Fish don't have ears that we can see, but they do have ear parts inside their heads. They pick up sounds in the water through their bodies and in the ear, according to the National Wildlife Federation.
A fish also senses movement in the water with the lateral lines that runs down each side of its body. Sharks, which are fish, have a keen ability to sense electricity. Oddly the genes that contribute to this ability are responsible for the head and facial features in humans, linking sharks and humans to a common ancestor way back in time.