Densest fur
Who
Sea otter, Enhydra lutris
Where
Not Applicable ()

The sea otter (Enhydra lutris) has the densest fur of any mammal, with around 100,000–400,000 hairs per square centimetre (650,000–2.6 million hairs per square inch). The world's sea otter population is found in colonies in the north-east Pacific, off eastern Russia, western Canada and western USA – particularly off the coast of Alaska, USA.