Otters are amphibian relatives to martens. Their body is stretched and covered with the thickest fur in all the animal kingdom. They spend most of their lives in the water where they also find their food. They have their lodges on land. Whilst diving, during which they are able to shut both their nostrils and their ears, these carnivores hunt for fish. Otters are excellent swimmers and divers. They can stay underwater for up to eight minutes.