How adorable are these South American river dolphins – residents of the mighty Amazon River? But do not be fooled. These guys are the apex predator in this habitat. They evolved from marine species of dolphins and live in fresh and brackish waters.
They may have entered the Amazon via the Amazon Delta from the Atlantic or the Pacific before the formation of the Andes. Either way, these guys are now a long way away from the sea! In this clip, we get to learn all about this cute killer species.
Watch the Fascinating Clip Below
Why Are Freshwater Dolphins Pink?
Experts believe that the pink coloration is scar tissue from repeated abrasions. The injuries are caused either by games that get a bit out of hand or by fighting over resources. Female river dolphins are attracted to the pink color – perhaps it makes their potential mate look tough?
How Rare Are River Dolphins?
There is some debate over the exact taxonomy of river dolphins. Nevertheless, the general opinion is that there are only a few living species left. They include the Bolivian river dolphin, the Araguaian dolphin, the Orinoco river dolphin, and the Amazon river dolphins featured in this clip. As a group, they are commonly called botos. All of them are endangered or critically endangered. Threats to their populations include dam construction, shipping, and getting caught by accident by fishing vessels.
Which Is the Largest Freshwater Dolphin?
The Amazon pink river dolphin is the largest of this group of dolphins. They can reach nine feet in length and weigh up to 400 pounds. To maintain their weight, they have a diverse diet made up of more than 53 animal species. As we see in this clip, this includes piranhas!
How Are Freshwater Dolphins Different from Marine Dolphins?
Marine dolphins such as the bottle-nosed dolphin have body shapes that have evolved to move through the water at speed. This is because they have to hunt for fish in open water and travel long distances. They also have double-slitted eyes that work well in and out of the water. Marine dolphins can dive to depths of over 140 feet because that is where a lot of the fish are.
In contrast, botos live in bodies of water where the levels can fluctuate vastly. They need to be able to hunt for fish in shallow water on flood plains. The problem with floodplains is that they contain a lot of obstacles! Therefore, the dolphins need to be small enough and agile enough to get around them. They are therefore about half the length of their marine relatives.
The photo featured at the top of this post is © COULANGES/Shutterstock.com
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