Grain growers seek support to control paddock pest: ‘Mice are becoming our biggest threat’

Pesky mice are chewing their way through farmers’ returns with the state’s grain producers blaming the rodents for reduced yields.

Lower Eyre Peninsula grower Peter Glover says mouse numbers can quickly explode on farm and it is necessary to react quickly if an issue emerges. Picture: Jack Davies

Pesky mice are chewing their way through farmers’ returns with more than three quarters of the state’s grain producers blaming the rodents for reduced yields.

In some areas the situation has become so bad farmers have labelled mice “our biggest threat” to the multibillion-dollar industry.

Farmers’ concerns about the paddock pest have been revealed in a survey by peak industry body, Grain Producers SA (GPSA).

Taken ahead of this year’s cropping program which is now underway, it found 78 per cent of grain producers had crop yields impacted by mice in the past two seasons.

Mouse damage last season in the Cowell, Cleve, Mangalo and Rudall areas was described as “devastating” while another farmer said “mice are becoming our biggest threat in our cropping system”.

GPSA chief executive officer Brad Perry said it was crucial farmers had access to effective control methods, including “double strength” mouse bait, when they needed it.

“While mice numbers are currently low to medium across the state, if we get rain and strong germination, mouse populations can increase fast … if there’s access to chemistry available that gives grain producers an advantage to stop mice in their tracks,” he said.

The nation’s worst mouse plague, in 1993, is estimated to have caused $96 million worth of damage to crops and livestock.

Mice have the potential to wreak havoc to the state's grain production. Pictures: Mouse Alert website

The CSIRO, which in a joint federal venture with the Grains Research and Development Corporation (GRDC) tracks mouse numbers through its Mouse Activity Report, warns “mouse numbers can rapidly escalate under the right conditions … farmers can have a costly and escalating problem.”

The April data shows “localised areas of moderate to high activity”, including in SA’s Adelaide Plains and across the Victorian Mallee and Wimmera regions.

Mr Perry said many farmers were frustrated they’d been blocked from accessing a double strength bait approved as an emergency response to a mouse plague several years ago which had been “extremely effective in combating mice on farm”, issued under a permit system.

He said Grain Producers Australia had failed in its bid for farmers to get access to it beyond last December.

“Grain producers normally bait around seeding time so as far as accessing the double strength bait during the 2024 seeding period, we’ve missed the boat,” he said.

An aerial shot of a canola crop with patches eaten out by mice. Picture supplied by Peter Glover

Peter Glover who farms about 9000 hectares at Yeelanna on the Lower Eyre Peninsula said mice were something growers constantly kept a watch for, due to the speed at which mouse numbers could build up.

“Most have a ‘one mouse policy’ … timing is critical, you’ve got to be onto (any issues),” the Westbrooke Ag partner said.

“Two years ago my brother, also a farmer, was flying over the property in his plane and noticed areas in the canola where significant damage had been caused by mice that we hadn’t realised were there – we went out the next day and baited.

“Traditionally, we don’t have as many issues here as you do when you get closer to Adelaide; there’s a grower I know of (in the Pinery area) who had to bait eight times and still his canola crop struggled to get established.”

Mr Glover said mice could dig up grain after it was planted and also eat germinating