Why Do Crickets Chirp at Night?

The sound is made by rubbing wings

Many male crickets produce a call by rubbing a scraper on one forewing against a row of ridges on the other, a process called stridulation. The resulting song has a pattern that can help a female recognize a male of her species. Washington State University explains that the main purpose of many cricket calls is to find mates. [1]

Darkness and body clocks shape the timing

Crickets are often active at night, and some species begin calling as light levels fall. Research in field crickets shows that stridulation follows a daily rhythm and can be affected by nighttime light exposure. Different species have different schedules, so nighttime singing is common but not universal. [2]

Temperature can change the song

A cricket’s chirp rate often changes with temperature, and males may call more slowly in cooler conditions. This is why the sound can seem different from one night to another. The insect’s species and environment matter as much as the time shown on a clock.

The call changes with species and temperature

Cricket songs are species-specific signals, so a chorus may contain several different rhythms and pitches. Temperature affects the rate of calling in some species, which is why the same insect may sound faster on a warm evening than on a cold one.

Other insects coordinate signals in different ways. Some fireflies synchronize their flashes, while crickets generally produce calls for nearby listeners. Both examples show how sound or light can carry information at night.