Loudest Animals

World's Loudest Animals

Bushcricket

Using highly calibrated microphones, researchers recorded male bushcrickets in Colombia singing at frequencies of about 74 kilohertz. The human ear can hear in a range of about 20 hertz to 20 kilohertz.

The males produce sound through "stridulation," or rubbing their wings together. One wing acts as a scraper to rub against a row of teeth-like grooves on the other wing. (Watch a video of the bushcricket chirping.)

The bushcricket is notable for another reason: It had been thought extinct, said study co-author Ben Chivers.

Water boatman

Engineers and evolutionary biologists in Scotland and France recorded the boatman—which is roughly the size of a grain of rice—"singing" in a tank. The aquatic insect's songs peaked at 105 decibels, roughly equivalent to the volume of a pounding jackhammer within arm's reach.

The chirps are loud enough that humans can hear the sounds while standing at the edge of a boatman's pond. Fortunately for nature lovers, though, nearly all the sound is lost when the noises cross from water to air.

Remarkably, the boatman creates his songs by rubbing his penis against his belly, in a process similar to how crickets chirp. Sound-producing genitalia are relatively rare within the animal kingdom, but animals have evolved hundreds of other ways to boost their hoots, howls, and snaps.

Howler monkey

The monkey's volume comes from its enlarged hyoid bone, a U-shaped bone in the howler's throat that "isn't actually hooked to any of the [other] bones, so it kind of just hangs there," said Dell Guglielmo, caretaker for two howler monkeys at the National Zoo in Washington, D.C., said in 2011. The enlarged bone creates a throat sac in which the monkey's calls resonate before booming out.

The monkeys have a variety of calls, likely for communicating location, protecting territory, and guarding mates, but their vocabulary is yet unknown to humans.

Blue whale

Blue whales don't have songs as complex as those of humpback whales, but their low-frequency "pulses"—some below the range of human hearing—have been recorded more than 500 miles (805 kilometers) away.

A few years ago researchers found that the whales had been lowering the frequencies of their songs even more—by up to 30 percent since the 1960s in some populations. One theory suggests that the whales no longer need to sing at "high" pitches to be heard at a distance, because the species, while still endangered, has rebounded since whale hunting was banned in 1966.

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