Struggling penguins felled by parasite

Something is killing this spring's crop of yellow-eyed penguins.

It's not the stoats, cats and hedgehogs that plague the nests and chicks of seabirds elsewhere.

In March, Big Fluffy, a three-month-old chick just days from independence, was found dead on the Anglem coast of Stewart Island.

His loss was the full stop to a season-long death sentence that claimed every last one of the colony's penguin chicks.

Big Fluffy was named because he was fully feathered, had put on good body weight and plenty of fat reserves.

He should have made it.

But a postmortem at Massey University found leucocytozoon - a blood parasite carried by sand flies - in his liver, producing symptoms similar to malaria.

Leucocytozoon first turned up in penguin chicks in 2004, the final blow in a one-two combination led by another disease, diphtheritic stomatitis.

Also known as avian diphtheria, it struck yellow-eyed penguins from Oamaru to Stewart Island, sapping their breeding effort in 2005 to a record low.