2025 will go down as one hell of a year for natural disasters with cyclones and the floods that have encompassed much of the state for the first quarter of the year.
But for grain producers right across Queensland, a potential disaster of another kind is unfolding right before our eyes.
Mice, and lots of them. Breeding quietly in the fields that grow our food. Waiting to eat and destroy our crops, either as we plant them or as they mature and form grain.
Either way, this problem could be combatted and avoided so much more effectively, if we were able to use the product that we know will do the job – however our regulators seem powerless or reluctant to make the decisions needed in a timely fashion.
Landholders on the Darling Downs and Western Downs tell us that mouse activity is being observed in late summer crops and fallows about to be sown to winter crops. The numbers are increasing right across the Darling Downs more broadly, starting to impact many previously unaffected areas.
This is of particular concern given the timing, as the winter cropping season has just begun. Wheat barley and chick peas are being planted in the cropping regions of the state right now.
The damage the mice cause is significant, effectively destroying hundreds of thousands of dollars of crops and farm machinery.
Australia’s chemical controller APVMA is the regulator body for agricultural and veterinary chemical products.
But it seems powerless to prescribe the strength of treatment that is needed to stop this mouse plague from causing further damage.
Currently we only have ZP25 strength bait available. The CSIRO have proven time and time again that the ZP25 bait results in sub-lethal doses – meaning mice have to find multiple grains of bait to get a lethal dose.
Previous emergency permits allowed access to the ZP50 bait which is double the strength, meaning that each grain of bait has a lethal dose for a mouse – making the ZP50 bait consistently more effective than ZP25.
So why do they persist in insisting we use the less effective version?
Even worse, those mice that eat the toxin and don’t die because of the sub-lethal dose, actually become bait averse. Making this battle even harder.
It is critical that baiting takes place when background food is at it’s lowest level, that is, at sowing or post grazing.
It is critical producers have access to and are allowed to use the 50g mixing rate to give mice the best chance of encountering a lethal dose.
Given what we know, and how this has been proven time and time again by the CSIRO Rodent Research Team with support for the GRDC, we ask why does APVMA not allow access to the ZP50?
We originally had an emergency use permit for ZP50 (PER90799), but that expired in December 2023.
The APVMA have said they will consider re-issuing that permit if the situation once again becomes an “emergency”, which actually means they end up waiting for plague conditions before doing anything. Not ideal when this could be effectively prevented before getting to that state.
It is ridiculous to think that we have to wait until we are in such a dire situation that the grains and cropping industry is begging for help before the regulator will register the product.
Recent history shows the economic, social and mental health impacts of the mouse plague in NSW a few years back, was close to $660 million in losses. The mental health implications were also immense. Let’s not forget the social and economic impacts of a mouse plague either, invading your machinery, cars and houses.
The experience of growers on the ground has lined up with the CSIRO research – that the level of control needed to reduce the economic impact of mice in these enormous numbers and prevent further breeding is increasing to critical levels.
CSIRO reports that anything over 200 mice per hectare has a significant economic impact and considers a mouse plague to be 800-1000 mice per hectare. In some places in the Darling Downs and Roma districts we are walking on a knife’s edge – we are that close to being at plague proportions.
But if we were given the tools we need to control them we could reduce those numbers and take the pressure off.
Baiting can cost up to $30 per hectare when applied with an aircraft, and getting suboptimal results or no result at all is essentially a waste of time and money. In some cases bait is being applied twice, and still not getting the desired result. Throwing good money after bad.
Baiting needs to be done when there is little or no other food in the system, giving the bait the best chance of being picked up by the mice. Which is why it is imperative that the every grain of bait being used is the lethal dose for a mouse.
We urge all producers to log any and all mice activity on the mouse alert webpage as this helps us advocate for the emergency use permits we so desperately need.
If the CSIRO as the scientific authority says this strength of bait is needed, then that advice should be highly regarded by APVMA.
AgForce is a strong supporter of the role of APVMA as Australia’s robust, independent, science and risk based chemical regulator. But we often feel the narrow lens in which agvet chemicals are reviewed is counter-productive to industry.
APVMA often review chemistry or deny chemistry based on research from other countries, which are based on farming conditions that are not the same as in Australia. We have a very well resourced and funded GRDC that has funded a lot of research in this space already.
The APVMA has all of the CSIRO research that is the subject of four scientific publications. Everyone else can see the black and white data so why can’t the APVMA see the same logic? We hope to advocate strongly on this in coming weeks before this situation becomes completely out of hand and exponentially harder to control.
We urge the APVMA to make this a priority not only for Queensland but for all of Australia’s grain production districts. The economic cost we face is enormous, and increasing along with the burgeoning numbers of mice devastating our primary production.
