In the swim

Activity overview

Run the activity

1. You’re going to watch a short video. The aim isn't to find right answers, it's to explore ideas and find out what they know.

• Do they know what might happen based on the image?

2. After you've watched the video, lead a discussion with your class:

• What different fish did they see?
• How do these animals move through the water?
• Why are they coloured or patterned differently?
• Why do some fish live in shoals and others live alone?

3. Ask the class to describe what they saw using only one word.

Background science

This clip shows a range of fish in a range of habitats, from tropical seawater to cold freshwater in Alaska. For the list of fish please see scroll to the credits at the end of the page, but note that while sharks and eels are fish, dolphins are mammals and are not fish.

Pink jellyfish are found in warm Mediterranean seas and are approximately the size of a small plate.  They swim by contracting and relaxing the muscles around the bell, propelling themselves forward. Fish use their caudal fin (tail fin) to propel themselves through the water. Other fins are used for balance or to change direction.   Water is drawn in through the mouth and passed over gills to extract oxygen.

Dolphins and salmon can leap out of the water. Dolphins may use porpoising (swimming fast and close to the water surface or jumping through and above it) to aid navigation, to keep together in their pod, locate fish shoals or communicate.Salmon move from sea to freshwater rivers to spawn and must adapt to changes in salinity. They leap to overcome obstacles as they swim upstream to their spawning grounds.

Brightly coloured tropical fish blend in well with the colours of the coral reef whereas eels and rays may be patterned to disguise themselves against the stony floor, both to escape predators or to aid ambush of prey that they may be hunting. Eels are very flexible and can swim through narrow channels in the reef.  Corals are colonies of animals too, that feed on microscopic plankton.

Take it further

Follow up on this activity by encouraging children to group and sort the different animals featured in this video, and explain their reasons for the groups they choose. Can they suggest the food chains that they are part of, too?

Explore more about why a dolphin is a mammal with this Odd One Out Say cheese or take a closer look at a fish with this Zoom in Zoom out activity Grey and black.