This South American otter is the world's largest, at some 6 feet long. It lives only in the rivers and creeks of the Amazon, Orinoco, and La Plata river systems.

These huge members of the weasel family swim by propelling themselves with their powerful tails and flexing their long bodies. They also have webbed feet, water-repellent fur to keep them dry and warm, and nostrils and ears that close in the water.

Fish make up most of the giant otter's diet. They hunt alone or in groups, sometimes using coordinated efforts, and must be successful often to meet their daily intake quota. Each animal may eat six to nine pounds of food per day. Fish are supplemented by crustaceans, snakes, and other