A stoat caught in a trap on a predator-free island in the Marlborough Sounds likely swam across from a nearby island, according to DOC.
The predator was captured on a Oruawairua/Blumine Island trail camera in July, and DOC became aware of it in mid-August during a monthly photo review.

Stoats were the number-one killer of many of NZ’s endangered species. Oruawairua was home to vulnerable bird species such as the kÄkÄriki karaka, mohua and tÄ«eke/saddleback.
DOC Picton biodiversity ranger Amy Brunsden said quickly trapping the stoat was the best result possible, and showed the value of the trapping and surveillance network on the island.
āCritically endangered kÄkÄriki karaka nest and roost in tree holes so theyāre extremely vulnerable to predation and even one stoat could do lots of damage,” she said.
āTo be sure it was only one stoat, weāve also put out extra trail cameras and tracking tunnels which detect introduced predators. A trained stoat detection dog will also check the island.ā
Stoats were surprisingly good swimmers, she said. While this one likely swam around 400m across from nearby Arapaoa Island, they have been recorded swimming as far as 5km.

She said it was a good reminder for people to not take public eco-sanctuaries like Oruawairua for granted, and to follow quarantine procedures.
“Everyone has a role in protecting nature.”