Growers urged to monitor for mice after reports of extensive crop damage in Merredin

Merredin farmers have been finding “ute-sized” mouse holes in their crops, with growers across the grain belt being urged to monitor for signs of the destructive pest.

Reports of significant mouse damage have prompted a warning from the Grains Research and Development Corporation, which is calling on growers to inspect their winter crops and be prepared to bait when required.

WA growers were heavily affected by mouse damage last year, with increased activity also expected this year because of the volume of grain left behind in paddocks after a record harvest.

Leading mouse expert and CSIRO research officer Steve Henry said mouse numbers could build rapidly under the right conditions, leading to crop damage throughout the growing season.

And with the Bureau of Meteorology predicting warmer, drier conditions this month — ideal for mice to breed — he said a perfect storm was brewing.

“Mice can do damage at all phases of the crop, so if they’re taking whole plants out when the crop’s being sown, there is a related loss of yield when the crop is harvested,” Mr Henry said.

“The key message now is to be vigilant in the late winter and early spring, and be prepared to bait if you see signs of mouse activity.”

In late June, GRDC representatives spoke with growers in Merredin and surrounding areas who reported crop holes “the size of utes” caused by mice.

Some growers had not actively monitored their crops before or during seeding, the GRDC said, and were unaware of the level of risk from mouse activity.

The feedback came at a June 27 field walk arranged by the GRDC, Merredin and Districts Farm Improvement Group, and Nutrien Ag Solutions Merredin.

“Early detection and integrated management across the farm is crucial for reducing the risk of mouse impacts,” the GRDC said in a statement.

“Once mouse numbers are very high, it is very difficult to reduce damage and control strategies can be costly.”

GRDC has invested in additional surveillance and extension activities to alert growers of mouse outbreaks across the state throughout the 2022 season.

May 2022 data showed mouse activity hotspots across all five port zones, with particularly high levels around Coorow, Northam, Jerramungup and Beaumont.