Humans join hunt for Antarctica's "pink gold"

By Alister Doyle, Environment Correspondent

TROLL STATION, Antarctica (Reuters) - They only grow up to 2.4 inches yet are perhaps the most abundant creatures on the planet in terms of weight. Snow petrels nesting in Antarctica fly for up to eight hours to catch a meal of them.

Krill -- small shrimp-like crustaceans which with modern technology can be used in fish feed, human dietary supplements, soya sauce flavoring, pharmaceuticals, or even to clean the paintings of Old Masters -- are in increasing demand.

A "pink gold" which if fed to farmed salmon cut out the need for colorants to make the flesh pink, krill are extremely rich in Omega-3 fatty acids, linked to health benefits for people.

Occurring in all oceans but most abundant in the Southern Ocean, they are also the staple diet for seals, penguins and whales as well as for the snow petrels living on icy mountains inland, which fly more than 500 km (300 miles) for each meal.

But rising human demand for fish oils, likely to bring more competition from trawlers for krill, is causing concern that this keystone species near the bottom of the food chain should not be overfished.

"The krill catch is projected to go up with other countries getting involved," said Stephen Nicol, a krill expert at the Australian Antarctic Division, adding that current catches seem no threat to vast stocks.

"But there's a lot of concern because this is a keystone species -- whales, penguins and seals depend on it," he told Reuters by telephone. "But part of that dependence is because there's a lot of krill."

Led by Norway, annual krill catches total 120,000 tonnes, a tiny share of a Southern Ocean stock estimated at anywhere from 100 to 500 million tonnes. Japanese, South Korean and Polish vessels also have krill licenses under an international deal.