The sea otter (Enhydra lutris) is a marine mammal native to the coasts of the northern and eastern North Pacific Ocean. Adult sea otters typically weigh between 14 and 45 kg (31 and 99 lb), making them the heaviest members of the weasel family, but among the smallest marine mammals. Unlike most marine mammals, the sea otter's primary form of insulation is an exceptionally thick coat of fur, the densest in the animal kingdom. Although it can walk on land, the sea otter lives mostly in the ocean.

In this Monday, March 10, 2014 photo, a 9,000 year-old mask is on display at the Israel Museum in Jerusalem. The exhibition called “Face To Face” shows eleven stone masks, said to have been discovered in the Judean desert and hills near Jerusalem, which date back 9,000 years and offer a rare glimpse at some of civilization's first communal rituals. (Photo by Tsafrir Abayov/AP Photo)

Smithsonian National Zoo biologist Leigh Pitsko releases a male lion cub for its swim test in the zoo habitat moat, in Washington May 6, 2014. Four, unnamed ten-week old lion cubs were tested today for their ability to swim and remove themselves from their zoo habitat moat. (Photo by Gary Cameron/Reuters)

“These eerily stunning images taken using infrared lighting reveal the landscapes of Iceland in all their natural glory. Andy Lee, 45, uses a special technique which blocks out light from some visible wavelengths and picks up light from others invisible to the naked eye”. – Caters News. Photo: Location: Kirkjufell. These eerily stunning images taken using infrared lighting reveal the landscapes of Iceland in all their natural glory. (Photo by Andy Lee/Caters News)

Jolon Clinton, 15, (L), and her sister, Halcy, 17, take photos of a fissure near their home on the outskirts of Pahoa during ongoing eruptions of the Kilauea Volcano in Hawaii, U.S., May 14, 2018. (Photo by Terray Sylvester/Reuters)

A woman is having a massage at the Lukacs Bath in Budapest, Hungary June 28, 2016. Hungary's capital owes its popularity as a tourist destination partly to its numerous hot springs and bathing culture which have drawn visitors to the area since Roman times. Bath houses range from large, ornate 19th-century buildings like the Gellert and the Szechenyi to tiny Ottoman Turkish-era hamams, some of them more than 500 years old. (Photo by Bernadett Szabo/Reuters)

People wait in line to pay their last respects to the late Fidel Castro in Havana, Cuba, Monday, November 28, 2016. Cuba's government has declared nine days of national mourning following Castro's death on Nov. 25. (Photo by Fernando Medina/AP Photo)

Sierra “Lovely Amazin” Redd of Greensboro, North Carolina, poses for bikers by a custom Suzuki Katana on Ocean Boulevard during the 2015 Atlantic Beach Memorial Day BikeFest in Myrtle Beach, South Carolina May 24, 2015. (Photo by Randall Hill/Reuters)