The red mite (Dermanyssus gallinae) is approximately 1mm long and is a brown/grey colour but becomes red after feeding on the blood of its host. Red mites do not live on the birds themselves but can usually be found in crevices and the roof of the hen house. At night the red mites come out to feed on the roosting birds and their nocturnal behaviour can make them hard to spot.
Signs of red mite infestation include anaemia which can be seen as pale combs and wattles, a drop in egg production, eggs with blood spots on the shell and general unthriftyness or distress. Upon close inspection of the hen house a whitish-grey powder can often be found in crevices or other hiding places. Red mite can live for up to 6 months without feeding so it's important when buying second hand hen houses or introducing new birds that the hen house is treated for red mite. There are numerous treatments on the market ranging from chemical based treatments to completely organic products, whichever product is used it is important to follow the instructions carefully and to ensure that every nook and cranny is thoroughly treated. In addition, don't forget about the poultry run, this can often be a favourite hiding place for red mite too. Remember that whatever product is used it is only the adult red mite that will be killed therefore it is essential to repeat the treatment about a week later to kill any recently hatched eggs. Although red mite are virtually impossible to eradicate completely you can help to prevent them from becoming a threat to your birds by being vigilant and treating the problem promptly.
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