Duration and setting
Five hours spread over a number of weeks in the classroom and school grounds.

Summary
This activity enables students to investigate the impact that Queensland Fruit Fly (Bactrocera tryoni) has on communities in Victoria. Students will capture and observe non-pest fly species such as the Vinegar Fly (Drosophila melanogaster) to observe their life cycles. These observations can then be used to understand constraints in managing Queensland Fruit Fly in Victoria. Students will then design, conduct and report on simple experiments, and assess what they can do to minimise the impact of Queensland Fruit Fly.

The activity

Part A: Literature review
When undertaking a scientific investigation the first step that any scientist must take is a literature review - a review of the current knowledge and research about their proposed area of study. Students can do this by finding out three facts about fruit fly using the Queensland Fruit Fly Fact Sheet or the internet. Facts about Queensland Fruit Fly could fit under the headings: Description/Identification; Diet; Life Cycle; Impact; Monitoring and Control; and Prevention. As a class collate the information on a poster or wall chart, share these facts to develop an understanding of current knowledge regarding the species.

Part B: Capturing Vinegar Flies
One activity that is undertaken to control Queensland Fruit Fly in Victoria is the use of traps to detect flies in horticulture areas; then to capture and destroy them. Building a fly trap is therefore a fun and effective way to enable students to relate the difficulties and successes they experience in designing and capturing Vinegar Flies to those experienced by scientists in the field. It also enables students to observe a species with the same life cycle as Queensland Fruit Fly.

Vinegar Flies can be found around compost bins, near rotten fruit under trees and sometimes even in supermarkets. This species is much smaller than the Queensland Fruit Fly and generally only attacks fruit that has been damaged. It therefore does not pose a risk to the fruit industry. However, should you capture a fly which looks like the Queensland Fruit Fly please report this immediately to the Department of Primary Industries on 136 186.

To run this activity, divide the class into pairs. Hand out the 'Building a Vinegar Fly trap' instructions and materials to each pair of students. Consider what time of year you run this activity as fruit flies are most active, and therefore easiest to capture, in warm weather. It should only take one day to capture a number of flies. See 'Building a Vinegar Fly trap' for full instructions. Once they have captured their flies, students can develop presentations, plays, posters, or short story books detailing the life cycle of the Vinegar Flies (ie. egg - larvae/maggot - pupae -fly). Students may wish to share these with students in a younger class.

Part C: Fruit fly investigations
Once students have captured Vinegar Flies, and observed their life cycle, it is possible to undertake a number of experiments using the flies and fly traps. Encourage students to think about different issues involved in fruit fly management in Victoria and Australia and to develop a question they wish to investigate relating to trapping of the species. Students can then design, conduct and report on their investigation using the suggested format: Project Title; Student name; Introduction to the issue; Objective of the investigation; Question being investigated; Materials required; Methods used; Results; and Conclusion.

Some example questions/hypotheses that they could investigate include: Will fruit flies be more attracted to a real banana or a synthetic banana? Do fruit flies have food preferences? and What effect does temperature have on fruit fly life cycles?

Part D: Fruit fly reflections
Encourage students to think about the role they play in the management of fruit fly in Victoria. Ask students to line up along an imaginary line. At one end are excellent fruit fly fighters; at the other are those spreading fruit fly throughout Victoria. Discuss with students why they have stood where they have on the line, what have they been doing to fight fruit fly, and what have they may have been doing to help it spread. Next ask students to take one step towards the fruit fly fighting end of the line. Ask students to think about what they would have to do in their lives to be more effective as a fruit fly fighter. Follow up with this activity at a later date to discover what action has been taken by students to fight fruit fly.

Building a Vinegar Fly trap

What do I need?
Two litre plastic bottle, film canister or small container that fits in the base of the bottle, masking tape, scissors, rotting fruit or vegemite or golden syrup.

What do I do?

»	Cut the top off the bottle and tape the film canister to the bottom of the bottle.
»	Place some rotting fruit in the film canister and tape the top of the bottle back on upside down with the lid removed.
»	Place your trap outside near fruit trees or bins (hang your trap to prevent ants crawling in). Vinegar Flies will enter the trap, however it is easier for the flies to fly into the trap than out of it and they will become trapped!
»	Once captured place a piece of cloth over the bottle opening, secure with a rubber band, and place in a warm position (22°c is optimum). Observe the life cycle of the flies (it only takes 2 weeks), females in the trap will lay eggs, and in a few days they'll hatch. Observe the different stages, eggs, larvae, pupae, fruit flies.
»	Experiment with the fruit bait that you use. Some suggestions include banana, melon, apple and pear. A mixture of vegemite, water and golden syrup is also good. See if you can come up with your own mixture!

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Fruit fly larvae in an orange