A weasel has been found dead in a trap inside the conservation sanctuary at Zealandia in Wellington.
The pest was discovered on Thursday during a routine check of the many traps set as part of Zealandia's biosecurity measures.
Chief executive Danielle Shanahan said the trapped weasel showed its systems were working well, but they would continue to investigate.
"The first step is we go out and we pre-bait all of the other traps that are in the sanctuary ... We don't set them yet. We just get anything that's there used to those traps and then later on this week, we'll set them," she said.
"We take a really careful look at our fence. We make sure there are no remaining ways that animals can get in."
In November, a Department of Conservation mustelid dog will go through the sanctuary to check if it is weasel-free.
As to how this one weaselled its way in, the team at Zealandia was not sure.
"A weasel can get in through a hole the diameter of your thumb. It's quite an incredibly small hole, so it could, for example, be a tree root that's rotten under the fence. So we're doing careful searches to find things like that," Shanahan said.
The last time a weasel was found in the sanctuary was in 2019.
Shanahan said many of the rare taonga species that call Zealandia home had not adapted to deal with introduced predators like weasels, so this was an important discovery.
Weasels can have a devastating impact on native wildlife, because they hunt birds, insects and lizards.
RNZ
