The Department of Conservation (DOC) says New Zealand’s native moths and butterflies are facing mounting challenges, with 60 years of world-leading evidence pointing to significant species declines in the eastern South Island.
An independent panel of experts has assessed the conservation status of 498 Lepidoptera (moths and butterflies) species, in a new report published by the Department.
Since the previous moths and butterflies assessment in 2015, 35 species have deteriorated in status, with six of those moving to Threatened – Nationally Critical (the last category before extinction). Although another 19 species have improved status, this is due to more knowledge rather than genuine improvement.
Panel member and DOC Senior Science Advisor, Eric Edwards says the 60 years’ worth of evidence in a moth study from Canterbury is rare worldwide, providing relevant insights into moth population trends.
“The 60-year record shows an 82% decline of moths in the two Canterbury sites between 1961 and 2021. This result is compelling and is worrying evidence of serious moth declines,” said Mr Edwards.
“Unfortunately, this trend of a decline in moth species is likely to be ongoing in many other parts of New Zealand and around the world.”
The panel found that the biggest pressures on moths and butterflies come from changes to their natural habitats, caused by invasive plants and animals, as well as the growing impacts of climate change in recent decades.
“Among more naturally open areas, particularly the eastern South Island, habitats that historically hosted native moths are being outcompeted by exotic grasses, exotic broom and wilding pines,” Mr Edwards said.
“Invasive animals are a problem too. Wasps are eating moth and butterfly caterpillars. More research is needed to better understand the seriousness of wasps and other invasive predators like mice.”
However, it’s not all bad news for moths and butterflies, with exciting discoveries being made.
“A Swedish tourist’s rediscovery in 2024 of the large and striking frosted phoenix moth was a sensation. Since then, several sightings have been reported in Rakiura, Little Barrier Island and Pureora Forest Park. These sightings are largely thanks to the use of ultraviolet LED technology, which works in damp weather when frosted phoenix like to fly,” said Mr Edwards.
He said there are community groups and private landowners taking pest plants seriously, which is vital for the restoration of moth habitat.
“Citizen scientists are also making a difference. In the last few years, members of the public have used their mobile phones to record and upload vivid and detailed images of secretive and rare moths and butterflies to the iNaturalist app, increasing local knowledge.”
Anyone can become a citizen scientist by downloading iNaturalist NZ app at: A Community for Naturalists · iNaturalist NZ.
“Recording your sightings of moths and butterflies helps scientists, environmental agencies and community groups to better understand New Zealand’s Lepidoptera and plan restoration work.”
“Other naturing activities that everyday people can do include plant nectar species as food for moths and butterflies, get rid of invasive weeds, and control exotic wasps,” Mr Edwards said.
Visit DOC’s website to read the report: Conservation status of Lepidoptera (moths and butterflies) in Aotearoa New Zealand, 2025.
