The royal penguin receiving treatment at Wellington Zoo remains in a critical state, despite gaining a little weight.
Zoo spokeswoman Kate Baker said the unnamed penguin put on 100 grams yesterday, raising his weight to 2.8kg.
A healthy year-old royal penguin should weigh about 4.5kg.
"He's still alive ... [but] he's still very much in a critical condition. We are taking it day by day," Ms Baker said.
The bird was found at Tora on the Wairarapa coast on Sunday, about 2000 kilometres from its home on subantarctic Macquarie Island.
- The Dominion Post
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