Museum Beetles

Key Features

Adult Museum Beetles (Anthrenus museorum) are small (2 - 3 mm) insects shaped rather like ladybirds. Adult museum beetles are normally speckled in appearance, fly readily, and feed on pollen and nectar. They cause no damage.

The larvae of the museum beetles, sometimes called 'woolly bears' feed on animal fibres such as wool, feathers and fur.

Biology:

As the larvae develop, through 5 moults, they cast off their skins, which may be the first symptoms of the infestation. The larvae hibernate through the winter, and usually pupate in the spring.

When pupation is complete, the adult museum beetle emerges and feeds on nectar and pollen only. When it has mated, the female museum beetle seeks out birds nests, fabric, carpet or accumulated fluff (inside buildings) on which to lay its eggs.

Distribution

Museum Beetles are most commonly seen in April, May and June, seeking suitable egg laying sites. They are often first seen on window-sills. Woolly Bears are most commonly found in October and November.

Significance

Extremely common, possibly of greater commercial importance than the clothes moth. Consumes animal (keratin) fibres eg. Fur, feathers, woollens, fabric, museum specimens. The larval stage only causes damage. Often associated with birds nests. Often found in domestic environments where they can cause damage to animal fibres.

Control:

A thorough inspection is necessary to determine the source and extent of any museum beetle infestation. The inspection must extend to every room in the premises and in particular the loft, where birds' nests may act as reservoirs of infestation.