The amazon river dolphin is a small dolphin that can be found swimming in the Amazon river.
This dolphin is one of several species among the river dolphin family.
The others include:
- The Chinese river dolphin
- The Ganges river dolphin
- The Indus river dolphin
- The franciscana (la plata) dolphin
All dolphins with the exception of the franciscana dolphin (la plata dolphin) live in fresh water rivers.
The franciscana dolphin lives in or near the coastal shores in saltwater.
Physical Characteristics and Appearance
The Amazon river dolphin can vary widely in terms of color.
The most we’ll known and common colors for these marine mammals is gray and pink, however depending on their age and level of maturity their skin can turn various shades of white, yellow, pink, brown or gray.
When it comes to size these dolphins can grow to be over 8 ft. in length, but are typically smaller in size.
In terms of weight some dolphins can grow to weigh as much as 450 pounds or more, however as with their height these dolphins are generally smaller and lighter weighing between 180 – 220 lbs. on average.
The body is fairly streamlined and thickest near the middle.
To assist with swimming they have a small dorsal hump for stabilization and a pair of curved flippers to help with swimming.
Because their vertebrae isn’t fused or connected the way other mammals are these dolphins can turn their head a full 90 degrees allowing them to fully view their surroundings.
In addition to their flexible necks they also have a long beak which allows them burrow their mouth into logs and narrow spaces where they can catch their prey.
While the possess eyes they are believed to have poor eyesight when compared to other dolphin species due to the fact that they have evolved in shallow, dark, murky waters where eyesight plays less of a role.
Instead of navigating with their eyes these marine mammals use echolocation to help them get around and hunt their prey.
Diet and Hunting Methods
They are often seen swimming at or near the bottom of the river hunting for crustaceans and may use their beak to capture other prey that is hiding in hollow logs or other objects.
Catfish and piranha are also considered a regular part of their diet and in some cases they may be observed hunting small turtles.
Migration and Habitat
The amazon river dolphin can be found swimming in south America throughout the amazon and Orinoco rivers.
They can also be found inhibiting the rivers of Brazil, Columbia, Ecuador and Peru.
During the rain season when the river’s flood with water these dolphins travel through the marshes and forests in search of food.
These dolphins can be observed inhibiting several thousand square miles during these floods.
When the water levels lower they return back to the rivers and river banks.
Social Structure and Communication
Unfortunately not much is known about the social structure of these river dolphins.
These dolphins are known to communicate using a well structured variety of high and low range click and whistles.
Depending on the river dolphin the length, frequency and range of their clicks and whistles can vary quite a bit.
The variations in sounds are not only used to communicate different things but also help these dolphins distinguish individual members within their pod.
These sounds are most often used during times of hunting in the form of echolocation or when they want to communicate a need or desire to another dolphin.
Reproduction and Lifespan
The average gestation period (the period from conception to birth) for amazon river dolphins is about 9 months.
Most births occur during the summer time between July – September.
These dolphins tend to be very closely connected to their family, at least in their early youth.
Newborns can usually be seen swimming along with two or more adults for the first several months after birth.
During mating season the female dolphins can be found traveling deep into the forests (possibly to avoid the highly competitive male dolphins).
The males have been known to attack one another during these periods when in search of a mate and may end up fighting one another over a female dolphin.
Due to the fact that these dolphins live in shallow river waters their main threats are humans.
Pollution, boats, construction and accidental fishing hazards all contribute to the endangerment of these dolphins.
Unfortunately some populations of river dolphin have become highly endangered and may become extinct in certain areas if severe measurements aren’t put into place to protect these dolphins.
When it comes to the entire Amazon river dolphin species there is inconclusive information regarding their endangered status due to insufficient data.
When it comes to predators most dolphin species that have predators usually face threats from killer whales and/or large sharks.
Because the Amazon river dolphin lives in the river it is not known to be hunted by these types of animals.
Instead the amazon river dolphin may be hunted by other animals that inhibit the Amazon.
Animals that have been observed hunting and/or eating these dolphins include anacondas, caimans and jaguars
10 Interesting Amazon river dolphin facts
1) The amazon river dolphin is one of around 4 known species of freshwater dolphin.
2) These marine mammals are the largest dolphins among the freshwater species.
3) The pink amazon river dolphin is believed to be the most attractive of all amazon river dolphins and faces the most aggression among males during mating periods.
4) Because these marine mammals live in rivers rather than the open ocean they aren’t known to have oceanic predators such as killer whales and sharks which are known to hunt dolphins that live in oceanic saltwater environments, but they may face threats from other animals that inhibit the Amazon.
5) The amazon river dolphin is also sometimes referred to as the Boto dolphin.
6) Since the amazon river dolphin is a marine mammal it is warm-blooded, breathes air, produces milk and gives birth to live young.
7) The amazon river dolphin makes up one of around 80 known species of cetacea.
8) The neck of the amazon river dolphin is un-fused so it can move its head a full 90 degrees.
9) Rather than a tall dorsal fin these dolphins have a low triangular hump-shaped ridge down the middle of their back.
10) The female amazon river dolphin can grow as much as 3 ft. longer than their male counterparts.