Research

Giant Otters have been the subjects of several detailed studies since the 1970’s. The first in depth field research on the species was carried out by Nicole Duplaix in the late ‘70’s and Elizabeth Laidler in the early ‘80’s in small blackwater rivers of the lowland rainforest of Suriname and Guyana, respectively.

In 1980, Brigitte Fugger carried out a field season of research on one resident family of Giant Otters at Cocha Cashu Biological Station in Manu National Park, Peru. From 1980 to 1984, Martha Brecht and Talia Llosa were directed by Charles Munn in field research in Manu on three otter families, one of which was the Cocha Cashu group. These groups were the first families of this shy species to become totally accustomed to human observers. The otters, which out of curiosity even sniffed the hands of the researchers, carried out all the most intimate aspects of their family life in full view of the researchers including copulation, nursing of the babies, carrying the babies by the scruff of the neck from den to den, teaching the babies to swim, sharing injured fish with the babies, and extended preening of each other. This team recorded 2,000 hours of close range observations of these three otter families in 1980-1984.

Parallel to the detailed observation of the three habituated families, in 1980 and 1981 Munn carried out short surveys for Giant Otters on all 13 lakes of the lowlands of the Manu National Park. Armed with these surveys, Munn successful defeated a government plan to promote market meat hunting, skin hunting, and live monkey harvest from the lower half of the Manu River. Munn argued that controlled ecotourism in the lower Manu River would be a more sustainable land use than the proposed hunting and monkey export. By 1984, the Peruvian government adopted Munn’s recommendations as the official policy for the lower Manu River.

Between 1984 and 1990, Munn directed a WCS-funded Peruvian field team that carried out ongoing Giant Otter surveys in all 13 lakes of the Manu National Park, including the three tourism lakes (Salvador, Otorongo, and Juárez) as well as 10 lakes off limits to tourism. This team, which amassed 3,000 contact hours during this period, found that eight families of otters (about 60 individuals in all) were using the 13 lakes. In Manu, Giant Otters lived and fished primarily in the lakes rather than in the nearby river, which they used only as a highway to travel between lakes. Of all the lakes of the Manu, only Salvador was big enough and deep enough to feed an otter family all year, while the remaining 12 lakes each were used between 10% and 60% of the days of the year by the other otter families. Only Salvador had a family of Giant Otters resident every day of the year, which made that lake and that otter group particularly important for structured, successful otter tourism.

Between 1990 and 2005, Christof Schenck and Elke Staib and more recently their younger colleagues, Frank Hayek and Jessica Groendjick, have carried out the most comprehensive research yet on Giant Otters in SE Peru. Schenck and Staib surveyed all the otter groups in the Manu National Park, recording up to 70 individuals in about eight groups. In the latter part of the 90’s and up til 2005, their team, which is funded by the Frankfurt Zoological Society (FZS), has surveyed Giant Otters in all the river systems in a 90,000 square kilometer region of the Peruvian rainforest. Their team has amassed many thousands of hours of otter observation, and they continue to search for otters in ever remoter corners of the rivers of SE Peru. This FZS research group has been critical of the WCS otter tourism model in Manu and has managed to close down traditional otter tourism in some lakes and sections of lakes in SE Peru (see section on Ecotourism).

GIANT OTTER RESEARCH IN BRAZIL AND TOPICS FOR FUTURE RESEARCH.

Parallel to these efforts in Peru, researchers in the Nichare River in Venezuela, in parts of the rivers of SE Colombia, and the Brazilian Amazon and Pantanal have carried out long term observations on Giant Otters. By the early 90’s, the leading project on Giant Otters in the Pantanal of Brazil was directed by Brazilian/Swiss conservationist Jorge Schweitzer. Mr. Schweitzer studied and protected wild otters on his large cattle ranch in the Rio Negro region of the south-central Pantanal of Brazil. To this day, Mr. Schweitzer and now his daughter and son-in-law continue the tradition of otter conservation and research at their property in the heart of the Pantanal.

In 2001, the Brazilian Ph.D. Miriam Marmontel of the Sociedade Civil Mamirauá began long term studies of several families of Giant Otters on the rivers and lakes of the Fazenda Sete Ranch in the Miranda region of the southern Pantanal. Her work is ongoing at this time.

In 2003 and 2004, Ms. Carolina Ribas earned a Master’s Degree based on her detailed surveys and behavioral observations of 15 Giant Otter families in the SW and NE Pantanal of Brazil. She worked closely with Professors Guilherme Mourão and Walfrido of the Brazilian Research Institute EMBRAPA, which has an important pantanal research center based in the city of Corumbá, Brazil.

In the Balbinas Reservoir in the northeastern part of the Brazilian Amazon, excellent, detailed research is being carried out now by a team of Brazlian researchers on a large number of families of these otters.

One area of research that deserves attention now by researchers all over tropical South America is how to carry out the most exciting, most sustainable, and most ethical tourism with this amazing carnivore. Simultaneously, it is critical to study how to limit or control mining-related mercury pollution in the tropical rivers of South America. Otters are notoriously sensitive to mercury in the fish they eat, and gold mining in many rivers of the Amazon, Pantanal and Orinoco basins is making the fish toxic and very dangerous for Giant Otters and humans alike.