About the Amazonian Manatee
The Amazonian manatee is a large aquatic mammal that lives exclusively in the Amazon basin of South America. Though it can grow to 9 feet long and weigh 800 to 1200 lbs, it is the smallest of the manatee species. Unlike other manatees, which can be found in both salt and fresh water, the Amazonian manatee never ventures out to the sea from its fresh water home. A shy plant-eater, the International Union for the Conservation of Nature (IUCN) lists it as a vulnerable species because of past commercial hunting and the general destruction of its habitat.
The Facts
The Amazonian manatee, Trichechus inunguis, is part of the order Sirenia, which includes the West Indian manatee, the West African manatee, and the dugong. These animals are all known as sea cows, although they are in fact more closely related to elephants than to any other land mammal. Like elephants, manatees are herbivorous, and captive Amazonian manatees eat 20 to 35 lbs of food per day. In the wild, however, they often fast for weeks during September to March, as this is the dry season in the Amazon basin, and vegetation is less abundant. Because of their large fat reserves and slow metabolic rate, Amazonian manatees can survive for up to 7 months with only very minimal food intake.
Amazonian manatees are largely solitary creatures, though they have been observed in groups of 4 to 8, generally while feeding. Calves stay with their mothers for up to two years, and mothers are often seen with young calves on their backs or at their sides, with the mother's flipper protectively around the calf. Multiple births are extremely rare, and calves are born approximately every two years.
Like other aquatic mammals, manatees breathe air, and will surface several times per minute, with only their nostrils rising above the water while the rest of the body stays submerged. However, they can go up to 14 minutes without taking a breath.
Features
All of the manatee species have some similar basic features, including a paddle-shaped tail, walrus-like bristles on the mouth, front flippers, and thick, slightly wrinkled skin which is gray or gray-brown in color. Manatees also periodically grow new molar teeth throughout their lives; the teeth come in at the back of the jaw and gradually replace the old teeth in the front of the mouth. This trait is unique among mammals.
Amazonian manatees are notable for several distinctive physical features including a pink or white patch of skin on the chest, and the fact that they have no fingernails on their flippers. Their species name, inunguis, is Latin for no nails.
Size
The Amazonian manatee is the smallest of the manatee species. It can grow up to 9.2 feet and weigh between 700 and 1200 lbs. By contrast, the more familiar Florida manatee can be over 15 feet in length and weigh up to 3300 lbs.
Risk Factors
Having no natural predators, the Amazonian manatee is threatened only by human activity. Once hunted primarily by natives looking for food, they were later killed by commercial hunts for oil, fat, and especially their skins, which were used to produce hoses and machine belts in the 1930s and 1940s. Now they are imperiled mainly by habitat destruction and climate change, which can produce droughts and restrict their movement and food supply. They are also subject to drowning due to entanglement in commercial fishing nets, not unlike dolphins were before the advent of dolphin-safe tuna.
Geography
Countries: Ecuador, Peru, Columbia and Brazil
The Amazonian manatee is found throughout the Amazon, its tributaries, lakes and lagoons. However, since it prefers the parts of the ecosystem known as blackwater because of the large amounts of vegetation found there, the manatees are concentrated largely in the specific areas that best meet their nutritional needs.
