PADDOCK REPORTING FOR GROWERS TO SHARPEN THE NATIONAL MOUSE ACTIVITY PICTURE

Growers experiencing significant mouse pressure can now submit paddock-level evidence to have their agroecological zone’s (AEZ) mouse activity rating reviewed as part of the process that determines access to ZP50 mouse bait.

The rapid in-paddock assessment pathway will ensure evolving mouse activity is found quickly and if moderate or above levels are confirmed, ZP50 use will be permitted under the emergency permit held by Grain Producers Australia.

Development of this reporting method has been led by the Grains Research and Development Corporation (GRDC) and is in direct response to feedback from growers and advisers.

GPA Western Region Director Duncan Young said the AEZ monitoring network was a key factor in the national permit being approved and this evolution complemented the network by ensuring growers can respond as conditions change.

“The network is working well and provides a nationally consistent way to track mouse activity and direct ZP50 to areas where the evidence shows it is needed,” Mr Young said.

“With GRDC developing this reporting pathway we're recognising that the knowledge growers and advisers have from walking paddocks and monitoring local conditions needs to be considered.

“If growers in a low-rated zone are recording mouse pressure that may justify a moderate or high rating, they now have a clear process to put that evidence forward and have it reviewed.”

Three Western Australian zones - WA Northern, WA Central and WA Sandplain - are currently rated high and ratings are updated fortnightly.

Mouse activity is also building in parts of Queensland and northern New South Wales.

The timing is critical in WA, where canola is flowering across parts of the grainbelt and other winter crops are advancing towards reproductive stages and grain fill.

“Mouse activity can change quickly and can be highly localised,” Mr Young said.

“In flowering canola, mice can damage flowers, pods and developing seed, and the potential for losses increases as crops mature.

“Growers should continue walking paddocks, checking for active burrows and crop damage, and recording what they find.”

ZP50 was first made available under an emergency permit during the 2021 mouse plague, following CSIRO research that demonstrated more reliable control than the standard ZP25 formulation.

GPA secured the current emergency permit in response to renewed mouse pressure in 2026.

Its agile design links access to activity ratings from the national monitoring network, which are updated fortnightly as conditions change.

“The brilliance of this permit is that access can move with the evidence rather than being fixed to particular locations for the life of the permit,” Mr Young said.

“That allows industry to respond to changing mouse pressure while maintaining the stewardship, safety and reporting requirements needed for a higher-strength product.

“We also recognise this is new territory for growers, industry and the regulator.

Listening to growers and ensuring credible paddock evidence can be considered is an important part of making this approach work.”

Submitting a rapid assessment does not automatically change a zone’s rating or provide access to ZP50.

The evidence will be assessed through the national monitoring process, and ZP50 can only be used if the zone is formally rated moderate or high.

Growers must also complete GPA’s stewardship training and comply with all permit conditions, including record-keeping and reporting requirements.

Access the rapid assessment pathway at: GRDC Mouse Rapid Assessment – Low Zone

Check current ratings using the GRDC AEZ Postcode Lookup Table and Map.

Permit, training and reporting information is available at GPA Mouse Control.

ENDS

Further information:

GPA Executive Officer Rachael Oxborrow: 0416 705 193

GPA Western Region Director Duncan Young: 0448 822 666