Dermestid beetle - Common pests

There are four species of common household pest in the genus Dermestes, including the hide and larder beetle. All four species are similar in shape and are generally dark brown and 6-12mm in length.

Facts about dermestid beetles

Dermestid beetles lay eggs 2mm in length, in crevices of rooms where dry animal or food matter may be found. The eggs normally hatch within two weeks at a temperature of approximately 17 degrees C; this period will be reduced to 3 or 4 days at a higher temperature of up to 25 degrees C. When the larvae emerge they appear brown and yellow striped with bristle-like hairs and feed on dead animal or food matter nearby. The larvae will eventually wander away from the food source to a pupation site where it will burrow a short tunnel into a suitable material such as wood. After a week or two the adult beetle emerges and will live for approximately three months during which time it may hibernate to avoid cold spells.

How do they affect me?

Dermestid or House beetles are often found in domestic and industrial properties where they feed exclusively on dead matter. They are commonly found in domestic kitchens or in dining rooms where they feed on scraps of food, which have accumulated in the corners, or crevices of the room. They may also be found in roof spaces , under floorboards or in disused chimney spaces where dead mice or birds may lay.

How do you control them?

The first step in Dermestid beetle control is to trace the source of the infestation. This may be an old nest, animal remains, wood based lagging, soundproofing, wool based furnishing or the debris that accumulated between and around floorboards. Routine surveillance and regular cleaning are important. Small infestations can be dealt with using a general purpose crawling insect spray or powder, available from chemists, hardware stores or garden centres. Where infestations are extensive a thorough residual insecticide treatment is required. In such cases it is advisable to have a professional treatment carried out.