Autopsy results have been released on the dead rat that was found on Mokoia Island.
The Department of Conservation (DoC) said the vermin was confirmed as a female Norway rat - also known as a common brown rat. The species is known to be good at swimming, both on the surface and underwater.
Weekly checks of the trapping lines is still underway with DoC, Mokoia Island trustees and volunteers since the rat was discovered in a trap two weeks ago.
"'It would appear the trapping lines worked in exactly the way we wanted them to - preventing access to the inner island by detecting pests relatively soon after they have arrived on the island," senior biodiversity ranger Erin Patterson said.
"A rat detecting dog has covered the island and provided no further signs of pests are discovered in the next two weeks, we will return to monthly bio-security checks"
