A North Otago sanctuary has taken "extreme" action to save the lives of this season's yellow-eyed penguin chicks.
Penguin Rescue monitors two colonies of the endangered birds on the Moeraki Peninsula, south of Oamaru, and this summer most of their enclosures are full of healthy patients.
It is the first time in thirty years volunteers have taken nearly all healthy chicks from their nests and into protected care.
The decision was made by staff to do this after the discovery of dead birds, who were most likely killed by ferrets.
Penguin Rescue sanctuary manager Rosalie Goldsworthy said because the birds are wild, intervening in their population is an "extreme" event.
This season, just one of the coast's 49 chicks has been left in its nest with its parents on guard.
The yellow-eyed penguin - or hoiho - is the world's rarest penguin. There are fewer than 160 nests in mainland New Zealand, and there are two males for every female.
"We are talking about extinction in the short term. We're talking about extinction within 10 years," Goldsworthy said.
The birds being cared for at Penguin Rescue represent about half of all chicks left in New Zealand.
The sanctuary relies on volunteers and private donations to operate, but it wants the Government to do more for the conservation of yellow-eyed penguins.
The chicks will stay at the sanctuary until they fledge in February, and will go straight to independent living in the ocean.