What Is the Sensory Organ on a Fish for Feeling Vibrations?

In addition to their sense of touch, fish use a special organ to detect even minute vibrations in the water surrounding them. This sensory organ is called a lateral line organ, and it is found in all aquatic vertebrates, including fish. Being able to feel vibrations in the water from a distance allows fish to find food and avoid enemies.

  1. Lateral Line Organ

    • The lateral line organ runs from the fish̵7;s head all along its body and consists of a series of sensory cell clusters called neuromasts. Located either on or just underneath the skin, the neuromasts contain sensory hairs. These hairs are surrounded by a gelatinous cupula that bends in response to water moving around it.

    Canal Specialization

    • Some fish that spend their entire life swimming or that are exposed to constant strong currents develop canal specialization. They have canals running just beneath the surface of the skin where the neuromasts are housed. The cupulae are protected inside these fluid-filled canals and are exposed only through pores along the lateral line. This helps prevent the fish from having overstimulated neuromasts from their constantly moving environment.

    Ampullary Lateral Line Organ

    • In some fish, including sharks and rays, the lateral line organ is capable of sensing electrical currents. In this case the sensory cells are deep in the skin in the bottom of surface ducts. The ducts are filled with a substance that is conductive of electricity. This allows these fish to detect the small electrical charges from other fish and living creatures in their environment. Ampullary lateral line organs are sensitive to not only electrical charges, but movement and vibrations in the water as well.

    Staying Safe

    • The lateral line organ is crucial for a fish to get around safely in his environment. It prevents collisions with other fish, helps them find food and avoid other fish that might make a meal of them. Along with the lateral line organ, a fish̵7;s skin is filled with nerve endings that can react to pressure or temperature changes. Fish pair this with the ability to sense the salinity of the water around them to stay out of dangerous waters.