A problem with mice infestations that goes back to whalers and other early ships visiting Antipodes Island in New Zealand’s SubAntarctic region is now over.
Conservation Minister Eugenie Sage said this was achieved with the Million Dollar Mouse project - a joint initiative between the Department of Conservation (DOC) and funding partners the Morgan Foundation, WWF-New Zealand, Island Conservation and public supporters.
“Special plants and wildlife, including 21 species of breeding seabirds, more than 150 species of insects – 17% of them only found on the Antipodes; 21 uncommon plant species and four unique land birds are found on the Antipodes Island,” Ms Sage said.
“They can now thrive with mice no longer preying on the insects or competing with the land birds.”
The Minister visited Antipodes Island aboard the HMNZS Wellington in February when the outcome monitoring team were dropped off to review whether the winter 2016 baiting operation was successful.
During the visit, she saw first-hand the challenges the project faced, including remoteness, scale, and difficult terrain.
“Seeing so many Antipodean and Reischek’s parakeets, pipits and insects flourishing on what is now a predator-free island is a tribute to the ambition, planning, dedication and skills of everyone involved from the helicopter pilots and bait crews in 2016 to the monitoring team this year.”
Led by DOC’s Finlay Cox, the monitoring team searched the island for almost a month and found no sign of mice. They were assisted by three rodent detecting dogs from the Conservation Dogs programme, supported by Kiwibank and Auckland City Council.
DOC project manager Stephen Horn said work started on the project in 2014, but planning started much earlier.
“This success is not down to any single organisation or country and thanks must go to everyone involved, particularly the NZ public. Their donations and belief in the outcome got this project off the ground.”
The Antipodes Island group is about 760 kilometres south east of New Zealand. The 2,100 hectare islands are protected as a Nature Reserve and recognised internationally as a World Heritage site for their outstanding natural values.
Antipodes Island had a large mouse population of about 200,000. House mice eat invertebrates, prey on bird chicks and eggs and also eat plant material including seeds.
This competition for resources and predation had altered the biodiversity of the Antipodes islands. Mice had already wiped out two taxa of insects from Antipodes Island. Additionally Black-bellied storm petrels and subantarctic little shearwaters only breed on the mouse free offshore islands.
Mice on Gough Island and Marion Island in the South Atlantic have been recorded killing large seabird chicks by literally eating them alive on the nest.
DOC successfully eradicated cats and rats from Great Mercury Island in the Hauraki Gulf in 2014 and eight different mammalian pests were eradicated from Rangitoto Motutapu Islands in 2009, including rats, mice, cats and stoats.
In the SubAntarctic DOC previously eradicated rats from Campbell Island in 2001. In the Auckland Island group rabbits and mice were eradicated from Enderby and Rose Islands in 1993 and a small population of goats were eradicated from the main Auckland Island by 1992.