Unlike whales, seals, and most other marine mammals, Sea Otters lack a layer of blubber to keep
them warm. Instead, air bubbles trapped beneath their fur help to insulate them.
Sea otters have extremely luxurious fur coats – thicker than any other mammal. Their
very soft underfur has up to 1 million hairs per square inch (394,000 hairs per square centimeter).
This is covered by an outer layer of longer guard hairs.
Otters also stay warm by quickly burning energy with high metabolic rates. This
requires that they eat 20 to 25 percent of their body weight each day.
Sea urchins and abalone
are favorite foods, along with crabs, mussels, scallops, cephalopods, fish, chiton, and snails.
They often eat shellfish by floating on their backs and breaking the shell against rocks that they
place on their stomachs.