Exposing the secret life of the Antarctic sea-floor

Little blue jellyfish
Little blue jellyfish (Photo: Russ Hopcroft)
Antarctic sea-floor life

17 December 2007

The diversity of Antarctic fish and sea-floor-dwelling creatures will be the focus of a major Australian-led project of the International Polar Year, on board the Aurora Australis, which sailed for the Southern Ocean yesterday.

The Collaborative East Antarctic Marine Census will reveal the processes behind the evolution and survival of marine life in the Antarctic region, providing valuable information that will allow scientists to predict how these organisms may respond to climate change.

Project Leader, Dr Graham Hosie, of the Australian Antarctic Division, said that the voyage – to a Southern Ocean sector adjacent to the French Antarctic station, Dumont D'Urville – is the first of three voyages to the region over the next two months, by Australian, French and Japanese ships.

This first voyage will focus on the diversity of fish and sea-floor-dwelling ('benthic') organisms living below 200 m depth, and the environmental conditions in which they live. The next two voyages, in the French supply ship, l'Astrolabe, and Japan's Umitaka Maru, will look at biodiversity in the open ocean, especially the plankton and mid-water fish.

"Together, the three voyages will investigate the diversity of the open ocean and sea-floor fauna, from gene to habitat level, and compare these with similar studies in other parts of the Southern Ocean," Dr Hosie said.

"This will help us understand the whole community composition and structure, which in turn will help us understand the impacts of climate change and how marine communities have adapted to the unique Antarctic environment."

Voyage Leader, Dr Martin Riddle, of the Australian Antarctic Division, said the project would use traditional sampling equipment such as beam trawls, benthic sleds and sediment grabs – very similar to those used by the early Antarctic explorers a hundred years ago – as well as state-of-the-art video imaging to survey more delicate creatures, such as sea-pens and corals, and the latest molecular genetics techniques.

"The logistics of working in the Antarctic are always complex, and a major international collaboration such as this, with participants from all over Australia and from several other countries, and involving many different sampling techniques, is the culmination of many months of planning," Dr Riddle said.

"We've now got the really exciting part ahead of us – discovering what lives down there."

The project is part of the international Census of Antarctic Marine Life, being coordinated by the Australian Antarctic Division, which will see some 16 voyages to Antarctic waters during this, the International Polar Year (2007-2009).

Over five years the Census of Antarctic Marine Life will survey the biodiversity of Antarctic slopes, abyssal plains, open water, and under disintegrating ice shelves. The census aims to determine species biodiversity, abundance and distribution and establish a baseline dataset from which future changes can be observed.