Dolphins are mammals which reside in sea and fresh waters. There are approximately 24 species of dolphins discovered of which most live in the seas and oceans, while just 4 species reside in river water. The pink dolphin is a fresh water mammal that lives in the Amazon River system.

They are found in most of the sea waters which have temperate conditions and where food is in plenty. They tend to remain in specific locations and migrate only in search of food, safer birthing areas and avoiding predators.

The fresh water varieties, of which the most popular one is the pink dolphin, inhabit the Amazon River and its tributaries in South America. They are even present in the Orinoco and Atabapo rivers in Venezuela; Amazon River in Brazil and Peru and Beni River in Brazil and Bolivia. They also inhabit waters of Rio Negro, Rio Tapajos and in the cloudy waters of the river Rio Solimoes. Unlike the gray dolphins which reach up to the beginning of the conjunction of the river with the ocean, the pink dolphin tends to inhabit the upper reaches of the Amazonian basins.

These beautiful and friendly mammals do not have any natural predators in the fresh waters. But humans have done the damage by disturbing the eco-system, excessive hunting, construction of dams and deforestation. Currently, pink dolphins are declared as a threatened species nearing extinction by the International Society for the Preservation of Tropical Rain Forest in South America.

As the name suggest, pink dolphins have a stunning pink coloration either on their complete body or just the under-belly. The average adult dolphin weighs approximately 200 pounds and measures seven to ten feet in length.

The physical traits of pink dolphins include a head shaped like a melon, absence of dorsal fin, having a humped back, unfused neck vertebrae, which permits the head to turn 180 degrees to maneuver through the flooded forests, long snout with sensors for detecting food on the floor of the river, large sized flippers in the front which enable swimming forward and backward and for crawling, and highly developed echo-location to facilitate navigation in the dark waters.

They feed on the fishes and crustaceans. They do not show any preference of the species of fish to feed on and have adapted by using their sharp teeth and powerful jaws to feed on spiny fish and catfish too.

They prefer to hunt and feed solitarily unlike their counterparts at sea. They use their long beaks with strong sensors. The prey present in the muddy river water gets detected by  echo-location, which gives an estimate of the distance the prey is from the dolphin and in which direction it is.

More Articles :

• Facts About Pink Dolphin
• How Do Pink Dolphins Protect Themselves ?
• What Are The Pink Dolphins Enemies ?
• What Is The Pink Dolphins Food Chain ?
• Where Are Pink Dolphins Located ?

eHow: What Is the Pink Dolphin's Food Chain?
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