Public Library of Science (PLoS) Hub for Biodiversity. The Australian synthesis, led by Alan Butler who leads the Biodiversity Program, involved Hub scientists from CSIRO and Museum Victoria with additional assistance from the Australian Biological Resources Study (ABRS). No single database exists that summarises Australia’s marine flora and fauna – the researchers amalgamated data from 4 major databases, supplemented with additional records from a mixture of specialist databases and expert knowledge. They concluded that there are about 33,000 marine species (mainly animals) in the major databases, of which 130 are introduced, 58 listed as threatened and an unknown percentage endemic. An estimated 17,000 more named species are either known from the Australian EEZ but not in the present databases, or potentially occur there. It is crudely estimated that there may be as many as 250,000 species (known and yet to be discovered) in the Australian EEZ. This estimate does not include the hugely diverse microbial world. Sadly the authors also note that taxonomic expertise in Australia is unevenly distributed across taxa, and declining.

http://www.coml.org/census2010