Rats and mice can stow away on visiting vessels and escape onto islands so it’s important to check your boats, kayaks and gear for pests before you head into the park. Even if you don’t land on any of the islands, rats and mice can swim if you moor nearby. Some predators can even swim from the mainland.
The islands do have measures in place to counter invading predators, including traps and tracking tunnels to record footprints, but we need your help to keep them predator free.
Rats are a threat to South Island robins/toutouwai and saddlebacks/tīeke that have been returned to Adele Island and to robins that have spread to Fisherman Island. Rats and mice threaten insects and lizards and, as they also eat seeds, they suppress re-vegetation. Mice can even eat small birds’ eggs and nestlings.
The islands first became predator-free wildlife sanctuaries in 2007 but mice were found back on the islands in 2015 and 2020 when pest numbers were high in the park, due to a heavy beech mast. During a beech mast there is abundant food which fuels breeding and rodent numbers.
In 2020 a mouse eradication was completed on Motoureronui/Adele Island. The island will not be able to be declared officially mouse-free until March 2021.