Australian Carpet Beetles

Introduction

Australian Carpet Beetles are native member of a small but significant group of beetles (family Dermestidae) that frequently invade homes and whose larvae feed on carpets and similar fabrics. It is the larvae of the beetle that are a common household pest

The larvae are bigger than the adults. Larvae hatch from eggs in the spring and early summer. Once hatched and until they pupate into adults, the larvae hide in dark, undisturbed areas and feed on organic material. Warmer temperatures will shorten the incubation and pupation times. Finding beetles on window sills in houses may indicate an infestation.

Habitat

Australian Carpet Beetles live in urban areas, forests and woodlands.

Distribution

Australian Carpet Beetles are found throughout Australia.

Life Cycle

• All carpet beetles pass through four stages: egg, larva, pupa, and adult.
• Depending on the species, each female may lay 40 to 90 white eggs which hatch in 8 to 15 days.
• Eggs laid indoors are found in lint accumulations near the food source, in air ducts, under heavy furniture, behind baseboards.
• After hatching, larvae begin their destructive feeding, avoiding light and molting several times as they develop.
• They may spend 60 days to a year or more in the larval stage, depending on species, type and amount of food available, and temperature.
• When rooms are warm indoors, the life cycle is shorter than in an unheated portion of the house during the winter.
• In the spring, the pupal stage is followed by new adults.
• The life cycle ranges from 1–3 years, depending upon the environmental conditions. The black and variegated carpet beetles usually have only one generation per year, but other species may have three or four generations per year.
• The life expectancy of the beetle is about two weeks.
• If the beetles are inside homes, the adult beetles usually lay their eggs in air ducts, in closets, under furniture, or under skirting boards. If the adults are outside they will lay their eggs in the nests of birds or tree hollows.

Feeding and diet

The larvae are responsible for the damage of various items in homes, such as furniture, clothing, blankets, furs, and carpets.

The larvae are also a major pest in museums as they attack dried animal skins.

The adult beetles feed on the pollen and nectar of flowering plants and live mostly outdoors.

Other behaviours and adaptations

The larvae of Australian Carpet Beetles are small hairy grubs whose hairs break off when handled and can cause allergic reactions in some people. Before we introduced household goods into their diet, carpet beetle larvae naturally fed on spider webs, dried animal skins or other dried protein material.

Control methods

As a result of the adults living mostly outdoors, treatment indoors is ineffective in the long term because the adult beetles easily re-enter and infest buildings. Vacuuming should be thorough and frequent with particular attention paid to carpet edges and areas covered by furniture.