Island Pest Eradications

The Department of Conservation (DOC) and New Zealand experts have led the world in rodent eradications, both locally and abroad.

Breaksea island rat eradication 1985

Breaksea Island rat eradication 1985.

 

Macquarie Island pest eradication 2011.

Campbell Island rat eradication 2001. Photo by P.Tyree

 

Rangitoto Motutapu pest eradication 2009.

Rangitoto Motutapu pest eradication 2009.

 

Eradication is the intentional local extinction of introduced species.

Some of these successes were celebrated at a symposium in 2014 for the 50th anniversary of NZ rodent eradications.One of the first large islands in New Zealand to have rodents (in this case it was Norway rats) eradicated from it was Breaksea Island in Fiordland in 1988 (170ha). The eradication was successful and this paved the way for more ambitious rodent eradication projects.

With each eradication attempt, experience, knowledge and confidence in the techniques used grows and evolves.  Larger and more challenging pest eradications have become possible and significant successful rodent eradications in New Zealand (excluding the Subantarctic region) includes; Kapiti Island (1965ha) in 1996, Raoul Island (2900ha) in 2002, Little Barrier (3080ha) in 2004 Rangitoto-Motutapu (4040ha) in 2009.  A comprehensive list of eradication attempts globally can be found by following this link to the DIISE database.

In New Zealand to date there have been 41 islands where an attempt has been made to eradicate mice. Of these 30 were successful.

On the New Zealand Subantarctic Islands,  DOC has successfully eradicated mice from Enderby Island (710ha) in 1993 and Norway rats from Campbell Island (11300ha) in 2001. One of the conservation aims of DOC is to eradicate all introduced mammalian pests off all the NZ Subantarctic Islands/Ngā Moutere O Murihiku Ki Tonga as resources allow. This long term goal is identified in the draft Conservation Management Strategy for Southland Murihiku 2015 -2025. There are two islands in the New Zealand Subantarctic which still have introduced mammalian pest species present. The main Auckland Island (46,000ha) has pigs, cats and mice and the Antipodes Islands have mice. The eradication of mice from Antipodes Islands is the next logical step.

The eradication of mice from the Antipodes (2045ha) is complex and challenging and the main challenges associated are the remoteness, at 750km south east of the New Zealand mainland, the lack of a harbour for shipping and the typically poor weather of the region. The largest island that mice were successfully eradicated from was 12,875ha Macquarie Island, Australia in 2011. This eradication of mice was in combination with ship rats and rabbits.

Antipodes will be the largest eradication where mice are the sole mammalian pest species. 

Learn more.

Resources:

Database of Island Invasive Species Eradications Read more

Conservation Management Strategy for Southland Murihiku 2015 -2025.draft  Read more

50th Anniversary of rodent eradications in New Zealand Hear more