This is the third in a series of bi-annual newsletters sharing updates on the progress, team, and unexpected discoveries from this research programme.

New Zealand faces ongoing risks from insects and pathogens blown here on the wind—an often-overlooked gap in our biosecurity defences, and one likely to grow with climate change. The Protecting Aotearoa from Wind-Dispersed Pests programme is addressing this challenge over the next five years by improving knowledge of in-transit pest survival, updating wind models, and tracking how and when organisms move through the air. The goal: a predictive warning system to help us respond faster and more effectively.

About 150 students took part in hands-on learning, focused on the vital role biosecurity plays in protecting Aotearoa’s forests and landscapes. They explored the science behind pest detection and management, learning how wind-dispersed pests threaten native ecosystems and how researchers are developing innovative tools to detect and respond to these risks.

The students’ enthusiasm was unmistakable. More than 30 thank you notes arrived in the weeks following the event, filled with personality, curiosity and appreciation. Their messages are a powerful reminder of the lasting impact science outreach can have in inspiring the next generation of environmental guardians.

"Thank you again for making science interesting."

"Something funny I remember is going to two stations before going to the right one. Thank you for teaching us everything."

How moths and butterflies reach Aotearoa – and why it matters

Mike Davy & Toni Withers

One of the unique ecological aspects of Aotearoa is our isolation from the rest of the world. The distance provides us protection from biosecurity threats and prevents regular dispersal by all but the most capable migrants. Of our 1,700+ Lepidoptera species (moths and butterflies), 87% are found only in New Zealand, while the remaining 13% are considered non-endemic.

What are we likely to get?

Using data from published literature, government reports, and iNaturalistAU, we have compiled a database containing key features of our non-endemic Lepidoptera to find trends associated with establishment in New Zealand through the aerial pathway. So far, we have found that non-endemics associated with this pathway tend to have larger wingspans, a recorded history of long-distance dispersal/migratory behaviour, and have a high number of observations on iNaturalistAU.

After an initial look into the most abundant moths on iNaturalistAU, we quickly identified three commonly observed migratory species with decent wingspans, that pose a risk to our pasture and/or crop industries. These include the sugarcane looper, the lawn armyworm, and the southern armyworm, which have been spotted on our shores before, but none are known to have established yet. Given enough time, species like these may get multiple opportunities to ride along air bridges, perhaps in high enough numbers to establish successfully in Aotearoa. We’d best be prepared.

Where did they come from? 

About 65% of our non-endemic Lepidoptera originate from elsewhere in Australasia, and most others from Europe and/or Asia. In addition, an incredible 91% of our non-endemic Lepidoptera are present in Australia, regardless of their native origin, making presence in Australia one of the best predictors of invasion risk to New Zealand.

How did they get here?

This question is much harder to investigate without the use of a time machine. We are unsure about how around half of our non-endemic Lepidoptera arrived in New Zealand, but at least 11% are thought to have been accidentally imported here via ships or planes. This pathway has tightened up a lot over the past few decades, with surveillance efforts targeted around ports and airports.

The other major pathway is the aerial pathway, whereby moths, butterflies, and other organisms disperse to Aotearoa through the air, facilitated by large atmospheric structures called ‘air bridges’. For at least the past 100 years scientists have suspected moths and butterflies use this pathway, so it’s not a new theory. However, it is still highly relevant today as there are many Lepidoptera present in Australia that we do not want here. Approximately 25% of our non-endemic Lepidoptera are thought to have blown over with prevailing winds from Australia. When teasing out our non-endemic species into macro-Lepidoptera (newer lineage, typically larger), and micro-Lepidoptera (older lineage, typically smaller) we find that an astounding 71% of the macro-Lepidoptera and only 5% of the micro-Lepidoptera have come to Aotearoa on the wind.

New discoveries on Taranaki Maunga: a win for native moth research

Toni Withers

While surveying Taranaki Maunga for migratory macro moths that may have flown in from Australia, our research team continues to uncover exciting new information about native species.

Researchers have recently confirmed the presence of a rare native moth species, Ichneutica dundastica, on Taranaki Maunga. Both a male and a female were collected during night-time light trapping. This species was first described in 2019 by Dr Robert Hoare and, until now, had only been recorded in the Tararua Ranges in the Wellington region. Ichneutica dundastica typically lives in alpine shrublands, and very little is known about its host plants or life cycle.

Identifying moth species like this is no easy task. After fieldwork, researchers bring a selection of specimens back to the lab. There, they carefully spread the wings, photograph the moths, and upload the images to our Wind Wanderers iNaturalist page. Expert lepidopterists Dr Robert Hoare and Neville Hudson then step in to help with identification. It can be a challenge—especially with groups like the “owlet moths,” which often have very subtle differences in their wing patterns.

This is our second exciting discovery – in our previous newsletter Blown Away 2, we reported the discovery of a native carpet moth—Tatosoma monoviridisata found on the Maunga for the first time. Each new discovery is a cause for celebration. Sean Zieltjes, Poutohu Matua Taurua / Co-Project Director of the Taranaki Maunga Project, says it’s great news:

“It's helping deepen our understanding of the rich biodiversity on Taranaki Maunga. We look forward to hearing what the next moth survey brings."

Our work on the Maunga continues, and with each survey, we’re learning more about the incredible and often hidden biodiversity of this iconic landscape.

Taking flight: learning to track moths in Australia

Toni Withers

In June, our PhD student Lorenzo Orlando (University of Canterbury) and programme co-lead Dr Toni Withers travelled to Townsville, Australia, for a hands-on research visit to the insect behaviour lab of Dr Myles Menz at James Cook University. Dr Menz has dedicated his career to understanding insect flight and migration, from tracking hawk moths in the European Alps with radar and tiny tags, to studying hoverflies on long-distance journeys.

During the visit, Lorenzo and Toni learned the latest techniques for studying moth flight in the laboratory. These skills will support Lorenzo’s PhD research on pest species such as the Armyworm moths, known to be strong fliers and serious agricultural threats. By testing moths under different environmental conditions and measuring their energy use in flight, he aims to uncover how factors such as rainfall and reduced air pressure—similar to those experienced high in the atmosphere—affect their performance during migration.

We are deeply grateful to Dr Menz for sharing his expertise and for hosting such a valuable learning opportunity. This visit has strengthened our research and laid the foundation for future collaborations.