7 tips to protect grain stores from rodents

Rodent numbers are rising this winter – and could ruin grain stores. But an integrated pest management approach and variety of baits can help prevent infestations from resulting in grain losses and contamination.

Rats can thrive in a grain store and multiply quickly, with one breeding pair escalating to 1,250 in a single year. It better and less costly to prevent an infestation in the first place than try to eliminate rodents after they gain a foothold on the farm.

Rodenticides are an effective way of controlling an infestation but should be carefully monitored. A clean and tidy farm will reduce the risk of infestations – and farmers should select bait carefully.

With new legislation that prevents the use of rodenticides containing bromadiolone and difenacoum in open areas coming into effect on 4 July 2024, grain store managers should consider baits containing actives such as cholecalciferol or brodifacoum.

Over the years, I have come up with seven tips to prevent rodent infestations, which are outlined opposite.

David Reece is a pest control specialist for bait supplier Lodi UK

1 Make a plan and regularly walk the farm looking for burrows and record where rodent activity is apparent. Understanding areas that rodents are using to access food and water can help make trapping or baiting much more effective.

2 Just because there are signs of rodents it doesn’t mean that baiting the area will always be totally effective. Regular checks and non-chemical measures such as rodent proofing buildings and other areas can also pay dividends.

3 Rats do not like open spaces. Reduce their activity by keeping the farm tidy and clear of rubbish. Prevent access to food and water by securely storing feed and repairing dripping taps. This will reduce the likelihood of rats seeking harbourage and breeding.

4 Rat-proof buildings by ensuring there are no access points for rodents, This will reduce the risk of infestation. Small measures like using mesh smaller than 10mm to cover gaps in grain stores will help to prevent both mice and rats gaining access.

5 Rats have a fear of new objects (neophobia). Establishing bait boxes at least four weeks ahead of baiting will reduce neophobic behaviour and improve bait take. Placing boxes ahead of time and even adding non-toxic bait can help the boxes become trusted.

6 When non-chemical methods have been exhausted, rodenticides should be used methodically and carefully.The fastest acting cholecalciferol bait is Harmonixl. It can control an infestation in seven days. It is not an anticoagulant so it can be used inside and out. It also poses less threat to non-target species such as birds and other wildlife.

7 Using a highly palatable bait is a particularly important consideration in grain stores where food is plentiful. Harmonix or Lodi Gems Sapphire both have a highly palatable wheat-based formulation so they are are more appealing to rodents