“The March of the Penguins” made Warner Brothers millions, but maybe the film giant should do a sequel called “The Marathon of the Penguins”.

Latest scientific research shows that penguins from the largest colony in mainland South America are being forced to swim the equivalent of two marathons farther to find food because of climate change.

The survival of the Magellanic penguin colony at Punta Tombo, on the Atlantic coast of Argentina, is being threatened by the increasing distances the birds must travel to feed themselves and their chicks.

Dee Boersma, of the University of Washington in Seattle, said that Punta Tombo penguins were now routinely swimming 25 miles farther on their foraging expeditions than they did a decade ago.

“That distance might not sound like much, but they also have to swim another 25 miles back, and they are swimming that extra 50 miles while their mates are back at the breeding grounds, sitting on a nest and starving,” she said.

The longer foraging trips have contributed to the colony’s decline: penguin numbers have fallen by more than 20 per cent in the past 22 years, leaving only 200,000 breeding pairs today.

Penguins are not the only ones struggling.  The world’s fish stocks will soon suffer major upheaval due to climate change, scientists are also warning.

Changing ocean temperatures and currents will force thousands of species to migrate polewards, including cod, herring, plaice and prawns. By 2050, US fishermen may see a 50% reduction in Atlantic cod populations. Cod numbers in the North Sea could also fall 20 % by then too.

The predictions of “huge changes”, published in the journal Fish and Fisheries, were presented at the AAAS annual meeting in Chicago. “The impact of climate change on marine biodiversity and fisheries is going to be huge,” said lead author Dr William Cheung, of the University of East Anglia in the UK.