On the trail of the rare yellow-eyed penguin
Crawling through bush tracking feather trails is an important part of conservation work for the yellow-eyed penguin.
Massey University conservation biology master’s student James Roberts spent three weeks in March in the South Island working with the Yellow-eyed Penguin Trust during the moulting period of the rare penguin, or hoiho.
Roberts and staff from the trust and the Department of Conservation would crawl through thick bush or negotiate slippery banks looking for the distinct feather trails. They would catch penguins, weigh them and do a health check.
His involvement came through the Blake Ambassador Programme, which aimed to get young people involved in science and conservation projects.
The hoiho was one of the rarest penguin breeds and numbers have been in decline. There were only about 160 breeding pairs on the New Zealand mainland.
But Roberts said because of the trust’s work, there had been an increase in chicks surviving.
He spent two weeks working on the Dunedin coastline, then a third in the Catlins at the southeast corner of the South Island, making sure underweight birds were fed during the moult.
Moult season is from February to April, when the penguins shed and replace their waterproof feathers. During the few weeks they are moulting, they don’t go into the ocean to eat, so lose weight.
Roberts said some penguins were starting moulting underweight because they couldn’t get enough food as fish stocks were depleted.
“When they finish their moult, they don’t have enough energy to get out and fish, so they end up starving. It’s a brutal cycle.”
The birds should start at about 7.5kg, but if they were underweight the trust would intervene.
“They’re facing a lot of threats, as are a lot of other marine species, and one of the large threats is starvation.”
If a penguin was underweight, they were fed until they were back to normal weight, then released.
Roberts said one of the biggest threats to the birds was human curiosity, because if a penguin was in the water and a person was standing nearby, it wouldn’t come ashore to feed its chicks.
He had many bruises and scratches from the birds biting or giving karate chops with their flippers.
Yellow-eyed Penguin Trust science adviser Trudi Webster said if the birds were underweight it was possibly because they weren’t getting enough food, which could be caused by multiple things such as regular food sources not being available.
“We are intervening with a lot of the birds. We’re talking quite low numbers of birds overall because there's been a 78% decline in the last 15 years.
“There are now 160 breeding pairs in the northern population in mainland New Zealand and then this year we probably would have taken 50% of the breeding birds into feeding.”
She said the 78% decline was a terrifying statistic.