Happy Sea Otter Awareness Week! As the seemingly infinite number of sea otter gifs to be found on the internet reveals, these marine mammals are extremely adorable. But there’s a lot more going on below the surface. Here are four essential facts about sea otters:
They’re the largest member of the weasel family
Mustelidae, a family of fur-bearing mammals that includes everything from weasels to honey badgers, also includes a subfamily composed of both freshwater otters and sea otters. Although they’re the second-smallest sea mammal–partly because they employ thick fur rather than blubber for insulation–they’re the largest member of the weasel family, according to Defenders of Wildlife.
They’re messy eaters
Because they don’t have blubber, sea otters eat constantly to make up for the energy they lose staying warm, and they’re slobs about their food, writes Josh Silberg for Hakai Magazine. The areas where they feed are littered with chunks. After diving for sea urchins, Silberg writes, the sea otters open their food “by ripping it apart with their paws or banging it with a rock that they use like an anvil. Once the urchin is pried open, the otters slurp up the nutritious, mustard-colored gonads as best they can before diving back for more. A mess of uneaten urchin bits floats in their wake.”
Recently, in an area re-colonized by sea otters, researchers observed unusual behavior from the otters' neighbors as a result of the mess. Sea-going Harlequin ducks were taking advantage of their ocean companions’ terrible table manners, he writes, by cleaning up after them. It’s unusual, he writes, because ducks would usually avoid a big predator such as a sea otter, and it likely won’t last for long–after a few years in an area, sea otters have generally eaten most of the local urchins and move on to other, less interesting prey.
Male sea otters do gruesome things to baby seals–and female sea otters
Male sea otters sometimes attack baby seals and attempt to mate with them, writes Brian Switek for Slate. These assaults often result in fatal injuries to the seal pups, he writes–and otters are similiarly rough with female sea otters. “Male sea otters typically grasp the female from behind and bite her face, and this rough behavior was associated with the deaths of about 11 percent of dead sea otters discovered between 2000 and 2003,” he writes.
A possible reason for the violent behavior towards seal pups is that some male otters are unable to win in the animals’ competitive mating process, leaving them without an appropriate female to mate with.
Cat poop is bad for them
Researchers at the UC Davis School of Veterinary Medicine have spent two decades studying the mystery of why a parasite which only cats carry, Toxoplasma gondii, was causing sea otter deaths. In that time they’ve established a definite link between sea otter deaths and animal feces, writes Justin Cox for a UC Davis publication. But it took more time to understand how the cat-poop parasite was making it into otters.
The UC Davis veterinarians' most recent research shows that development that causes runoff, such as paving areas or building new homes, can speed the transmission of bacteria to the ocean.