The first-ever trial using sterile male fruit flies dropped by aircraft to control the Queensland fruit fly population has been described as a resounding success.
- Sterile male fruit flies are dropped and then mated with the female fruit flies
- The fruit fly releases contributed to an 83 per cent reduction in Cobram
- The trial is a first, and will test the accuracy of the results over the next two seasons
The trial called SITPlus Pilot was part of a Hort Innovation Project and towns in Victoria and New South Wales, which had Queensland fruit fly populations, were used in the program.
Sterile male fruit flies raised in a facility in South Australia were dropped over Cobram in Victoria and Hillston in New South Wales between September last year and April this year.
Results better than expected
The weekly flights on a light plane meant that large numbers of sterile male fruit fly were dropped and then mated with the female fruit flies resulting in big changes to numbers of flies.
“The trial achieved results better than we expected and there was a noticeable drop in Queensland fruit fly populations in both areas,” according to Dan Ryan from Hort Innovation.
“People who lived near the town of Cobram were able to eat fruit from their backyard fruit trees for the first time in many years and were happy with the trial,” Mr Ryan said.
The Regional Fruit Fly Controller for the Goulburn Murray River Valley Ross Abberfield said the timing of the project fitted in with their area-wide management activity.
“This includes the removal of feral fruit trees, abandoned orchards and neglected urban trees on both public and private land,” Mr Abberfield said.
“All up we have seen a reduction of 57 per cent in the activity of Queensland fruit fly in the area because of that management program,” Mr Abberfield said.
Accuracy to be examined
Stage two of the SITPlus Pilot Program will begin in mid-September and will continue right through until April 2021 using a light plane to drop the sterile flies.
“The Queensland fruit fly is a native fly but is not native to areas in Southern Australia like Cobram and Hillston and the aim is to control the fly expansion,” Mr Ryan said.
“This trial is a first, and we need to test the accuracy of the results over the next two seasons to make sure we know it works effectively,” Mr Ryan said.
A number of states including Tasmania, which is a fruit fly free location, are funding the SITPlus Pilot and are watching the results closely.
An outbreak in Northern Tasmania and on Flinders Island a couple of years ago led to fruit fly zones being established causing major headaches for fruit growers in those areas.