Rude awakening in store for Australia locusts
Copyright 2000, Environmental News Network
December 5, 2000
By Nick Goldie
Locusts migrating in plague proportions can cause enormous losses to grain producers.
Australia faces the largest locust plague ever recorded in the country, warns the Australian Plague Locust Commission. But the insects may be in for a rude shock.
For the first time in recent history, locusts threaten agricultural production on both sides of the continent in the same year.
Western Australia is facing the largest plague ever, South Australia the largest since 1955, and New South Wales and Victoria the largest in 10 years.
"An intensive control effort will be needed to avert major crop and pasture damage," says Graeme Hamilton, head of the APLC.
Due to the extent of the infestation, the APLC will only be able to treat those areas where aerial control is most needed. Extensive ground control of locust bands by landholders and others will be essential in order to prevent a major plague from developing.
"We will have to throw everything at the locusts this time, and we have been working all year with state agricultural departments and farmer groups to plan our defensive strategy," says Hamilton.
"We are fortunate that CSIRO's new metarhizium-based biopesticide Green Guard has been given a special permit by the National Registration Authority to be used in widespread operational trials," he adds.
Metarhizium is a naturally occurring fungus that infects and kills locusts and other pest insects.
"A major boost for our armory, and a surprise for the locusts, is that it can be used in environmentally sensitive areas, and on some organic farms where other agents can not."
Hamilton says that large-scale hatchings are expected in western and southern New South Wales, northern and central South Australia and north-western Victoria. In Queensland, widespread hatchings may occur in the Channel Country where conditions were ideal for breeding. In Western Australia, hatchings from in a wide band from Moora to Esperance threaten the wheat belt and other agricultural areas.
The true extent of egg laying in all areas will not be known until hatching begins.
Metarhizium was used to kill these locusts in Queensland.
Metarhizium will also be used in trials in Western Australia for the first time by the Agriculture Protection Board, the body responsible for locust control in the region.
Metarhizium has long shown promise as a biopesticide to control a range of insect pests.
Cullen says the metarhizium fungus used is a native strain that was originally collected from the spur-throated locust. Because the fungus is a non-chemical product, it reduces hazards to users and the environment and cannot cause residue problems.
"The strain is relatively specific to locusts and grasshoppers, and this has been confirmed in our field trials. Overseas data confirms that the fungus is safe and has no adverse environmental side-effects," says Cullen.