Fruit fly traps can be divided broadly into three groups: monitoring; mass trapping; and liquid protein trapping. With the range of products commercially available there is some overlap in these groupings.
Mount Alexander Shire Council and the City of Greater Bendigo, in partnership with Agriculture Victoria, produced a series of educational videos on managing Queensland fruit fly. This episode covers trapping.
Monitoring traps are simply containers which fruit flies can enter, but which they cannot easily escape from. When combined with a powerful lure (parapheromone), male fruit flies will be strongly attracted into the trap and this will let you know when fruit flies are active. The numbers of flies caught will give you some indication of the level of fruit fly activity, but should only be considered as a guide.
The main management advice provided by traps is an awareness of whether fruit flies are active in your orchard and whether it is time to commence other fruit fly management activities.
As a general rule, monitoring traps are deployed at a low rate, often only one or two per hectare or per orchard block. Some types of these traps are also used to monitor and verify that a pest free area truly is pest free.
There are a variety of traps available on the market, including the Lynfield (used primarily for fruit fly pest free area monitoring), the Bugs for Bugs Fruit Fly Trap, Bio-Trap, and the Susbin trap. Forms of stick traps like Jackson traps and the Fruition trap can also be used for monitoring fruit fly activity.
Mass trapping can use the same traps as monitoring, but deployed at much higher rates. The theory behind this approach is to attempt to catch as many active flies as possible. However, it must be remembered that the lures used in many traps are specific to male fruit flies and the damaging egg laying females flies will be unaffected. Therefore, mass trapping must be used in conjunction with other proven techniques such as protein bait sprays. Mass trapping for male flies is also similar to another control methods, the Male Annihilation Technique (MAT).
Some fruit fly traps are able to be use a female attracting compound. Bio-Trap also supply a fruit fly attractant gel that attracts both male and female fruit flies. The Fruition trap used a lure sachet and visual cues to attract fruit flies.
Liquid protein traps
Liquid protein traps can be used in some cases for monitoring in pest free areas, but their main use is to capture female fruit flies. They target the female fruit fly’s need to feed on protein in order to develop their eggs to maturity. By using a protein attractant, recently emerged female fruit flies will enter the trap, get caught, and eventually drown. There is a range of different traps and lures, and it is also possible to make these at home. The main shortcoming of liquid protein traps is that they tend to have a limited range of attraction. Commonly these traps will be placed at a 5m interval around the perimeter of an orchard.
- Trapping will help you understand when fruit flies first become active in your region and when to start using control measures
- Trapping provides a direct visual sign of fruit fly activity and can capture newly emerged flies before egg-laying has commenced
- The contents of traps do not contact your tree or fruit so there are no concerns about chemical residues
- Traps are generally easy to maintain.
- A range of traps are available, including both cheap options and more durable options
- Most (but not all) traps are specific to fruit flies so you will not impact on beneficial insects.
- Traps, whether used for monitoring or mass trapping are not a complete solution. You will need to use a range of methods
- Traps do not provide quantitative information on fruit fly activity
- Other control methods can influence trap captures
- Liquid protein traps require regular maintenance, generally replacing or topping up the liquid weekly.
What traps are right for your situation?
Fruit fly monitoring traps should be deployed as part of an integrated pest management approach and to help you identify whether fruit flies are active in your area. The use of mass trapping or female fruit fly traps will depend on the fruit fly pressures in your area.
Factors affecting success
- Fruit fly traps need to be placed between 1.5 and 2m and on the eastern or north-eastern side of the tree out of direct sunlight
- Trap lures need to be replaced on a regular basis, generally every three months
- Correct choice of lure for the fruit fly species in your area