Seeing the Ocean With Sound
Dolphins have good eyesight, but in the dark, deep, or murky ocean, eyes only get you so far. So how do they find fish, dodge obstacles, and navigate at night or hundreds of feet down? They use an incredible natural sonar called echolocation, which lets them “see” the world with sound. Here is how this amazing ability works.
Clicks and Echoes
Echolocation works like the ocean’s version of radar. A dolphin makes rapid clicking sounds and then listens for the echoes that bounce back off objects around it. By timing how long the echoes take to return and reading their strength, the dolphin can build a detailed picture of what is out there, even in total darkness.
The Melon and the Jaw
The clicks are produced inside the dolphin’s nasal passages, just below the blowhole. They are then focused and aimed by a fatty organ in the forehead called the melon, which works like a sound lens. When the echoes return, the dolphin receives them through fat-filled channels in its lower jaw, which carry the sound to its inner ear. It is a beautifully designed system.
Echolocation at a Glance
- Dolphins send out clicks and listen for the returning echoes.
- The melon in the forehead focuses the sound into a beam.
- Echoes are received through the lower jaw and inner ear.
- From echoes, a dolphin can judge size, shape, distance, and even density.
What They Can “See”
Echolocation is astonishingly precise. From the returning echoes, a dolphin can tell not just where something is, but its size, shape, speed, direction, and even whether it is hollow or solid. This is how spinner dolphins can hunt small fish in the pitch-black deep water off Oahu at night, then rest during the day. It is a sense far beyond anything humans have.
Experience It on a Tour
When you watch wild dolphins on an Oahu tour, remember there is a whole hidden world of sound around them. On some trips you may even hear their clicks and whistles through the water. Ask us and we will help you find a responsible dolphin tour where you can appreciate these amazing animals and their incredible senses.