Every Tuesday morning, pilot John Williams takes two million passengers on a flight from Echuca to Cobram in Victoria.
He doesn’t even land in the Goulburn Murray Valley township — he drops them off mid-air.
- A trial project releasing sterile fruit flies resumes in Cobram for its third and final year
- Results are showing a reduction of fruit fly numbers in the area
- Researchers are expecting perfect conditions for fruit flies to breed this summer
The passengers are sterile male fruit flies, released to help reduce numbers of the growing pest in the horticulture region.
Cobram produces around 87,000 tonnes of fruit and vegetables annually and is a trial site in a three-year project being led by Macquarie University.
Mr Williams said he started his Tuesdays in Tocumwal in New South Wales before heading to Echuca to pick up the flies.
“We were taking the fly out of Shepparton, but due to lockdown and COVID we had to change the pickup.
“A delivery from the Tatura Department of Agriculture, bring them up to Echuca, we load them into the designated fly box refrigerated at 4 to 5 degrees Celsius.
“No landing in Cobram; we just hook the plane into the designated tracks and then I head back to Tocumwal when I’m done, and that’s my Tuesdays.”
Mr Williams said the program worked similarly to aerial crop spraying, with GPS coordinates lined up with a map of where the flies needed to be released.
“The flying is the simple part, it’s the computer operation that I had to step up to,” he said.
“The computer has tracks that I have to follow, they are about a mile long and about 200 metres apart. It’s a very controlled system.”
Mr Williams will do this flight over Cobram every Tuesday until April.
Numbers are decreasing
This is the third year of the sterile Queensland fruit fly release across Cobram, which is part of the Hort Innovation-funded Post Factory Pilot of SITPLus Fly Production Project.
The project is also being undertaken in Hillston in New South Wales.
Bishwo Mainali, a research fellow from Macquarie University, said the weekly release of two million flies had greatly decreased the local Queensland fruit fly population in areas like Cobram.
“We have two sites: one is Cobram township which receives sterile flies, and the other site is Mooroopna which doesn’t receive any flies,” Dr Mainali said.
“The two townships are very similar in climate, so when we release flies in Cobram, we compare them to the control site in Mooroopna.
Dr Manali said the continuation of the program would come down to government funding.
“The main goal of the project was to demonstrate that sterile flies can suppress the population of wild flies, and we have been able to produce that.
“It depends now on the government to take this forward. I’m not in a position to say what will happen right now.”
Dr Mainali said eradicating Queensland fruit fly from the area could be achieved with programs like the sterile releases working alongside community management programs.
Every little bit counts
In 2016, the Goulburn Murray Valley Regional Fruit Fly Group was activated to strengthen fruit fly management between growers and the community.
The program works with the sterile release program by monitoring a trapping grid that covers local orchards.
The program also works with the community to manage fruit flies in backyard gardens.
Program coordinator Ross Abberfield said it was essential to target the urban areas early.
“Fruit fly tend to emerge from winter and they are first detected in urban areas,” he said.
Cobram fruit grower Adrian Conti said it was a combination of all these projects that helped protect his business.
“Fruit fly is one of those difficult pests that we have to be careful to have our strategies in place, because we have lots of export markets that we want to send our fruit to.”
He said the role of the community was important in controlling this pest.
“We’ve always had the opinion that fruit growers can look after their own patch, so to speak, but with the help of home gardeners in urban areas, it stops flies from breeding up and getting out of control before it gets out to commercial orchards.
“Every little bit helps — spraying, netting, removing trees and the sterile fly release have all been good.