Unmanned aerial vehicles are taking off to make pest control more targeted, safer and less invasive.
As climate change increases the risk of invasive pests affecting New Zealand’s multibillion-dollar primary sector, Scion researchers are hopeful the tool will provide a more efficient biosecurity solution.
Scion’s plant protection physics and chemistry team lead Justin Nairn said using unmanned aerial vehicles (UAVs) could be a new tool in the biosecurity toolbox making pest control more targeted, safer and less invasive.
UAVs can fly closer to the target than a helicopter, coming within about 2m versus more than 10m, have a smaller footprint and fly more slowly, meaning they can be more precise.
The research comes two years since the discovery of fall armyworm in NZ in February 2022. The moth threatens crops in its larval stage.
Nairn’s initial studies in March 2021 into the general efficiency of spraying using UAVs worked with fluorescent dye to investigate how they performed in aerial spray operations.
In February last year, one year after fall armyworm’s arrival, scientists trialled a key bio-insecticide for combating Lepidoptera moths.
The findings of this trial are still being finalised, but Nairn said using UAVs for pest control is growing quickly as operational limitations such as cost, weight and flight time are reducing in the face of technological advances.
Scion has been involved with pest incursion responses and field research in aerial spray methodology for decades, looking for new, more targeted ways to tackle pest and insect outbreaks.
The invasive pest problem has been highlighted many times over the years, from a seven-year, $65 million response to the painted apple moth in Auckland in 1999, through to the ongoing battle against fall armyworm and managing myrtle rust.
Scion social scientist Andrea Grant said fast and effective pest control is vital to prevent pest and pathogen establishment.
However, she said, there needs to be a balance between engaging communities ahead of incursion responses and the potential need for fast action.
“If community concerns are not addressed and they have no opportunity to respond to planned operations, they may lose confidence and support for urban biosecurity operations in future.”
In aligned research, Grant ran focus groups looking at social and cultural considerations of UAV spraying.
These groups included social researchers, UAV researchers, Māori involved in forest protection and management, and forestry managers.
Participants identified social issues such as human health, safety and ethics, professionalisation of UAV use, Te Tiriti partnerships, engagement and capability.
Grant and her collaborators also held a co-design workshop where participants noted the role for mātauranga Māori and need to work with Māori alongside key agencies in research, policy, operations and ethical aspects of co-design.
Māori environmental not-for-profit Te Tira Whakamātaki was included in the focus groups.
Chief scientist Simon Lambert said much of the Māori economy is in the primary sector and therefore highly reliant on the environment.
“Māori are increasingly aware of the vulnerability of their assets and cultural capital to biosecurity events and are not opposed to technological innovation but insist on early and ongoing engagement,” Lambert said.
Better Border Biosecurity (B3) director Desi Ramoo said Nairn’s research is an example of adapting existing technology into an applied biosecurity tool. B3 is a multi-partner joint venture researching ways to reduce entry and establishment of new plant pests and diseases in NZ.
“We must be prepared with a number of solutions developed from Western science and mātauranga Māori to ensure we are ahead of the game and move from a reactive to proactive biosecurity system.”
Forest Owners Association biosecurity manager Brendan Gould said successful intervention relies on the ability to respond, but community impacts and implications need to be considered as part of the process of operational design.
“There is no one tool that will work in every situation.”
Gould said engagement before an incursion is important but challenging when immediate action is needed. Scion’s research allows for pre-engagement to be considered.
Nairn’s research work was part funded by B3 while Grant’s was part funded by Forest Growers Research Trust. Both received Strategic Science Investment funding.
