Did you know a sperm whale can be heard an estimated 10,000 miles away? Sperm whales, also called cachalot, are the largest-toothed predator and loudest animal on earth; their vocalizations are about 230 decibels.

To put this into perspective, the human eardrum will burst at 150 decibels, and an estimated range of 180-200 could even cause death. Water amplifies all that is heard, making a whale’s sounds even more intense. Their clicks are so powerful, nearby underwater divers can feel the resulting vibrations pulse through their bodies. You can rest easy, though: despite owning this death sound superpower, sperm whales are unlikely to use it to kill a human. 

One sound can mean quite a lot. Each click a sperm whale makes may contain a whole paragraph of information. These clicks they create are part of the whale's language, and they can be used to locate objects around them by reflecting their sounds off the water, called echolocation. 

These whales are far from the only animals that communicate underwater. Other sea dwellers do so using a variety of visual, auditory, tactile, chemical, and electrical signals. Sharks, for example, have highly sensitive hearing and can hear up to 820 feet away. They can hear low frequencies that are not audible to humans. Octopus and other cephalopods like squid have an organ called the statocyst for hearing and balance, while dolphins communicate using high pitch whistling and clicking, helping them both communicate and gain a sense of their surroundings.

It is fascinating to learn how other inhabitants of this planet communicate!