North West Local Land Services Senior Biosecurity Officer John Busby said the size and number of swarms being detected now are a real concern going into the autumn crop planting season.

"The reproduction potential of these swarms puts pastures and autumn crops at risk," Mr Busby said.

"Monitoring what is happening on ground is key, so that coordinated control programs can be initiated when conditions are appropriate for managing their impacts. Knowing where these swarms are headed and if they are laying eggs is the first step to minimising the impact to Landholders."

Adult plague locusts usually like to lay eggs in harder loamy red soils, especially on compact roads next to crops, tree lines and farm buildings, especially those built on higher ground such as ridges.

Locust egg beds can be identified by a series of small holes in the earth, but they can be difficult to find. Monitoring these egg beds over the next few weeks will help to identify any hatching nymphs early.

Once hatched, the time for implementing control is at the third Instar or generally three weeks post hatching when they start to band together on the ground.

One reliable indicator of locusts hatchlings emerging is the presence of flocks of ibis, wood swallows, crows and other large birds, which like to feed on them.

"Landholders play a critical role in reporting sightings of plague locusts and to continually monitor the situation on their properties," Mr Busby said.

"It is highly important Landholders get started on control programs as early as possible to greatly reduce the overall population which could lead to increased activity and populations in the coming spring."

Landholders that suspect any indication of locusts hatching or flying near you, should report it immediately to their local Biosecurity Officer by calling 1300 795 299.

How to identify a plague locust:

Further information can be found on the NSW DPI website: https://www.dpi.nsw.gov.au/climate-and-emergencies/locusts