Molecular level pest control

Research on invasive mammals is changing gear and increasing resolution to a molecular level never attempted before in New Zealand.

The approach, which will apply cutting-edge technology and techniques similar to those already used in medicine, is expected to help improve the long-term precision, scale and effectiveness of pest control.

The molecular level on which pest control research will focus via The High-Tech Solutions to Invasive Mammal Pest Project will play a huge part in reaching the goal of Predator Free New Zealand 2050, says project lead University of Auckland scientist James Russell.

He says pest control today relies on technology and strategies from the early 20th century that fall well short of what the country needs to achieve predator free status within the next three and a half decades.

“We really want to speed up the process by which we can apply some of the very precise molecular-based technologies developed in the last stages of the last century to deal with mammalian pests,” James says.

This will include finding out as much as possible about what makes a brush-tail possum tick by sequencing its genome and then using the information to find weaknesses within it to develop a species-specific toxin.

“The possum is a uniquely New Zealand pest so little work has been done to map its genome,” James points out. He says because marsupials are already quite different from placental animals, sequencing the genome will be somewhat more straightforward.

A molecular approach will also be used to deal with rodents. Although a lot of work has already been done internationally to sequence rodent genomes, New Zealand researchers plan to tackle a missing piece of this research by looking at ways of “delivering infertility” throughout a rodent population.

Ultimately, James says, its not going to be enough to just find a way of making a genetic trait change that renders an animal vulnerable. Researchers will also have to find a way of delivering this trait throughout a population to the point where the end result is complete eradication.

Research will also tweak some of the more traditional methods such as trapping by using the latest technology to fine-tune the kind of lures used to attract stoats. The project will use gas chromatography to find exactly what chemical within a specific lure is attractive to stoats.

“Previously we might have compared peanut butter with chocolate as a lure, but we now have technology to analyse exactly what chemical aroma within chocolate they like and then synthesize and use this to improve the chances of a stoat going into a trap and not coming out,” James says.

Another piece of the pest control puzzle will be to develop a cost effective molecular-level technique that can tell us just how effective a control operation has been and how many/if any pests remain.

Andrew Kralicek’s work will look at powerful biosensors in wireless networks that are triggered by the species-specific molecules given off by a particular pest species when it gets close to a sensor. This technology could have applications well beyond pest control, for example biosecurity checks in shipping containers on arrival into the country.

James says a key component of the Challenge-funded $1.5 million research project is consultation and input from Maori at every stage of the research and throughout the development process to ensure that their views, concerns and input are acknowledged and incorporated as progress is made.

“The important thing is that we have all the key people who have been working in pest control over the last few decades working together, pooling their knowledge to achieve the step change we need to achieve eradication at the scale needed to protect native biodiversity,” James adds.

In the background, as all this research is taking place, James will also look at what needs to happen when a research breakthrough takes place. “We will need to know exactly how to introduce a new control, what level we should apply and set benchmarks on what we need to achieve,” he said.

James uses an example of someone discovering a new headache medicine. “If a new product for a headache is discovered, developers would need to know whether it is better than an existing product.”

In the case of pest control techniques, James says the question will also be whether something should be introduced straight away, or whether it would be better to develop it further for better results down the track.

“We also need to make sure that people who will end up using the tool support it,” he adds, so will be considering the broader societal implications through a bioethics panel.