Australian plague locust update

Situation update – outlook for summer 2025

Australian plague locusts (Chortoicetes terminifera) are native insects that, if left unmanaged, can pose a serious threat to pastures, crops and horticulture.

There were few locust activity reports in Victoria during 2024. Limited sporadic breeding is possible under suitable habitat conditions, especially in the Mallee district where above average rainfall is expected, but any resulting population is likely to remain at low levels. There is a very low to low risk of a regional infestation developing.

Throughout November 2024 locust populations remained at low levels across inland eastern Australia with consistent low-density adults identified in western Queensland and southern New South Wales (NSW) and some localised medium-density populations of adults persistent in the central and western regions of NSW.

The overall outlook is for low-density populations across inland eastern Australia, with possible localised medium to high densities of summer generations developing in parts of NSW and Queensland.

There is a low probability of any significant migration or dispersal events likely to impact Victoria developing during summer and a low overall likelihood of the occurrence of widespread infestations.

A summary of locust activity throughout Australia is provided by the Australian Plague Locust Commission via the Locust Bulletin.

Where are locusts found?

Locusts naturally inhabit the far north-west of NSW and adjacent areas of Queensland and South Australia and the south-west region of Western Australia.

Intermittent locust populations may also be seen in varying concentrations from season to season around regional Victoria. In any given year, it is possible that locust swarms could migrate into Victoria from interstate.

Who is responsible for managing locusts?

In Victoria, government, public land managers, private landholders and the community all have a role to play in managing locust populations and minimising their impact.

Landholders are responsible for reporting and managing locusts on their land.

Agriculture Victoria continues to undertake surveillance and works closely with all stakeholders to provide relevant, timely and accurate information on locust populations and movements throughout the season.

Locust Management Strategies

Ground control using a chemical insecticide is the most successful method to manage locusts. The most effective time to spray locusts is at the second or third instar stage (around two weeks after hatching), when hoppers are wingless and band densities reach or exceed 80 hoppers per square metre. At this stage, hoppers form large, slow-moving bands, providing a clear target for efficient and effective insecticide use. Programs to treat adult flying locusts are generally ineffective.

For more information about various control options for the management of locusts, see Managing Australian plague locusts.

Further information:

Managing Australian plague locusts

Information for households and gardeners

Australian plague locust – biology and behaviour.

Visit Agriculture Victoria's Australian plague locust online learning module page for a twenty-minute interactive short learning course.