Giant Otter Ecology and Conservation in the Araguaia river

Responsible Institute:

National Institute of Research in the Amazon

In partnership with the National Institute of Research in the Amazon, this is the first Project involving giant otter capture, radio transmitter implant in the species and its monitoring through radio telemetry.

Despite its ecological importance as a top predator, there are still many gaps in our knowledge of the biology, ecology and conservation of the giant otter (Pteronura brasiliensis). With the general goal of researching this information, the Giant otter Ecology and Conservation Project was originally initiated in August 2006 in the Cantão State Park, Tocantins state, and is currently being developed in the reserve “Meandros do Rio Araguaia”, Goiás state. This project is a partnership of the Jaguar Conservation Fund/Instituto Onça-Pintada and the National Institute of Research in the Amazon.

At present, two animals have been captured (a male and a female) and had radio-transmitters surgically implanted in the intraperitoneal cavity. Although widely used in otters and nutrias, this was the first time that radio- transmitters had been implanted in giant otters. The results of monitoring showed that the animals leave their burrows on average around 6am and return at 6pm. Group home range was estimated to be 16.25 km².

The technique of radio-telemetry is providing a library of important and previously unknown information about the ecology, habitat use and movement patterns of this species.


We thank Prof. Dr. Luis Claudio Lopes Correia da Silva, FMVZ-USP for the his support in the first surgery to implant the radio-transmitter in a giant otter.