Why do tiny lake animals commute between the surface and the dark?

What Crafty Clover says in this video

Intro

Hi there, curious minds! I'm Crafty Clover! Let's discover something amazing. Why do tiny lake animals commute between the surface and the dark?

The Big Idea

Tiny lake animals make a daily trip! Up at night, down by day. Why?

Night Feeding

Step one: Night Feeding. Many zooplankton rise to the surface at night to feed on algae. The top of the lake is where the algae grow.

Day Hiding

Step two: Day Hiding. In the daytime, fish can see them near the top. So the tiny animals sink to the dark depths to hide.

A Giant Migration

Step three: A Giant Migration. This daily trip is one of the biggest migrations on Earth, in total weight. That's true even though each tiny animal moves just a few meters.

A Closer Look

Let's take a closer look! Rise up. Sink down. Food above. Hunters.

Quick Facts

Quick facts! Sound-based sensors show waves of plankton moving up and down. Up at night. Down by day. Hiding from fish.

Think Like a Scientist

Now, think like a scientist! With a grown-up, fill a jar with pond water. Shine a lamp on one side. Watch the tiny animals. Do they move toward or away from the light? Return the water to the pond.

Outro

Many zooplankton rise to the surface at night to eat algae, then sink to the dark depths by day to hide from fish. Though each moves only a few meters, this daily trip is one of the biggest migrations on Earth by total weight. Science is amazing! What will you discover next? Every question is a new adventure, so keep wondering and keep exploring with me! Crafty Clover can be found on Amazon Books, Google Bookstore, and Apple Books. Available for purchase or download! Bye for now!