A pair of stoats are eluding trappers on Motutapu Island, which is meant to be a pest-free sanctuary.

The island's had four stoat invasions in one year, after first being detected on Motutapu and Rangitoto islands in May 2020.

Two stoats have been caught.

The Department of Conservation and Ngāi Tai ki Tāmaki are working hard to trap two remaining stoats

A 30-day rāhui is being be placed on Motutapu, with access to Motutapu restricted and campsite bookings unavailable during the period.

DOC Incursion Response Advisor Claire Warren told Heather du Plessis-Allan stoats can move between islands via water.

"The only way they can get there is by swimming, very strong swimmers in fact. In calm, favourable weather they can swim three kilometres or more."

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