About the episode
Tourists do it and now it seems fish are using it too: saving energy by moving in a group.
In the case of cyclists, it’s a headwind, while in the case of fishermen, it’s a countercurrent. You might think someone would have already investigated this in detail, but these scientists say they’re the first to approach it this way.
Why do fish swim in schools? So that was still an open question. Yes, of course it also provides more protection, but would it also cost less energy?
To find out, they built a whitewater fish trail in the lab, complete with all sorts of smart cameras, the ability to control the current and a device that can measure how much oxygen the fish are consuming.
They were able to observe that when the fish swam in groups of eight, they used 79 percent less energy than individual fish. Whether the water was turbulent or calm, the more brutal the conditions, the more they began to swim together.
They saw a difference between turbulent and calm water in individual fish. They used 22 percent more energy in turbulent water.
So it’s possible that energy saving is one reason why fish swim in schools in the first place. Not a bad idea, since this tactic is more common in biology. And even in sperm cells on their way through the reproductive tract, they’ve already seen it in previous research.
Read more about the research here: Swimming in schools may help fish save energy in turbulent waters.
