The secrets of earwigs

PRESTON — I’ve long believed earwigs to be nasty vermin that snuck onto the Ark because I’m sure Noah wouldn’t have purposely saved them from drowning. Now my opinion has been slightly altered. Earwigs are nasty vermin for 2-3 months and the rest of the year they are neutral to even beneficial predators on other yard and garden pests. The difference?… Education.

The species we have in our area is the European Earwig (Forficula auricularia). It is one of about 2000 varieties worldwide. They are opportunistic omnivores, feeding on whatever plant or animal material is most readily available and tasty at the time. These pincher bugs, as they are sometimes called, have claw-like appendages called cerci protruding from the rear of their abdomen. These are used for hunting, defense and mating.

There are two fascinating attributes that I’ve learned about earwigs that were unknown to me before. First, the female tends and defends her nest of eggs and then young for the first two stages of their life. She regularly cleans the eggs to prevent fungal growth while waiting for them to hatch. Once the eggs hatch, she feeds and defends the young until they are ready to venture out on their own.

The second fascinating fact is that earwigs can fly. After recovering from that disturbing visual, I figured it wasn’t true because I’ve seen lots of earwigs and none with wings. Besides, where would they put them? The answer is the most intriguing. They have small elytra or wing covers on their back that mistakenly look like a simple thorax. Their thin, clear wings are folded origami-style under these covers and fold out to give short and unsteady flight. Consequently, they rarely take to the air.

Earwigs play an important role as a beneficial predator, eating mites, aphids, scale and other insects harmful to plants. Most of the year they make a living filling this predatory role while eating detritus, mold, and whatever else they find handy.

Unfortunately, these fair-weather friends turn into traitors once flowers, fruits and vegetables become available. While still enjoying an aphid appetizer, they like ripening fruit and garden produce as the main dish. Whatever is in season is what’s on their menu.

Dealing with this fickle behavior is difficult and frustrating. Many commercial insecticides list earwigs on the label. However, their habit of hiding and moving to new food sources makes consistent control troublesome. Non-selective insecticides also harm other beneficial insects like pollinators. Making various versions of pitfall and corrugated cardboard traps can be successful. Also, exclusionary tactics such as banding around tree trunks can be very effective if the earwigs are not already hiding within the tree canopy.