Fishing in your classroom
They have no ears. They hear anyway.
Sound travels about four and a half times faster in water than in air — and carries tens of kilometres. Water does not muffle noise. It carries it.
Do fish hear? They have no ears.
Does noise matter when you fish?
Why sound, and not sight?
Do all fish hear the same?
And if it sees nothing and hears nothing?
Can noise harm them?
Can you tell a fish’s age?
What the source does not say
An honest caveat: the department’s page on underwater noise deals mainly with marine animals and industrial noise — ships, sonar, construction. Nowhere does it say that talking in a boat scares fish away. We will not make it say so. What is established is that fish hear, that sound carries far underwater, and that excessive noise harms them.
For the teacher
- The otolith is the best thing on this page. A stone in the head that records one ring a day for a whole year — a fish carries its own diary.
- Ask why sound beats sight underwater before opening the card. Pupils usually work it out: you cannot see far in water, and smells drift.
- The swim bladder card links two things that seem unrelated: floating and hearing. The same air sac does both.
- Read the yellow box with the class. The temptation here was to conclude “so be quiet in the boat”. The source does not say that, so neither do we — and noticing the gap is a skill.