Threats to the Giant Otter


Their fur is amonst the finest in the world, which nearly led to their extinction through overhunting. Since 1973 they have been listed on CITES Appendix I ie trade in their pelts is banned, but since a single pelt on the black market can earn an agricultural worker a whole year's wages, poaching is still rife. An animal that is extemely noisy, inquisitive, fearless and moves around in large groups is extremely easy to hunt. The alpha female is usually the one killed as she approaches first, leaving her litter to die, and disturbing the whole group's social structure. This is still a major threat to the species.

AN example of a Giant Otter skin can be seen on the Swiss Federal Veterinary Office website; this information is used for identifying illegal fur shipments.

Habitat Destruction

Loggers clear the rainforest and farmers move in. The soil is depleted within a couple of years and the farmers move on, but the forest takes many years to regenerate. Since development is mainly along river banks, this process has a major effect on giant otters, both by the destruction of suitable camp and den sites, and by human disturbance, to which they are very sensitive - it leads to cub mortality and the abandonment of ranges. Even increased river traffic can cause this unwittingly.

Habitat Fragmentation

The result of habitat destruction is that available ranges become isolated from each other. This means that when young otters go out to look for unrelated mates and suitable new territories to establish their own breeding groups they are unable to find anywhere. This obviously has a major impact and prevents multiplication of otter groups in any one area.

Water Pollution

Gold miners, many of whom are working illegally, use Mercury to extract gold from its ore. They then drive off the unwanted mercury by burning. The fumes fall on the land and are washed into the rivers, killing microorganisms, poisoning fish and magnifying through the food chain to concentrate in the tissues of the top predators - giant otters, caiman and man. The evidence from Japan shows that before gross toxic effects are observed, reproduction is heavily disrupted. Fish tested a few years ago by the World Wildlife Fund ranging from the Manu National Park to local fish markets contained mercury levels far exceeding legal maximums in the USA and Europe.
Fossil Fuel Extraction
Giant otters are as vulnerable to oil spills as any other aquatic mammal.
Agricultural Pollution
Runoff from the large soya plantations in South America can bring pesticides into the food chain. Again these concentrate in the tissues of the top chain predators, and are well known for disrupting reproduction long before mortality.

Tourism and Human Disturbance

Eco-Tourism is a two-edged sword. On the one hand it brings in money and discourages poaching, but it leads to development of the river bank for accomodation, viewing facilities and so on, and sewage effluent being discharged into the water systems, and leads to more river traffic. Even unwittingly, tourists can disturb the very creatures they have come to so to the point where the mother's milk dries up and cubs starve, or the whole group abandons its range. For example, in Manu National Park, six large lakes are both home to 75% of the otters in the park, and the most popular places for canoeing and touring the area. Careful and strict guidelines are needed for tourists, and education to encourage them to abide by those guidelines.

Pathogens of Domestic Animal Origin

All species of otter are very susceptible to canine and feline distemper, and canine parvovirus), and it kills them rapidly. The very presence of man leads to greater contact between wildlife and dogs and cats, introducing the threat of entire otter groups dying.
IUCN Paper


Despite appearances, the great rivers of South America are very easily overfished, and once the ecology is unbalanced, every lifeform is affected. Giant otters are deprived of their food, shot as competition, especially in overfished areas near habitations, and drowned in fishing nets. Logging and mining workers in isolated areas especially often cannot get enough protein, and shoot the otters as competitors they cannot afford.

Indigenous Use

Indigenous people use the otters for both food and fur, though apparently they taste horrible and are only eaten in desparation. The availability of modern weapons however makes the otter very vulnerable as it would not have been when it had to be approached using less effective weapons.

Pet Trade

Local people do take cubs for pets as they are very cute; this is often a sideline to poaching the rest of the group for pelts. As the pups grow, they develop enormous appetites and are aggressive when hungry, and even when not aggressive, their sheer size and natural weaponry make them untenable as pets for most people. The otters are then shot and skinned, or released unprepared into the wild where they will almost certainly die rapidly. Only the very lucky few, in Guyana in the region of the Karanambo Ranch, can be handed in for rehabilitation to Diane McTurk.


Giant otters are very big, very noisy and move in large groups. They are very inquisitive, and many of their calls are quite explosive in sound, so they appear angry when they are merely curious. Settlers, travellers and explorers wrongly believe they are under attack and shoot to defend themselves (as they believe). Again, it is the dominant female who is most likely to perish, disrupting the whole group and dooming her cubs.

Giant Otter