Amazon River Dolphin
The Amazon river pink dolphin with speckled skin pokes snout of water
chem7 / Flickr
The Amazon river dolphin—also known as the boutu, boto, or bufeo—has the distinction of being the largest of the freshwater dolphins, and happens to turn pink as it ages. In 2018, IUCN listed Amazon river dolphins as endangered.3 Primary threats include the use of them for fish bait, fishing with explosives, and contamination of the river water by mining operations.