Breaking the life cycle

Queensland fruit fly population build-up occurs from early spring. The level of fruit fly activity increases across the region as flies that were able to survive winter as adults begin to leave winter refuges and infest fruit. If these flies can be controlled over spring, then later spikes that damage summer and autumn crops, will be reduced.

The below controls are recommended to limit spring activity and help reduce numbers over summer:

• Control adult flies active in spring by using baits and traps
• Stop adults from infesting fruit by removing fruit as it ripens – pick up and harvest unwanted fruit
• Protect fruit using netting

Early signs of fruit fly

It is important to start monitoring now and take action at the first signs of fruit fly.

• Inspect ripening and ripe fruit regularly
• Use fruit fly traps to detect fruit fly activity

Trap information

Traps can be purchased from nurseries and home garden stores or you can make your own.

Male-targeting traps – are the most common trap and contain a pheromone-like attractant that only males respond to. Providing weather conditions are suitable these traps can attract male fruit fly from up to 200m, but if it is cool or windy, as it often is during spring, they are less effective at such distances.

Food-based traps – several traps that are relatively new to the market attract both male and female fruit fly using food-based compounds such as broken-down yeast cells (yeast autolysate) and synthetic fruit aromas as attractants. These traps are effective at much smaller distances and need to be within 10m – 20m to active locations.

Food-based traps are useful as they can capture females. In her lifetime, which is about 2 months in late spring to early autumn and much longer in the cooler weather, one mated female Queensland fruit fly can lay nearly 2,000 eggs from which up to 800 adult flies can emerge.

Extra vigilance required

Regional trapping data for spring 2021 and autumn 2022 showed that several locations recorded high populations during this period. This suggests fruit fly will be problematic in those areas in the coming 2022/23 season. Extra vigilance is required in the following areas:

• Kyabram
• Grahamvale
• Merrigum
• Undera
• Shepparton
• Orrvale

If you live in or near these locations, use monitoring traps and check nearby ripening, ripe or overripe fruit within the vicinity for the presence of fruit fly.