Field mice are threatening agriculture

Agriculturists and farmers in the European Union and German-speaking countries are on their highest alert for possible field mouse invasions. Total crop losses are not rare, especially when more than 2000 rodents or even field mice are spread out over each hectare. Agriculturists can live with mice but some years there are too many and a very serious mass infestation with large amounts of damage would be very dangerous.

Additionally, there have not been any approved and effective active ingredients for agriculture in the EU since 2017. The European Union and Commission is on the hunt for new, effective, non-chemical active ingredients for use as agricultural rodenticides as agriculturists have no interest in using prohibited active ingredients to protect their crops and cultivated areas whilst nonetheless making themselves liable to prosecution. In biological and bioorganic agriculture the situation is no better, rather it is more complicated. The problem of field mice, mice and rats in agriculture repeatedly reaches orders of magnitude and damages which are not initially anticipated as mice can multiply very quickly in a short amount of time.

In the past few years massive mouse infestations have been identified and the situation is now becoming much more wide-spread.  In extreme situations, special permission for the use of chemical active ingredients, so-called rodenticides like bromadiolone, are granted in agriculture but we cannot rely on this and it is therefore not an alternative. Although animals multiply explosively, the current licensing situation prohibits action against damaging plagues of mice. Agriculturists are protesting but without success, and bromadiolone and other chemical rodenticides will probably have to be reached for once again. Mouse bait may only be placed in a bait box or directly into mouse holes, depending on the EU country. Everything is strongly regulated by law, and this practice can be very time-consuming and cost-intensive depending on the cultivated area.

Agriculturists are also trying to use perches for birds of prey or cats in the cultivated area as well as diversionary food at the edge of the field. Wheat, roasted barley, nut-praline cream and honey are recommended as food. Mice enjoy a friendly image amongst the general public, children watch popular cartoons featuring mice, there is the comic figure of Mickey Mouse, the field mouse is harmless and loveable in fantasy literature, and town mice are allowed to run riot in people’s larders. But field mice are a menace for agriculturists and a danger to their basic income, as well as also causing large amounts of damage to plants, trees and cultivated areas.

The threat from mice, and more specifically field mice and common vole, can be seen in the mouse holes in agricultural fields. Severely affected areas are even visible from aeroplanes. Mice and rats live on the end product such as vegetables, fruit and grains, and eat roots and subterranean plant parts in equal measure until the plants and trees have been completely destroyed. In 2007, damages of € 100 to 300 million arose in agricultural areas in Germany alone, not including the damages to the rest of the production chain. Additionally, mice and rats can pass on dangerous bacteria and viruses which makes field mice, primarily, amongst the most damaging pests to agriculture. The type of soil cultivation desired by politics and society promotes an increase in rodents.

EU politicians are searching for effective active ingredients for agriculture to eliminate the problem but they have been doing this for many years now with no results. The situation has actually worsened as there have not been any licensed active ingredients for controlling mice in agriculture since 2017. This is not a solution, rather a poor commitment and very thought-provoking politics as interesting active ingredients exist and a license for them just has to be pushed forward. Efficient pest control measures are in short supply and mice have therefore multiplied significantly in good years. Mice in agriculture land in Germany can cause damage up to € 400 million yearly. 

It is already known that the population evolves in a wavelike fashion with a lesser infestation every 2-3 years following a major infestation. There are always fields and cultivated areas with lots of field mice, no agricultural area is spared. Cornstalks which have been bitten off are seen in fields of grain and the entire rootstock of fruit trees around the holes and burrows has been gnawed at and eaten away.  The damages per agricultural business average between € 1000 - 5000 per year and can be considerably higher depending on the size of the business.

A mild and dry winter provides the mice and rats with the opportunity to multiply significantly. It should be remembered that mice are already sexually mature 2 weeks after birth and produce their first offspring after 4 - 5 weeks. It is easy to comprehend how reproduction can explode and this is why regular, effective control measures must be carried out. The plough is also commonly used in agriculture to destroy passageways and burrows. Checks should be regularly carried out for new, fresh holes in order to place potentially poisonous bait, mouse poison or rat poison there or nearby. As soon as the mice have amassed their winter stocks in their holes and burrows, mouse bait is usually no longer attractive.

A mouse poison or rat poison which is designed to be very attractive to mice and rats as well as working very effectively would be the best solution to combat the problem simply, quickly, efficiently and cost-effectively.  There are no effective, already licensed active ingredients in the EU for biological or bioorganic agriculture which is why the natural active ingredient GTX is very interesting. It will be the best and most efficient solution for pest control against rodents in the form of mouse poison, rat poison and rodenticide in biological and conventional agriculture that has ever existed on the market once it is licensed - a true champion of effectiveness.

Special permits depending on the EU country mean that mouse bait cannot be simply strewn around but can only be placed in bait boxes, even though placing it directly into the fresh holes would prove more effective. As a precautionary measure, it is recommended to regularly mulch field edges so that fewer mice encroach on the farmed cultivated areas. Perches for birds of prey are also deployed, even though birds of prey like the common buzzard mainly hunt ill and old mice. Placing cats directly in agricultural plantations is perhaps an alternative, depending on the scale of the problem.  Agriculturalists and farmers can only partially limit the damage at the moment because there are no really effective measures.

Banned chemical active ingredients are no longer reliably effective due to rodents developing resistance. However, there will always be mouse infestations, which is why it is time for agriculturalists to discover and use new methods and solutions and for politicians to campaign for effective active ingredients with little or no risk to the environment which can be used in bio organic and conventional agriculture to be speedily licensed.