Situation Overview

Egg-bearing locusts were recorded during Autumn 2008 throughout Victoria in the irrigation area surrounding Shepparton. It is expected that there will be a significant hatching of locusts over a large area (1.25 million hectares) in Spring. These locusts could severely damage pastures, cereal and horticulture crops in the area if no control programs are undertaken.

A locust plague in the irrigation areas of Victoria would be a further blow to properties already suffering the impact of the prolonged drought and the prospect of low water supplies next summer. If eggs are present, locusts are expected to start hatching in this area from early October in the far north west of Victoria and from mid-October in north central Victoria, through to late autumn. DPI will alert the community when hatching is likely to commence.

It is important to control locusts early in the season to minimise potential damage to crops and pastures. Locusts are easiest to control during their early stages as hoppers when they are unable to fly. Once they become adults, control measures become much more difficult and expensive.

Landholders will be able to control them at the early stage by using one of the several chemicals registered for use in the specific control of locusts.

DPI will implement an integrated control plan on public or private land, where the density of hoppers is high enough to pose a major threat of maturing into adults and moving to other areas.

If no control is undertaken in October and November and there is adequate green feed for developing adult locusts, a more significant and dispersed egg laying period in December – early January will occur.

The need for a second, more extensive hopper control program may occur in late January and February if conditions continue to be favourable.

DPI will lead and coordinate the Victorian Governments response to locust hatchings in Victoria. Further information about the current situation in Australia is available from the Australian Plague Locust Commission (external link).

Recent Incursions

The latest incursion into Victoria resulted from a major outbreak that was initiated in south west Queensland in Autumn 2004. Australian Plague Locusts arrived in Victoria in Autumn 2004, survived as eggs in the ground through winter 2004, maintained a relatively small population from December 2004 to April 2005, then exploded in numbers in Spring 2005.

The outbreak was concentrated in two areas, north central Victoria for up to 100km around Mitiamo, and in the Tambo Valley around Swifts Creek.

DPI and Landholders undertook extensive control during December 2005, and January and February 2006. A very few Australian Plague Locusts hatched in spring 2006 but, due to the dry conditions, did not survive.

Locust or Grasshopper

What is the difference between locusts and grasshoppers? – There are many species of each. Locusts form into bands as hoppers (flightless young) and swarms (adults). Grasshoppers do neither.

For more information on plague locusts see the Australian Plague Locust Commission (external link).