Contrary to the name of this insect, the earwig doesn’t crawl into the ears of people. Earwigs are completely harmless for people. In addition to the common earworm (Forficulauricularia L.) we have four other species in our country, although they are much less common.
The common earwig is a 10 – 14 mm long, lean insect with a horizontal, somewhat flatted body. It is glossy brown, the head is darker and the legs are lighter. Characteristic feature is a rod-shaped organ in the abdomen. This rod is primarily used as a defence weapon. In the common earwig, it doesn’t play a role in capturing insects. The rod-shaped organ is longer in the males than in the females. Adult earwigs have wigs, however they hardly ever use them. Earwigs have mouth elements allowing them to chew plant elements. Soft leafs and fruit (such as strawberries) can be eaten.
Lifestyle and development
The common earwig can be found underneath all kinds of waste, under rocks, in compost heaps, flower pots, mole piles and decayed trees, between the leafs of cabbage plants, under old boards and frequently in flowers, especially those of the Dahlia. The earwig is a nocturnal animal and requires certain humidity, without which the animal can’t live. The animal is most comfortable at an average temperature of 26 – 33°C. However they have great adaptive abilities, due to which they exist from sea level up to the mountains. Forficula auricularia L. mainly feeds on vegetable material, such as fungal spores green algae, lichens and other mosses, petals, soft leaves and unripe seeds. In addition, they also consume rotting animal material and dead or defenceless insects, but also living aphids and small caterpillars.
Interesting is that the earwig is involved in brood care. Before the winter begins, they mate. In the fall, usually in November, the female digs a hole, where it hibernates. The eggs are laid in the spring. As soon as the egg laying stage has commenced, the female develops a strong breeding instinct. In 2 – 4 days, the female lays 20 – 80 eggs on a heap at the end of the burrow. Once the eggs have been laid, they are carefully protected against enemies by the female. The eggs are frequently licked, and with her mouth parts, the eggs are transported to another place in the burrow when she feels that the location of the eggs is not suitable for some reason. Slowly, the brood care reduces. By then the female is often very weak and will soon die, after which she is eaten by her own hatchlings. The entire development from egg to adult animal takes 5.5 to 8 months.
Prevention & Control
Often, earwigs invade houses, caravans, tents etc, in particular when it is very dry outside. They look for places that have the humidity they require. Proper earworm control consists of sealing cracks and seems in the exterior wall and sealing ventilation ducts with a solid grid or fine mesh. Compost heaps and other organic material in the immediate vicinity of the house in particular, must be cleaned. When one suffers nuisance from earwigs, the best thing to do is to catch these insects and release them elsewhere or to kill them with boiling water for instance. Capturing is possible by placing moist cloths, rags or folded burlap outside at night. Also effective is placing flower pots upside down, loosely filled with mildly moist wood shavings, straw or hay. Under the edge of the flower pot, one places a rock or stick to allow the insects to crawl into the pots. However, these measures are often not enough A treatment of the area in which these insects hide with insecticides is extremely ill-advised. The earwigs that hide during the day cannot or hardly be reached, whereas such a treatment can kill other insects and birds. This means that the natural enemies of the earworms are killed as well and that the control measure has the opposite effect.