Explorations in the Southern Ocean (SO) have yielded a pleasant surprise to marine scientists.
A young marine scientist from the Centre for Marine Living Resources and Ecology (CMLRE), Kochi, has sighted Adelie penguins ( Pygoscelis adeliae ) nearly 500 km away from Les Kerguelen Island in the Southern Ocean, on their its migratory route.
Anoop Balan, the scientist who studied the marine mammals of the Southern Ocean, spotted juveniles and adult swimming and feeding during the expedition.
International experts have communicated that there are very few pelagic records of the birds in this region, this far north. Observations were made on board Ocean Research Vessel Sagar Nidhi, he said.
The Adelie penguin is one of the most easily identifiable penguin species with its blue-black back and white chest and belly. It is the smallest penguin found in the Southern Ocean. During winter, the birds migrate north only to return in summer months, Dr. Balan said.
The CMLRE had earlier surveyed the ice-free areas of the Indian Ocean sector of the Ocean during the austral summer of 2004. Researchers had then identified Antarctic minke whales ( Balaenoptera bonaerensis ), fin whales ( B. physalus ), sei whales ( B. borealis ) and blue whales ( B. musculus ).
The CMLRE, affiliated to the Ministry of Earth Sciences, planned the expedition to obtain “information on cetacean species diversity which will help determine the distribution, migration patterns and habitat preferences of cetaceans in the Southern Ocean.”
Adelies are a highly migratory species. After breeding, they do not return to their colonies until the next spring. They feed on krill and fish. Little is known about the non-breeding distribution of this species. Records on the migration of Adelies, commonly sighted in the Antarctic coast, into the Southern Ocean almost 5 degree North are significant, said M. Sudhakar, director CMLRE, who led the first Indian expedition to SO in 2004.
The Southern Ocean accounts for about 10 per cent of the world’s oceans and supports more than 50 per cent of the world’s marine mammal biomass, including six species of pinnipeds, eight species of baleen whales, and at least seven species of odontocete whales.
The seas around Antarctica are home to a rich and diverse group of species that have evolved some unique ways of coping with the cold and hence represent a unique polar marine ecosystem.
