The Amazon River Dolphin
What and How the River Dolphin Eats
*echolocation: location of objects as reflected by a sound emitted by animals which are able, such as dolphins or bats.
*average body weight: in females the average weight is 154 kg, and in males the average weight is 100 kg.
Physical Features & Movement
Color: pale pink or grey
Flexible neck, unlike other dolphins
Longer rostrum than other species of dolphins (both freshwater & saltwater)
Unlike other dolphins, they do not have dorsal fins; instead they have a dorsal ridge.
Moves by shifting tail verticallyMax. speed in water: 18 mph
- 2 - 3 meters in length (72 - 98 inches or 6 - 8 feet)
Weight: 220 - 440 lbs
Life span: 12 - 18 years
Poor vision; relies on echolocation to maneuver in the water and to locate meals, prey, and predators.
The pectoral fins are homologous to the arm or hand bones of a human.
River Dolphin Full Body
The flexible neck, extensively long rostrum, and dorsal ridge, which distinguish this type of dolphin from any other, are visible here.
River Dolphin Embryo
Embryo before birth
Behavior & Social Life
River dolphins reproduce in a period of time that extends from the end of October to the beginning of November, and are pregnant from nine to twelve months.
Families become very attached to each other in these pods.
Social politics are visible in these large groups, but this order is not determined by violent acts. Violence, as it is observed in captivity, mainly occurs when there is a situation resulting the showing of the dolphins' more protective side for a mate or injured family member.
They are active at both day and night and have been observed in somewhat of an alliance with the gray river (tucuxi) dolphin and giant otters while in pursuit of their next meal. In the wild, they are curious animals, however difficult to train in captivity and more reserved than other species of dolphin.
The amazon river dolphin is sedentary and does not move themselves, or their pod, very far throughout 1-2 years unless necessity is shown at any time other than during migration season, which are small lapses of time that occur throughout the year. Territory battles are not regular, so home ranges are assumed to be large and to overlap each other throughout the lake.
To attract a mate, male river dolphins will wave a tree branch above the surface or strike rocks or chunks of clay against the river bottom, both while making noise.
*Mating: river dolphins do not mate for life, only for a season, however sometimes will travel with their families in a pod.
Habitat and Environment
*Traditional Amazonian myths make the river dolphin out to be an animal that can morph into a handsome human wearing a hat (for the purpose of hiding its blowhole), seduce and impregnate young women, and then return to the water as a river dolphin again. They are also said to capture some of the women or children and take them back to the other encantados. Eye sight with one is supposed to curse a human with nightmares for the rest of their lives.
Dam-building, fishing net entanglement, boat traffic, and pollution contribute to the constant decline in population.
As the fishing economy improves, the amazon river dolphin population declines. The river dolphin appendix is considered a delicacy, however to prevent further danger of the animal, international trade of it has been prohibited by CITES, along with ASCOBANS, CMS and these animals are protected under the Indian Wildlife Act.