New research published today in the Journal of Applied Ecology says the dung beetles and soil bacteria found in hedgerows, ponds and other natural habitats play an important role in naturally suppressing e.coli and other harmful pathogens before spreading to humans.

Matthew Jones, who led the research as part of his PhD project at Washington State University, said “Wildlife and livestock are often seen as something that endanger food safety, but our research shows that reducing on-farm biodiversity might be totally counterproductive”.

“Nature has a ‘clean-up crew’ of dung beetles and bacteria that quickly remove faeces and the pathogens within them, it appears. So, it might be better to encourage these beneficial insects and microbes”, he says.

Dung beetles bury faeces below ground and make it difficult for pathogens to survive. The research project showed that organic farms seemed to attract a diverse range of the dung beetle species that were most effective at keeping foodborne pathogens at bay.

“We found that organic farms generally fostered dung beetle species that removed the faeces more rapidly than was seen on conventional farms”, said Professor William Snyder of Washington State University.

The research also showed that organic farming encouraged higher biodiversity among soil bacteria, which decreased the survival of pathogens.

“Bacteria are known to poison and otherwise fight among themselves and the same may be happening here”, said Professor Snyder.

The results suggest dung beetles and soil bacteria may improve the natural suppression of human pathogens on farms, making a case for reduced insecticide use and the promotion of greater plant and insect diversity.

The full study was published today and is available here