The Fruit Fly

The Bad: Fruit fly is recognised as one of the worlds' worst economic pests of fruit. An outbreak of fruit fly in an area makes fruit inedible, lowers the profit farmers can make from their fruit, can result in loss of jobs, and prevents the sale of fruit to some interstate and overseas markets.

The Good: At present sterile fruit flies are being released in VIC, NSW and SA to reduce the effect of fruit fly in these areas. Sterile flies can not produce eggs, and therefore stop wild fruit flies from producing young. The sterile fruit flies can be identified as they have been dyed fluorescent pink and glow under ultra violet lighting. This method is more environmentally friendly than spraying chemicals.

The Ugly: Fruit fly maggots tunnel through the flesh of fruit turning it into a brown, filthy pulp.

What to do if you see one: If you find fruit fly larvae in your fruit report it immediately. If you know you have fruit fly in your fruit trees ensure that you pick fruit as it ripens, and place any unwanted fruit in a plastic bag to bake in the sun for a few days before throwing the unopened bag into the garbage.

REMEMBER: Do not take fruit into Fruit Fly exclusion zones. These can be identified by signs on the side of the road.

The Ladybird

The Good: Ladybirds are important invertebrate species as they love to eat aphids as well as a number of other insect species that damage crops. Aphids feed by sucking sap from plants and can spread viruses from plant to plant whilst feeding. When aphids are present in low numbers ladybirds can control their numbers effectively.

The Bad: If sprays of insecticides are used to control aphids, then ladybirds are also likely to be killed.

The Ugly: Ladybirds have four life stages, they are not in the beautiful adult form we commonly see their whole life. Ladybirds start as eggs, are in a larval stage for 2-4 weeks, are in a pupa stage for 5-7 days and then hatch out as adult ladybirds.

What to do if you see one: Look and see if there are any aphids present on the plant that they are on. See if you can find any empty pupal cases that the Ladybirds could have hatched out of.

The Plague Locust

The Bad: Plague locusts feed mostly on grass. In small numbers they do not cause damage. However, locusts can breed very quickly through summer in suitable conditions. A single female can have millions of offspring. In huge numbers, locusts eat any green plant, causing loss to farmers and communities. Victoria invests $350,000 a year to support the control of the plague locust. If locusts were to come to the city they would cause damage to lawns, bowling greens, golf course, parks and gardens and reduced visibility on roads.

The Good: Adults are very difficult and expensive to control with ground spraying because they fly individually at heights of up to 3 m in the day. However, young locusts (Hoppers) move as a "band" or group and can be easily sprayed with insecticides using standard farm spraying equipment.

The Ugly: Adult swarms can cause severe crop damage, including grains if still green. Young vegetables can be completely destroyed, and grape vines can be stripped of leaves, causing grapes to drop.

What to do if you see one: Male locusts are 2.5 - 3 cm long while females are 3 - 4 cm long. If you see a plague of locusts report them immediately. Similarly if you spot a locust egg bed - an area where they have laid their eggs - also report this sighting.

The Honey Bee

The Good: The honey bee is an important invertebrate for the production of honey and for the pollination of plants. Studies have shown that fruit trees which are open to bee pollination produce more fruit than those that are not.

The Bad: Honey bees sometimes form swarms. This can become a problem when bees swarm around houses or schools. A swarm is part of a honeybee colony, including the queen, which leaves the parent colony to establish a new hive. Luckily bee swarms are usually not aggressive as the bees are full of with honey.

The Ugly: Some honey bees are affected by varroa mites, another type of invertebrate. The mites feed on the blood of adult bees and older larvae and pupae. Varroa mites weaken and kill honey bee colonies and can also transmit several honey bee viruses. The life span of bees affected by mites is much shorter than healthy bees.

What to do if you see one: Honey bees have a sting at the end of their bodies so DO NOT TOUCH THIS INVERTEBRATE. It is safe, however, to look at bees from a distance.

The Spider

The Good: The variety of invertebrates found in agricultural areas provides food for several types of spiders. These include ground-dwelling hunters such as wolf spiders, jumping spiders in the foliage and on the ground, and a range of web-spinning spiders. Spiders are useful general predators because they will feed on almost anything that they can catch.

The Bad: Like most invertebrate species found in agricultural areas spiders are susceptible to insecticides used to kill pest species. When spraying chemicals to kill pest species this will also kill the beneficial spiders.

The Ugly: Spiders poison their prey and then suck out the body contents without consuming the whole body.

What to do if you see one: The bite of some spiders can cause pain and illness. If you see a spider it is best to leave it where it is and simply look at it.

The Diamondback Moth

The Bad: The diamondback moth is the most destructive insect pest of brassica crops throughout the world. Brassicas are a group of plant species that include many common vegetables such as brussels sprouts, cabbages, cauliflowers and turnips. The caterpillars of diamondback moths eat many small holes in the leaves of these plants and tunnel into vegetables, making them unsuitable for sale.

The Good: Some predator insect species and wasps can help control diamondback moths. In addition by ensuring that crops are checked regularly and the appropriate chemicals are used to control this species the damage caused can be minimised.

The Ugly: A female moth may lay more than 150 eggs during her lifetime, this means that a single moth can produce many caterpillars. In addition diamondback moths have developed a resistance to many insecticides, and as a result they are hard to control.

What to do if you see one: If farmers observe the diamondback moth or caterpillar in their crops it is important they take action immediately to control the species to ensure their whole crop is not affected and unsuitable for sale.