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How do dolphins use echolocation when water is dark or murky?

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Animals communicate by sending and receiving signals. For example, a mother dingo (Canis lupus dingo) can communicate certain types of information to her pups by using tactile signals conveyed through grooming. — Animal communication Animals communicate by sending and receiving signals. For example, a mother dingo (*Canis lupus dingo*) can communicate certain types of information to her pups by using tactile signals conveyed through grooming.

Dolphins navigate and hunt in dark or murky water by using echolocation, a biological sonar system that allows them to "see" their surroundings through sound.12

When visibility is poor, dolphins emit a rapid series of high-frequency clicks, typically ranging from 50,000 to 200,000 hertz. These sounds are produced using specialized structures in their nasal passages and are focused through a fatty organ in the forehead known as the melon. As these sound waves travel through the water and bounce off objects, the returning echoes provide the dolphin with detailed information about the size, shape, distance, and texture of their environment.31

This ability is so effective that dolphins can successfully catch prey at night or in highly turbid water where vision is limited. Research has demonstrated that dolphins can make fine discriminations between objects even when their vision is completely excluded, proving that echolocation serves as a highly reliable sensory tool for orientation and foraging in challenging aquatic conditions.3