Hoiho rescue mission a success

A joint mission to save Moeraki’s yellow-eyed penguin (hoiho) chicks from a deadly virus has been a stunning success.

Late last year, about 70 hoiho chicks were rushed to the Dunedin Wildlife Hospital when the Kātiki Point reserve penguin colony’s newborn population was hit by a potentially deadly respiratory disease.

The rescue mission mounted by Penguin Rescue New Zealand, the Department of Conservation (Doc), and the Dunedin Wildlife Hospital has saved most of the chicks.

Penguin Rescue manager Rosalie Goldsworthy said the operation was a great success compared with the previous season when half the chicks died.

"We’re so pleased ... it’s fantastic," Ms Goldsworthy said.

Dozens of hoiho chicks born in late-2022 contracted a novel gyrovirus and then succumbed to the resulting respiratory disease.

So this season, at the first signs of the virus’ return, the colony’s entire population of 3-day-old chicks was quickly taken to Dunedin.

At the wildlife hospital they were fed five times a day for up to a week.

Ten of the chicks died — five did not survive the first 24 hours.

There were also two unexpected deaths in older birds.

The chicks had to weigh more than 300g before they could return to the nesting area around the Moeraki lighthouse.

Ms Goldsworthy said the transfer and the detailed hospital care of the penguins made all the difference.

Sixty chicks not only survived but were now flourishing at Kātiki Point, she said.

"There has been a 30% increase [in the survival rate] from last year as a direct result of taking them to the wildlife hospital."

The chicks now weighed up to 5kg; an indication good nutrients at sea were being converted to healthy weight gains.

"We’re optimistic that 60 chicks will fledge in about a month."

Scientists were unsure how the hoiho chicks were catching the virus. But they did know removing the birds from their nests seemed to give them a better chance of surviving.

Ms Goldsworthy said 53 chicks were back in the nests with their parents and making good progress. Seven chicks were being closely monitored in a separate location.

"We feel like we have stopped the freefall, that we have turned the corner now and we are going to be able to make a really positive impact," Ms Goldsworthy said.

Now the penguins are stable, avian malaria is the next danger they face.

Penguin Rescue staff are taking blood tests this week to test for the mosquito-borne disease.

Any penguins with malaria would be put in a mosquito-excluded area and screened so the disease could not spread.

Ms Goldsworthy has been manager of the charitable trust since 2002.

"This is the reality that we are facing to save our birds," she said.

"The more you know about penguins the more respect you have for them because they are amazing."