There is a variety of beetles and mites that are a common inhabitant of birds and birds' nests, but do not become apparent until the nest is no longer in use and the insects have to travel to find food. When this happens, they are usually to be found in the upper rooms of houses.

Some beetles are inhabitants of the nest and its surrounding areas and live off the feathers and nesting materials. Mites are parasitic on the birds themselves but are left in the nest site on feathers.

The most common invaders of your home are black fur beetles, varied carpet beetles, spider beetles and the poultry mite.

The black fur beetle is about a quarter inch long and black or very dark brown in colour, and has two very distinctive white spots on the wing cases.

The varied carpet beetle is smaller, rounder and has a patterned back usually of yellow, white and brown patches.

Spider beetles, as the name implies, look like small spiders and are either gold or brown in colour.

The mites are very small and vary in colour from light brown to dark red and are usually found in large numbers.

If an infestation is found or suspected, a check should be made of gutters, barge boards and roof spaces, and any birds' nests and dead birds removed. Any carpets, clothing, etc., stored in the roof space could act as a reservoir of infestation and should be removed.

The life cycle of the beetles can be quite lengthy (sometimes more than 12 months) dependent upon the temperature conditions. The larvae usually hibernate over the winter period.

In roof spaces, the use of greenhouse insecticide smokes can be effective if the conditions are such they can be used with safety. Smokes should always be places on a large tin lid or old saucer, away from combustible material. If more than one smoke is to be used, the furthest from the access should be ignited first,

Do not breathe the smoke. Always follow the manufacturers instructions.

Space spraying in the areas should only be carried out by specialists.

Where roof spaces are to be treated, it must be ascertained beforehand if the roof space is in use by bats, as it is now an offence to destroy a roost and many insecticides are harmful to bats (Wildlife and Countryside Act 1981).