The Great British summer is finally on the way… according to ZSL London Zoo's penguins.
Keepers have noticed that the 50-strong colony at the Zoo's Penguin Beach exhibit have started piling on the pounds ready for their annual moult; which takes place every summer.
Each penguin is weighed weekly – hopping on the scales before diving into their pool for a morning swim - so that their keepers can monitor their health and predict when the penguins will begin their moult.
Penguins' feathers go through quite a bit of wear and tear – they rub against each other, scramble over rocks and spend lots of time in the water, so every year they lose all of their feathers and grow a completely new set.
Head of Birds at ZSL London Zoo, Adrian Walls said: "While most people put themselves on a strict diet in preparation for a summer on the beach, penguins are the exact opposite and do everything they can to fatten themselves up.
"We trained the penguins to jump on the scales for us, so that we can estimate when the moult will begin, and we've noticed that Ricky the Rockhopper and co. are all looking more rotund – a sure sign that summer is on the way."
The old feathers stay in place until the new feathers start coming through, so the usually-pristine penguins can look quite scruffy during the moulting process.
Adrian added: "Some of our penguins are really vain characters and hide behind their flippers when they're looking a bit bald."
The penguins spend more time on land while they lose their waterproof layer, but as they all moult at slightly different stages, visitors to ZSL London Zoo are guaranteed to see those with their brand new feathers showing off in the two-metre deep pool during the daily Penguin Beach Live! talks.
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