Full Breakdown
Mouse Plague Threatens Grain Farmers in Western Australia and South Australia
4/22/2026, 9:21:46 PM
Current Situation and Impact on Farmers
Grain farmers in Western Australia (WA) and South Australia (SA) are facing a significant mouse plague, with alarming reports indicating mouse populations reaching plague levels. Steve Henry, a researcher at the Commonwealth Scientific and Industrial Research Organisation (CSIRO), noted that a plague is defined as more than 800 mice per hectare, and current reports from WA indicate numbers as high as 3,000 to 4,000 burrows per hectare. The areas around Geraldton, approximately 400 kilometers north of Perth, are particularly affected, with similar concerns emerging from the southern WA wheatbelt and the Adelaide Plains in SA.
The implications of this mouse surge are severe. The previous mouse plague in eastern Australia during 2020-21 resulted in an estimated $1 billion in damages, affecting not only crops but also livestock health due to contamination from mouse urine and carcasses. The current situation poses a risk of similar economic and social repercussions, especially as farmers prepare for the critical seeding period.
Factors Contributing to the Plague
The recent increase in mouse populations is attributed to a combination of environmental factors. Following two years of drought, record-breaking rainfall has created favorable breeding conditions for mice. Henry explained that the breeding cycle of female mice, which can produce six to ten offspring every 19 to 21 days, exacerbates the problem. Farmers have reported seeing mouse activity increase significantly over the past month, with some indicating it is the worst they have seen in years.
Official Responses and Recommendations
In light of the escalating situation, the agriculture minister, Julie Collins, acknowledged the challenges farmers are facing, including rising costs due to the ongoing conflict in Iran affecting fuel and fertilizer supplies. Farmers are calling for access to higher doses of zinc phosphide (ZP) mouse baits, as current options are deemed insufficient for effective control. Mark Fowler, president of the WA Farmers grains section, emphasized the urgency of the situation, particularly as seeding is already underway.
The CSIRO has recommended that farmers monitor mouse activity closely and consider applying baits during seeding in areas with high mouse activity. This proactive approach is crucial, as once the seeds are consumed, the opportunity to replant is lost, particularly for high-value crops like canola.
Criticism and Concerns
Despite the recommendations, there are concerns about the adequacy of current baiting options. Andrew Weidemann from Grain Producers Australia highlighted the need for stronger bait formulations to ensure effective control in the paddocks. Agronomists like Nathaniel Lloyd have noted an increase in demand for mouse control products, indicating that the issue is becoming a priority for farmers as they prepare for the seeding season.
Verbatim Quotes
- “We’re getting reports out of Western Australia of 3,000 or 4,000 burrows per hectare.” — Steve Henry, CSIRO Researcher
- “We have an urgent problem that exists right now.” — Mark Fowler, WA Farmers
- “So, if you lose a whole heap of your canola crop, you probably won't have the option to re-sow it.” — Matt Davey, Farmer
Conclusion
The mouse plague in Western Australia and South Australia presents a multifaceted challenge for grain farmers, compounded by environmental factors and rising operational costs. As the situation develops, farmers and agricultural authorities are urged to implement effective control measures to mitigate the potential economic and social impacts of this pest outbreak.
