Predatory Flies (slurry flies)

Predatory flies - in Latin hydrotaea aenescens​ (also known as bio flies, slurry flies or manure flies) are natural enemies of house flies (Musca domestica) and ​biting house flies - also called stable flies (Stomoxys calcitrans). They are often found in many pig and cattle stables.

Predatory flies fight unwanted flies in pig and cattle stables

Predatory flies can be used to fight other flies in stables, because their larvae are so-called predatory larvae that feed on eating the larvae of other flies. Miljøfluen® specializes in raising Predatory flies in such quantities that farmers can benefit from the animals' characteristics and therefore obtain an effective but also environmentally friendly weapon against unwanted flies in the stables.

Predatory flies are well suited for stables with slurry ducts

The predatory fly's work proces is suitable for combating other flies in stables with slurry ducts, as it favors moist areas in the stable to breed and seek food. When its larvae come into the world, they begin to eat the larvae of the house fly and the sting fly, which are also found in the slurry ducts. In this way, the unwanted larvae are exterminated before they can develop into adult flies.

​ If you have deep bedding in the stable, we recommend that you use mini wasps.

A small and calm, predatory fly

Predatory flies live in the wild in Denmark and the rest of Europe, but act differently to the house fly, as they do not swarm, are calm and look towards dark and humid areas in the stable. Nor does it sting the animals as biting house flies do and bother therefore neither humans nor animals in the stable.

With biological control of flies you avoid resistance

Unlike using chemicals (biocides) to fight unwanted flies in stable areas, resistance can never occur using the manure flies. This can sometimes happen with the use of chemical and you may have to change mark of chemical if you experience that the effect of the poison disappears. This is avoided when using Predatory flies or mini wasps.

​ Miljøfluen® helps you, for free, to plan for the best solution for your stables.

Contact us

Contact us on phone: +45 98 25 99 00.​ or by email:

​About Miljøfluen

About Miljøfluen

In 1993, Miljøfluen® established production of predatory flies and mini wasps to control stable flies in Danish farms. 

Predatory flies and mini wasps are naturally existing in Danish and most of European nature and by means of the way they act and live, they reduce the annoying stable flies.​



VAT No.: 32818129

​Kildalgårdsvej 3,
​DK-9330 Dronninglund

​Phone: +45 98 25 99 00


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