The Amazon River Dolphin Flushes A Brighter Shade Of Pink When It Is Surprised Or Exciting

Do you like dolphins? Dolphins are among the world’s oldest creatures, along with turtles, crocodiles, and sharks. When we think of dolphins, we usually don’t think of freshwater, but did you know some dolphins live in rivers?

Because of its unique coloring, the Amazon River Dolphin is also known as the boto or pink river dolphin. It is one of just seven freshwater cetacean species.

Dolphins from the Amazon River are only distantly related to dolphins from the sea. They’ve evolved bigger snouts with bristle hairs on the end, which are specifically specialized for river-bottom eating. Amazon River Dolphins, unlike their saltwater counterparts, have flexible necks and can rotate their heads left and right due to unfused vertebral column.

The dolphins do not have a dorsal fin like other dolphin species, instead, they have a long dorsal ridge.

The Amazon River Dolphin’s colouration is highly variable, affected by age and water clarity. Colours range from white/grey with a pink dorsal ridge and lighter below to a vivid pink! The sun’s rays make the dolphins lose their pink pigmentation so the darker the water, the pinker they will be.

When they are excited or surprised, the dolphins will flush more pink, similar to blushing in people!

Amazon River Dolphins are the only species of toothed whales to have different types of teeth in their jaw. Their back teeth are designed for crushing whereas their front teeth are pointy. They are the only dolphins in the world with teeth at the back which they use to crunch their food before swallowing.

The inflated portion of a dolphin’s head, which is roughly equal to their forehead, is known as a dorsal fin. The blowhole is usually located in the melon’s center. Small air sacs inside the melon are utilized to produce click vibrations. The melon focuses its ‘beam’ of clicks towards an object of interest, the sound then travels back providing the dolphin with information on the size, type, and speed of the object. This technique is called echolocation and is key for hunting prey.

River dolphins need to rise to the surface to breathe, just like all aquatic mammals.

Amazon River Dolphins are the largest of the river dolphins, they can grow up to 8ft but are usually smaller.

They can paddle forward with one flipper and backward with the other, making it easier for them to traverse through river floods. The dolphins will swim into flooded regions of land, and their agility allows them to easily avoid trees.

Amazon River Dolphins are often seen swimming on their backs, this thought to be due to their ‘chubby cheeks’ which obstruct their downward vision.

Dolphins are very intelligent animals; the Amazon River Dolphin’s brain capacity is 40% larger than humans! They are considered the most intelligent of the river dolphins. Amazon river dolphins are the most widespread river dolphins. The Amazon pink river dolphin is the most intelligent of all river dolphins.

Amazon River Dolphins were spared from human persecution as it was thought they had special powers, however, the dolphins are increasingly being viewed as unwanted competitors for fish. People will try and scare or kill the dolphins to prevent them from taking fish.

Except for humans, the Amazon River Dolphin does not have many predators, however, caiman, jaguars, and anacondas have been known to catch dolphins on occasions!

Mercury contamination from small-scale mining runoff is a serious issue for the Bolivian river dolphin. Catfish, an important food source for dolphins, are bottom-dwellers who are highly influenced by variations in water mercury levels.

Amazon River Dolphins are friendly and there are many stories among tribes in the Amazon of people being pushed ashore by dolphins when they were in the water!