Oceanographers involved in a decade-long Census of Marine Life in the oceans of the world have catalogued an unprecedented number of small, ocean-dwelling microbes – the vast numbers of the organisms having evidently taken them by surprise!

The researchers, during the course of their nearly 300 voyages, are astonished at the extent of new discoveries of microbes – which comprise 90 percent of all marine biomass; and have begun to re-assess their estimates pertaining to the existing knowledge about marine life.

Noting that zooplankton, microbes and sediment-dwellers have been sampled during the census, lead researcher Dr Ann Bucklin, head of the University of Connecticut Marine Sciences Department, said: “There are many more species than we thought there were. It turns out the ocean food web is much more complex than we thought it was, in terms of the number of different species.”

For the census, the research team used DNA-sampling methods for cataloguing the “new world of marine microbial diversity and abundance,” as Mitch Sogin, head of the International Census of Marine Microbes put it.

The researchers dragged big nets, reaching up within 1-5 kilometres beneath the surface of the deep seas – finding new species and genre with every serach. While they kept some samples for taxonomic study; others were investigated for their DNA.