Marine life census estimates over 230,000 species across oceans

In what is undoubtedly the biggest and most comprehensive attempt undertaken to answer the age-old question about the number fishes in the sea, the Census of Marine Life (COML) has estimated that there are more than 230,000 species out there in the oceans.

The results of the 10-year study of the diversity, distribution and abundance of life in the world's oceans were published on 2 August.

According to Patricia Miloslavich of Universidad Simon Bolivar, Venezuela, the co-senior scientist of the COML, the survey covered species "from coast to the open ocean, from the shallows to the deep, from little things like microbes to large things such as fish and whales."

More than 360 scientists have, over the past decade, surveyed 25 regions and the results show that around a fifth of the world's marine species are crustaceans such as crabs, lobsters, krill and barnacles. Along with molluscs (squid and octopus) and fish (including sharks) they make up about half the species in the seas.

The species that are most frequently seen in conservation campaigning whales, sea lions, turtles and sea birds make up less that 2 per cent of marine species.

The study has also highlighted areas that should be of concern for conservationists.