The red mite or chicken/poultry mite (Dermanyssus gallinae) is a common external parasite of poultry and wild birds and although very small it can be seen by the naked eye. Red mites feed on blood, feathers, skin or scales of birds and a large infestation level of mites will cause stress to the birds, leading to reduced egg production, anaemia and in extreme cases death. Red mites can be brought to your flock or chicken house by wild birds or mammals.
Red Mite and its Life Cycle
Red Mites are Arachnids and as such have 8 legs and belong to the order Acari. As with all mites they have an unsegmented body and in the adult stage, 4 pairs of legs and mouthparts which are adapted for piercing. The adult red mite measures approximately 1mm in length and 0.4mm in width, varying in colour from grey/ white to red depending on the level of blood engorgement.
Red mites feed on the bird between one and two hours each night, only in the dark, retreating during the day into cracks and crevices in the hen house, where they lay their eggs. This can make them hard to spot and treat before the infestation becomes large.
The female mite lays clusters of eggs near the chicken’s roosting area, the eggs of red mite are small (0.4mm x 0.25mm) oval and pearly white. Under warm conditions the eggs hatch in 2-3 days into 6-legged larvae. Before the first feed the larvae moult into an 8-legged protonymph (usually within 24 hours of hatching). These protonymphs start to feed on the roosting birds and moult to a deutonymph that continues to feed before moulting into an adult male or female.
Under favourable conditions a mite can complete a life cycle, from egg to a laying female in 7 days. So populations can build up extremely rapidly within poultry houses. To make matters worse the red mite can survive for up to 8 months in cracks and crevices without a blood meal.
Spotting the signs
If you are to avoid a major infestation of red mite it is important to be vigilant and treat the problem before it grows. One tell-tale sign of infestation may be the chickens reluctance to go back into the hen-house at night. The best time to check for red mites is early morning, when they can be seen easily by the naked eye after feeding on the blood of the birds overnight. Another tell-tale sign is a build up of a grey dust in the coop, this is the waste matter from the mite. Look particularly under perches and in perch sockets for live mites, they can also be found hiding in the dust on the floor under bedding and in the timber joints.
Red Mites versus Red Spider Mite
Red mites should not be confused with red spider mites or similar clover mites which are relatively harmless garden bugs. The red spider mites are a bright red colour and are seen during the day often on brickwork. Red mites are usually grey during the day and even when engorged with blood are not the bright red/ orange colour of the spider mite or clover mite.