Earwigs

A new month, and a new project. June brings with it a focus on earwigs. Specifically, the Earwi’GO! BuzzClub earwig research. The aim of the work is to create different earwig hotels, and investigate their preferred habitats. Longer term, the goal is to support gardeners in establishing earwig friendly garden areas. Earwigs’ value as pest controllers, cleaners, and pollinators far outweighs the minor damage they can cause by eating soft plants. The hope is that by identifying their preferred housing, earwigs can be given some assistance with accommodation, away from areas of the garden that they are less welcome. Further details, including how to join the project, are below.

History

There are around 2000 known species of earwig worldwide, of which four are native to the UK. Fossils dating back 208 million years found in Australia and England are thought to be from the ancestors of modern day earwigs. This fell during the Triassic period, when the first dinosaurs evolved. Earwigs, or their ancestors, have survived two mass extinction events during their time on Earth!

Life

Nocturnal insects, earwigs favour dark, damp habitats such as log piles or leaves. They pair in late summer, and mate in the autumn. The female then retains the sperm until conditions are suitable to lay her eggs. Earwigs have a lifespan of around 12 months.

The mothers fall within the rare 1% of insects who make excellent parents. They are univoltine, meaning they have one brood per year (sometimes in two batches but from one set of fertilised eggs). The mother remains underground with her eggs, cleaning (to remove harmful fungus spores) and guarding them until the young hatch. If the eggs are scattered by other underground dwellers, the mother collects them carefully together again.

Of around 60 eggs, the hatch rate is high – about 77% – compared with 4% for untended eggs. Young earwigs are nymphs known as wiglets. The wiglets moult four to six times after their late winter/ early spring birth, each moult adding an extra segment to the antenna. The mother remains with them – feeding, cleaning, and guarding them – until after the second moult when she clears a route from the nest to the outside. At this point, the young may start venturing out to scavenge for food at night. After the third or fourth moult, they usually leave the nest permanently.

As they grow, females and males develop their cerci, or pincers. Male earwigs have large curved pincers, compared with the females whose pincers are straighter. Although they could give a pinch to human skin, the pincers are used mainly for holding prey, mating rituals, and defending themselves.

 

Project

Extra

• Research into nature/nurture found that wiglets raised without a mother were less nurturing towards their own young.
• The name earwig derives from the Old English word ‘earwicga’ meaning ‘ear creature’. It is thought that this name was attributed to earwigs because of the shape of their beautiful, shell-like (and rarely seen) wings. Contrary to urban myths, earwigs do not crawl into people’s ears and lay eggs.
• Earwigs are found on every continent except Antarctica.
• During his expeditions, Charles Darwin collected many specimens to support his theories. Some of his earwig specimens survive in collections to this day, including several at the Museum of Natural History in Oxford.

Much as I love earwigs and find them fascinating insects, I have none of my own photographs. Images for this post are credited, and were downloaded from Pixabay.