Auckland's Motutapu Island could be plagued by two stoats — not one

Thursday, 22 April 2021

Nine weeks after first being spotted, an elusive stoat is still on the run from the Department of Conservation on Auckland's Motutapu and Rangitoto islands (video first published July 25, 2020).

DNA evidence taken from stoat scat and swabs from killed birds suggest there may be at least two stoats running rampant on Auckland’s Motutapu Island, not one.

For about four months, the Department of Conservation (DOC) Ngāi Tai ki Tāmaki and the organisation Kiwis for kiwi have been trying to trap the elusive pest.

It has seen the island’s population of 10 tūturuatu (shore plover) evacuated to a sanctuary and wildlife centre.

It is not yet known when they will return to the island, despite DOC earlier saying it would be the end of this month.

There are at least stoats on Motutapu Island, and they continue to evade capture (File photo).

* Takahē could be latest victim of stoat on Auckland's Motutapu Island

* Hunt on to catch another stoat in Auckland's Hauraki Gulf after rare birds found dead

Nine adult and one juvenile tūturuatu (shore plover) were evacuated off Motutapu Island due to a stoat (File photo).

The birds’ evacuation came after three were found dead.

Stoat dogs will be back on Motutapu and Rangitoto islands from next week.

The tūturuatu is one of the world’s rarest shore birds. With a wild population of about 240 birds, the survival of the endangered species relies on island biosecurity, breeding in captivity and predator-free islands.

Rangers first discovered a tūturuatu dead on November 17. The others were found dead on December 16 and January 14.

They were killed at night while incubating their eggs, causing a disruption in breeding pairs and a serious setback for the Motutapu population, which has struggled to become established.

A necropsy found no evidence a takahē found dead on the island was the latest victim of a stoat.

Katherine Lane, DOC’s operations manager, said since January, they had not found any more birds killed by a stoat.

Lane said DNA evidence also pointed to one of the stoats plaguing the island as being male.

“We are using both male and female stoat scent to attract the stoat into traps. We are also using rodent bedding in some traps,” she said.

“These two animals can harm our wildlife and their arrival on the island remains a real concern for us.”

Stoat dogs would be back on Motutapu and nearby Rangitoto Island from next week, to provide insight on where to redeploy trail cameras and traps.

There is currently a network of more than 400 traps placed across both islands.

“We continue to monitor the situation closely as this island is a crucial habitat for native birds who could be preyed on by this pest,” Lane said.

Although the “incursion response” on Motutapu has been running since December, it took DOC and Auckland Council seven months to wrap up a hunt across three islands, to the tune of $86,000.

A male stoat, weighing close to 400 grams, was found in a trap on Rangitoto on September 25 – months after it was first spotted on another island in March.