What bug comes every 17 years?

Answered by Douglas Hiatt

The bug that comes every 17 years is the cicada. Cicadas are fascinating insects that have a very unique life cycle. Unlike most insects that have annual life cycles, cicadas have a much longer cycle of either 13 or 17 years.

During most of their lives, cicadas remain underground, feeding on sap from tree roots. They spend this time in their nymph stage, which is the juvenile form of the insect. Nymphs are wingless and resemble small grubs or larvae.

After spending years underground, cicadas emerge en masse when the weather gets warm. This phenomenon is known as a “brood” and can be quite spectacular. The emergence of these large numbers of cicadas is referred to as a “cicada emergence” or “cicada outbreak.”

When the time is right, the nymphs crawl out of the ground and shed their exoskeletons, transforming into mature adults with wings. The empty exoskeletons, or “shells,” that they leave behind can often be found attached to trees or other surfaces.

Once they have fully emerged, the adult cicadas spend a few weeks above ground. The males produce loud buzzing and clicking sounds to attract females for mating. The sound of cicadas is a familiar and often nostalgic sound of summer in many parts of North America.

Mating takes place during this short adult stage, and the females lay their eggs in tree branches. After the eggs hatch, the tiny nymphs drop to the ground and burrow into the soil, where they will spend the next 13 or 17 years underground, completing their life cycle.

The reason for the long, prime-numbered life cycle of cicadas is still a subject of scientific study. One theory suggests that the long life cycle helps cicadas avoid predators, as they are difficult to predict and synchronize with. This may increase their chances of survival and successful reproduction.

There are several different broods of cicadas, each with its own unique emergence schedule. The most well-known brood is Brood X, which emerges every 17 years in parts of the eastern United States. This brood last emerged in 2021 and will reappear in 2038.

Experiencing a cicada emergence can be a memorable event. The sheer number of cicadas, the loud buzzing sounds, and the sight of the empty exoskeletons covering trees and surfaces create a unique and awe-inspiring spectacle of nature. It’s a reminder of the incredible diversity and adaptability of insects and their ability to thrive in various environments.

The bug that comes every 17 years is the cicada. Their unusual life cycle, marked by long periods spent underground and synchronized emergences, makes them a fascinating insect to study and observe.