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Antarctica's 'pink gold'
30/01/2008 13:32 - (SA)
Troll Station - They only grow
up to six centimetres 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 flavouring, 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 500km 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 said. "But part of that dependence is because
there's a lot of krill."
Led by Norway, annual krill catches total 120 000 tons, a
tiny share of a Southern Ocean stock estimated at anywhere from
100 to 500 million tons. Japanese, South Korean and Polish
vessels also have krill licences under an international deal.
Norway says it already thinks about the ecological impact of
its krill fishing.
"We are concerned to catch krill in an environmentally
sustainable way," Norwegian Prime Minister Jens Stoltenberg told
Reuters during a visit to the Troll research station, 250km
inland where snow petrels nest under rocks.
Krill oil
Norway's Aker BioMarine, which operates the most advanced
krill trawler, aims to launch a krill oil diet supplement in 500
shops across the Nordic countries, and separately in the United
States, by the end of March 2008.
"In 2007 we caught 40 000 to 45 000 tons of krill," said Helge Midttun, chief executive of Aker BioMarine. Assuming
regulatory approval, the "Superba" oil capsule will be Aker's
first krill product for humans.
Canada's Neptune Technologies & Bioresources will be its
main competitor. On January 23, a US panel ruled that
Neptune's oil, already sold as health oil in capsules, was also
safe as an ingredient in food, paving the way for its wider
commercialisation in the United States.
Neptune signed research deals in 2007 with Swiss food group
Nestle and with the Yoplait dairy unit of US food maker
General Mills Inc over use of krill in foods.
"Krill is not over-fished ocean-wide ... we can still create
a sustainable fishery," said Jerry Leape, director of the
Antarctic Krill Conservation Project at the Pew Environment
Group in the United States.
"But much of the fishery concentrates in areas where krill
swarms are most convenient. And that is where many natural
predators also depend on krill," he said, adding that trawlers
should be forced to spread catches around the continent.
Among predators, pigeon-sized snow petrels and Antarctic
petrels are extreme examples of dependence on krill when
nesting, since there is no food on land in Antarctica for them
to eat.
"These birds fly 250 km before they find water, and further
before they find krill," said Kim Holmen, research director at
the Norwegian Polar Institute, at the base, which is surrounded
by mountains that look like the homes of mythical trolls.
"When they leave their nest it's six to eight hours before they
collect any food," he said. When nesting, male and females share
the trips, taking three to five days before arriving back with food.
"It's a survival strategy. If you live closer to the shore
you have more enemies and competition for nest sites," he said.
Catch safeguards
Krill fishing briefly peaked in the 1980s when the Soviet
Union caught up to 500 000 tons a year and canned it for human consumption. But because krill release damaging enzymes and
decay quickly, scientists say they probably tasted bad.
Net technology developed by Aker BioMarine delivers a stream
of live krill onto the vessel, overcoming the enzyme problem and
avoiding a damaging by-catch of other species.
Midttun of Aker BioMarine said the company was converting a
second vessel for krill catches, alongside its existing Saga
Sea.
The company, which co-operates with the WWF conservation
group in monitoring its krill fishing, says it might be able to
catch 200 000 tons of krill a year in a few years' time.
Midttun said the Commission for the Conservation of
Antarctic Marine Living Resources (CAMLR), which sets quotas,
reckoned catches could sustainably rise to one percent of the
total biomass of krill, or five million tons a year if the total
was 500 million tons.
He said the Commission was a good way to manage the fishery
- safeguards are being set up before big catches happen. Even
so, CAMLR says it has been unable to stop illegal catches of the
Patagonian toothfish, another Antarctic species it oversees.
But scientists say little is known about the history of fish
stocks and global warming could be a problem -- it is unclear
how far krill depend on algae that bloom near the ice shelves
around Antarctica, and climate change could melt some of the
ice.
"One of the big questions is what happens if the sea ice
disappears," Nicol said. "It's very unclear. There are krill
populations around (the island of) South Georgia where there is
no sea ice."
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