There are 13 species of otter and each is named after either where it lives, like the Eurasian otter, or after its physical attributes like the hairy-nosed otter.
Otters are related to ferrets and badgers and can be found across the entire globe. The smallest is the Asian short-clawed otter that can be as small as 70 centimetres (two feet) long and weigh as little as five kilograms (11 pounds). At the other end of the scale, the giant otter can reach lengths of 1.8 metres (six feet) and can weigh up to 30 kilograms (67 pounds).
Some otters can live in salt water, like the sea otter that never has to venture on land in its entire life. Most otters can like in either salty or fresh water and go where they find most food.
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