Perhaps of all the mammals in the Amazon River, none have a relationship with humans quite the pink river dolphin. The pink Amazon River dolphin, also known as a boto, is the most intelligent of all freshwater dolphins.
Pink River Dolphins inhabit muddy, stagnant water. They can reach up to ten feet long and weigh up to 200 pounds. Even though they live in the muddy water, as the floodwaters begin to retreat, some dolphins become stranded in small pools deep within the forest. They are however extremely flexible They can turn their head 180 degrees, which helps them swim easily through the forest in search of prey.
Pink dolphins hunt alone during the high water season. At other times, they are found in small family groups of 5-8 individuals. They mostly feed on crustaceans, crabs, catfish, and small fresh water fish. They have excellent eye sight which helps them locate prey in clear water. In murky water, they emit a series of clicking noises, 30 to 80 per second. The clicking sound bounces off objects, and the dolphins use eco-location, like sonar, to find their prey.
Botos are born grey and become pinker with age. And the skin of an Amazon River dolphin is not actually pink, it is clear. The pink color comes from the anima's blood showing through its skin. But the color pink changes depends on the dolphin's mood. Scientists believe that when a dolphin becomes excited, the pink color brightens like your face when you blush.
For further exploration, check out the following web sites.
Wilderness Classroom's Rainforest Library
BBC's Animal Facts
Information on all five species of river dolphins