How Do Fish Hear?
Do fish have ears? How do they know when you're coming toward them? How do they hear sounds that can mean danger?
Fish don't really have external ears, yet they can hear. How can this possibly be?
Fish in the wild often know exactly where fishermen are at any given moment. That's because they hear the anglers. When they hear fishermen walking on the shore or hear their boats nearing the places they like to swim, they can dart away to a safe place in no time at all.
Vibrations in the ground and water rattle the nerves of fish. Experience has shown these fish that different vibrations mean different things. They know the difference between the vibration of one of the other fish in their school and the vibration of a predator. Once the vibrations reach the bones of the fish, the sound travels into their skulls, where ear stones (tiny stones in a fish's nerve hairs) tell the fish that there's a sound they need to be made aware of.
These ear stones behave much in the same way human ears behave. Humans have inner ears made up of tiny grains of calcium carbonate. These substances are called otoconia. Humans also have bones in their inner ears. These bones are to humans as the ear stones are to fish.
You can, in effect, talk to fish, and they do have the capacity to learn. As long as they can hear the vibrations rattle through their bones, they know that you are communicating with them.
Many anglers know fish can hear. That's why they like to go out into the middle of a stream or lake when fishing and stand there or sit there for hours on end in hopes the fish will rise. As long as you don't make a sound, the fish may not see you (as long as the water is cloudy enough). Your goal is to not ruffle the water at all, talk or move above the water much, so you won't create any vibrations and alert the fish that you are in the area.