Scientists are baffled by the deaths of thousands of penguins in the Falkland Islands.
A Falklands farmer, David Pole Evans, was the first to notice that something was amiss when he saw penguins "just standing around, not looking very fit or healthy" in April.
A few weeks later, he found thousands of dead penguins on the shore of Saunders Island and in the surrounding waters.
He told the BBC that he estimated as many as 9,000 rockhopper penguins and 1,000 gentoo penguins, which are native to the South Atlantic region, have died so far.
Post-mortem examinations have failed to produce any firm conclusions. Nick Huin, the scientific officer from Falklands Conservation, a charity, said: "We're worried, because we don't know exactly why it's happening."
Tracking devices have been attached to 10 penguins in an attempt to solve the mystery. But Mike Bingham, a researcher who works with the International Penguin Conservation Work Group, based on the islands, said there was "no doubt" that the penguins are dying from starvation.
The local penguins have been moulting a month later than usual. When they moult, they are no longer waterproof and therefore come ashore. But once removed from their food source, they need to be fat enough to survive on land.
One possible explanation for the deaths is overfishing. Another is a drop in the sea temperature caused by the melting of Antarctic glaciers as a result of global warming. The cooler waters have caused the penguins' food source of squid to remain in Argentinian waters rather than move on the current to the Falklands.
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