Carpet Beetles can be a real nuisance in the home and cause great destruction by chewing holes in various household items such as carpet, furniture, bedding, manchester, clothing and accessories. In some people, contact with the fine hairs from cast skins (moults), or, from living and dead beetles and larvae, can cause an allergic or skin reactions such as dermatitis. Given the unnecessary destruction of property and the potential health risks associated with Carpet Beetles, it’s important to prevent and control infestations in the home.
There various introduced and native Carpet Beetle species, both of which have the potential to cause issues in the home.
Adults are beetles while the larvae are grub-like.
Adults are generally 4 mm long and are a compact oval shape. Some species, such as the more common introduced European Carpet Beetle (Anthrenus verbasci) have a mottled banding pattern of pale-brown or yellow, brown and white scales, while other species are plainer and blacker.
At the front of the small head are two compound eyes and a short pair of club-like outward facing antennae. On the underside of the head are chewing mouthparts.
Behind the head is the first segment (pronotum) of the middle section of the body (thorax). In beetles, this segment is quite pronounced and is a round-shaped plate with a point directed towards the rear. Behind the pronotum, attached to the upper side of the body, are two pairs of wings. While at rest, the hardened front pair provides protection to the semi-transparent flying pair. On the underside and middle section of the body are three pairs of thin outward facing legs.
Larvae are up to 5 mm long, are light brown to yellow in colour and have a large head which tapers to a smaller rear (abdomen). Larvae have a distinct head capsule with chewing mouthparts and three pairs of legs towards the front and underside of the body. Larvae are covered in thick bristle-like hairs, often in transverse bands along the body, with dense tufts at the tip of their abdomen.
When disturbed, beetles fold and hide their legs close to their body, while larvae erect their bristle-like hairs in defence. Adults are attracted to light, while larvae prefer dark and sheltered places.
After mating, females fly to a suitable laying site where future larvae can feed on a food source. Females lay up to 40 sticky eggs which are laid individually at various locations. Eggs are less than 1 mm in length, oval-shaped and cream-coloured. Eggs generally hatch within 10 to 20 days.
Larvae are grub-like and shed skin (moult) at each stage of growth development. During cold periods, larvae can hibernate until warmer weather returns. In spring, larvae find a sheltered and dark place to pupate, often burrowing into their food source. Larvae pupate in their final skin and emerge after 10 to 30 days as the adult beetle form. Depending on the species, larvae can live from 1 to 3 years, while adults generally live and die within 2 to 6 weeks.
Adult Carpet beetles are predominantly found outdoors and feed on the pollen and nectar of flowers during the day. During breeding season, females sometimes venture indoors to lay eggs.
Depending on where Carpet Beetle eggs are laid, larvae can be found either indoors or outdoors and are most active during the night.
Larvae can be found indoors feeding on natural fibres including animal fibres such as silk, leather, feathers, wool and hair; and plant fibres such as cotton and other foodstuffs. Larvae also feed on the skin and hair of dead animals and insects; and spiders’ webs.
Larvae are often found in crevices, junctions and seams of household fabric items such as:
Larvae can be found outdoors in:
Birds, mammals, lizards, frogs, ants, spiders and parasitoid wasp larvae feed on Carpet Beetle larvae.
Spray Blitzem! Insect Killer Concentrate onto infested carpets, floor areas, in cupboards and wardrobes and around furniture, bookshelves and skirting boards. Do not apply to clothing or bed linen.
To reduce the potential for dermatitis reactions to the cast skins, or from living and dead beetles and larvae, wear gloves and use a dust pan and broom to pick up mess. Ensure areas are well vacuumed and wipe hard surfaces with a moist paper towel, then discard into the rubbish bin.
Wash any garments and linen suspected to be infested with eggs in the washing machine in hot water and then place into the dryer for at least 30 minutes.
Carpet Beetle larvae damage can cause holes in carpet and other fabric household items. However, damage can be confused with that of Silverfish and Clothes Moths.
Further evidence of Carpet Beetles in the home:
Prevent Carpet Beetles from entering the home:
Remove potential food sources:
Monitor and control quickly: