Classroom lesson ยท Wildlife ยท ๐Ÿ‡ง๐Ÿ‡ด Bolivia

Pink River Dolphin

The largest freshwater dolphin in the world โ€” and it really is pink!

A pink river dolphin surfacing in a brown Amazon river

Photo ยท Wikimedia Commons

What is it?

The pink river dolphin โ€” called boto in Bolivia โ€” is the largest dolphin that lives in freshwater rivers. Unlike ocean dolphins, it swims through the flooded Amazon rainforest. As it gets older, its skin turns from grey to a bubblegum pink colour, making it one of the most unusual-looking animals in the world.

Tell me more

Pink river dolphins have longer snouts than ocean dolphins, which helps them poke around logs and tree roots to find fish hiding inside. Their necks can turn further than most dolphins, so they can manoeuvre through tangled underwater forests. They are remarkably flexible and can bend their bodies in ways ocean dolphins cannot.

The pink colour comes partly from lots of blood vessels close to the surface of their skin โ€” you can even see them blush a deeper pink when they are excited. Males tend to be pinker than females. The older a dolphin gets, the pinker it usually becomes.

In Bolivian and Amazonian folklore, the boto is a magical creature. People say it can transform into a handsome person at night, come ashore to dance at parties, and then return to the river before dawn. This legend has helped protect the dolphins for centuries, because people do not want to harm a magical animal.

These dolphins are very intelligent and curious. Unlike shy ocean dolphins, botos sometimes swim up to canoes and seem interested in people. They use echolocation โ€” clicking sounds that bounce off things โ€” to find fish in the murky brown river water where they cannot see very far at all.

In the classroom

Walk your class through this in 15 minutes.

Talk together

Discussion prompts

  1. 01The dolphin's pink colour comes from blood vessels near the skin. Can you think of other animals whose colours come from what is inside their bodies?
  2. 02The boto legend has helped protect the dolphins. How can stories and folklore actually help protect wildlife?
  3. 03Pink river dolphins use echolocation to 'see' with sound. What would it be like to navigate the world using only your ears?
Try this

Classroom activity

Try echolocation! One child stands facing a wall and claps once. Listen to the echo โ€” does it come back quickly or slowly? Move closer and further from the wall and listen to how the echo changes. Explain how a dolphin might use this to understand the shape of its river environment.