Carpet beetles are small beetles, usually around 3mm long, though their size can vary from about 1.5mm to 3.5mm depending on the exact species. As their name suggests, they are pests best known for damaging carpets and fibers such as clothing or furniture upholstery. The adult carpet beetle typically feeds on pollen from flowers, but the larvae are known for feeding on just about any type of animal fiber, such as wool, leather, silk, furs and feathers. They are quite common in gardens during summer months, which makes them almost impossible to completely eradicate.
How to Identify Carpet Beetles
There are many different species of carpet beetles, but the adults all share common qualities that make them fairly easy to identify. An adult carpet beetle is usually about 3mm long and have an oval shaped body. The most common species is the black carpet beetle, which, as you might think, is a shiny black bug. Other common species are more brightly colored, with some varying patterns of white, yellow, brown and orange. These include the varied carpet beetle and the furniture carpet beetle. They all have six legs and two small antennae on their head. Although they usually feed on flowers, they are commonly spotted in homes around lights and windows. This could indicate a larval infestation somewhere in the home.
The larvae, which cause the vast majority of problems, are actually larger, at about 6mm in length. They are covered with dense hairs or bristles, and have an alternating pattern of light and dark brown stripes. While they usually feed on organic animal materials, they may also attack synthetic materials such as polyester if they are heavily soiled with any type of food stains or body oils, but this is very rare. They prefer to feed in areas that are normally dark and where they won’t be disturbed. They may be found in closets, boxes where clothing is stored, or even in air ducts where they can find lint and pet hairs.
Life Cycle of the Carpet Beetle
Carpet beetle larvae hatch from eggs in the spring and early summer. They are most often found in birds’ nests where they can get a good start feeding on fallen feathers. In homes, eggs might also be left in areas where fabrics or clothing are stored. Depending on environmental factors, the larvae will mature to adults in anywhere from one to three years.
During the larval stage of their lives, they feed on the keratin and chitin available in natural fibers. Their sources of food will include dead insects, various animal hairs and furs, and feathers. Eventually they will enter a dormant period before they transform into adults. Again, the length of the dormancy can vary, but the main awakening factor seems to be the photoperiod, or length of daylight hours.
Adults will emerge between late May and early August. Now able to fly, they will make their way to flowering plants where they feed on the pollen and nectar. At this point, the life expectancy of the beetle is only about two weeks. Mating occurs during these final weeks, and eggs are laid in areas where it will be easy for the new larvae to find their first food. In the spring, the eggs will begin to hatch and the the cycle will start over with a new generation.
Signs of Carpet Beetle Infestation
Carpet beetle larvae can quickly move from one area to another as they search for food. Since they prefer dark and undisturbed areas, it can sometimes be tricky to find the main source of problems. First signs of an infestation will be damage to fabrics somewhere in the home. You may notice damage to clothes that have been stored, or have been hanging in the closet for quite a while. Other areas where evidence can be found will be along the edges of wall to wall carpet and on the underside or bottom edges of upholstered furniture. In addition to material damage, you might find the shed skin of the larvae in areas where they’ve been feeding, or even the larvae themselves.
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