What Is Making All That Noise at Night? Identifying Katydids and Crickets

Step outside on a warm night in late summer and the darkness is loud — a pulsing wall of buzzes, rasps, and chirps that seems to come from everywhere at once. It is one of the signature sounds of the season, and it is not a single insect but a whole nighttime chorus. Unlike the cicadas that drone through the heat of the day, these are the singers of the night, and with a little practice you can pick out who is who by ear.

Day Chorus vs Night Chorus

A useful first split is timing. The loud, whining buzz that swells and fades in the daytime treetops is almost always cicadas. The chorus that takes over after sunset and runs deep into the night belongs mostly to katydids and crickets — relatives of grasshoppers that "sing" by rubbing body parts together (a process called stridulation) rather than with vocal cords. Sort by time of day first, then by the character of the sound.

Katydids: the Raspy "Katy-Did" Chorus

Katydids produce the harsh, rhythmic, scratchy sound that dominates many late-summer nights, especially from trees and tall shrubs. The most famous, the common true katydid, repeats a raspy phrase that people have long heard as "Katy-did, Katy-didn’t" — a coarse, insistent, back-and-forth from high in the canopy.

• Sound: raspy, mechanical, and rhythmic, often in two- or three-pulse phrases repeated over and over
• Where: mostly up in trees and dense shrubs, which is why you hear them far more than you see them
• The singer: large, leaf-green insects with long antennae and wings shaped and veined exactly like a leaf — superb camouflage that makes them very hard to spot
• Other kinds: coneheaded katydids add a steady, buzzy, almost electrical drone to the mix

Crickets: the Chirps and Trills

Crickets fill in the more musical parts of the night chorus, and there are two broad camps worth knowing:

• Field and ground crickets — the familiar clean "chirp… chirp… chirp" from lawns, gardens, and near foundations (and the classic culprit when one gets indoors and keeps you awake)
• Tree crickets — pale green and delicate, they produce a soft, continuous, pulsing trill from shrubs and trees that many people mistake for a background hum rather than an insect

A fun trick: the snowy tree cricket is nicknamed the "thermometer cricket." Count how many chirps it makes in 13 seconds, add 40, and you get a rough temperature in degrees Fahrenheit — a real relationship, because these cold-blooded insects call faster as the air warms.

Why They Sing — and Why It Peaks Now

In nearly every case the singers are males, calling to attract females and to stake out territory. The chorus peaks in late summer and early fall because that is when this year’s insects have reached adulthood all at once, and warm nights keep them active and calling. As nights cool toward autumn, the chorus slows and thins — the same insects, chirping more slowly in the cold, until the first hard frosts bring the season’s song to an end.

None of these nighttime singers bite, sting, or pose any threat. They are harmless neighbors making one of the most evocative sounds of late summer, and a cricket that wanders indoors is a nuisance at worst.

Put a Name to the Sound

Sound is only half the puzzle — the other half is finding the tiny green musician hiding on a leaf. If you track one down, or a cricket turns up on the porch or in the house, take a photo and Spotter will identify what it is and tell you which part of the night chorus it belongs to.