Mr Weeks, who remained with his namesake through the night, said seals tend not to eat during moulting and conserve their energy.

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But recent research has shown that some wild birds' patterns of flights and stopovers during migrations, or moulting times, differ between El Nino and La Nina years.

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Lisa Argilla, a vet at Wellington Zoo, said the penguin had possibly struggled to find enough food or had had problems hunting and had come ashore as he needed to go through his seasonal moulting.

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