The Giant Otter lives in the rivers of the South American rain forest and is one of the most endangered species in South America. Along with the wolverine and the sea otter, the Giant Otter is also one of the three largest animals in its group. And with a body length of 1.5 - 2 meters, it is the longest of all river otters.

Another special feature of the Giant Otter is their highly developed social behavior. They live within groups of up to 10 individuals, who hunt, sleep, and play together. The groups are composed of a parent couple with their young of several years. A group occupies a confined territory, and the territories of different groups do not overlap. The Spanish name is "Lobo Del Rio" or "river wolf" having to do with their social behavior. There is also no other otter species in which males and females live together.

After a pregnancy of 65-72 days in the dry season between May and September, otter females give birth to one to four cubs. Usually, only the dominant female of a group reproduces. All group members, however, help with raising the young.

During the first two months of their lives, the cubs stay inside the den. Otter groups are noticeably more alert and careful than usual when caring for their young. Today we also know that females under stress stop producing milk so that the young starve to death within a couple of days if the mother is constantly disturbed. At the age of two to three months the Giant Otter cubs join the group hunt for the first time. Young Giant Otters reach sexual maturity at two to three years of age. At that time they began to leave the family group. They roam their home range on their own for awhile and then leave. It is interesting because both males and females leave the group at the same age. The Giant Otters then goes on and occupies their own stable home range where they stay year round. A Giant Otter home range includes at least one lake, usually several smaller creeks, and part of a river.

The oldest documented life span was 8 years for free-ranging Giant Otters and 14 years for ones in captivity.

An ecosystem is like a chain if you take away one link the chain is broken. Every plant and animal has a purpose and interacts with other species. If it were to disappear the ecosystem may be destroyed, especially if a larger species like the Giant Otter were to disappear many things would be lost.

Giant Otters are at the top of the food pyramid in the tropical rainforest. Similar to the jaguar, puma, black caimans, anacondas and Harpy Eagles, adult Giant Otters need not fear any enemies.

Big predators mostly catch sick, old, and weak individuals, and thereby keep a population or pray in a healthy condition. It is likely that otters also fulfill this function and contribute to maintaining healthy fish stocks.

Habitat destruction has clamed a lot from the Giant Otter because they inhabit the waters of the tropical rainforest. Since humans like to settle along the water, aquatic habitats are the most affected by humans. So basically Giant Otters are among the animals most exposed to human activity. New settlements also mean the clearing of the forest, fishing, water pollution, and hunting. To this day, the largest threat to the Giant Otter is habitat destruction.

Increased tourism is another potential problem for otters. Tourism is both a blessing and a threat. It brings money and attention to help conservation of otters. At the same time, unwitting tourists in motor boats can come too close to the dens of otters. If tourists are not careful, the stress of people invading their range can cause mother otters to stop producing milk and the cubs can starve to death.

During the last 15 years efforts in Peru have been underway to preserve the habitats of Giant Otters. Conservation organizations have worked closely with local land owners and indigenous Indians for the protection of this endangered species.

Under strict control there are several places in the Manu Wilderness and the Tambopata region of the Amazon where tourists can view these beautiful creatures in their native environment. Notably on the lakes surrounding the Manu Wildlife Center and Manu BioStation, on the upper reaches of the Manu River in the Manu Reserve Zone, and especially on the Sandoval Lake in Tambopata.

In the northeastern Peruvian Amazon, 100 miles west of Iquitos, the Giant Otters of the Pacaya-Samiria National Reserve can be observed. The Amazon Refuge Lodge provides access to the Pacaya-Samiria Reserve.