Today's focus is on Oscar, a six-month old-giant otter who lives with his family in Cocha Salvador, a freshwater lake in the Amazon Basin in Peru, one of the most bio-diverse areas of rainforest in the world. Amazon giant otters really are giants. At nearly two metres long from nose to tail, they are the largest of the world's otters and the most sociable, living in noisy groups of up to 20. Giant otters are experts at high-speed underwater pursuit. They live almost entirely on fish, and together Oscar's family eat an amazing 25 kilos of fish every day. However, the murky lake waters hide a formidable enemy: the black caiman, a South American crocodile. When there is a caiman about, Oscar learns the importance of family.