Why do sea otters hold hands?

So they do not drift apart. Sea otters sleep floating on their backs, and the current would carry them off one by one, so they rest in groups called rafts and sometimes hold paws.

They also wrap themselves in kelp, like tying a boat to a dock. And they have the densest fur of any animal, up to a million hairs in a patch the size of a stamp, which is what keeps them warm with no blubber at all.