SEA OTTERS HAVE MANY GOOD QUALITIES
Q. You once said diamondback terrapins were your favorite turtle. What is your favorite mammal?
A. Tough question, because all puppies and kittens, indeed most baby mammals, are engaging. But sea otters qualify for my top 10 list of “most appealing adult mammals” and not just because they are cute. They are one of the most resilient animals in the world. In addition to living in a harsh habitat, they were nearly hunted to extinction for their fur.
These charming creatures come closer than other animals to being “unique,” which is not easy because you must be the only one in a category. Sea otters are not the only marine mammal, think dolphins, seals and whales, but they are the smallest in North America. They are in the weasel family, which includes badgers, skunks and wolverines, but are the only ones without the scent glands that produce a strong-smelling musk.
Sea otters are the only marine mammals with no blubber or layer of fat to survive in cold waters. Instead, they have the densest fur among all mammals (more than 1 million hairs per square inch!). The fur traps air, which provides insulation. Sea otters can weigh up to a hundred pounds, making them one of the heaviest members of the weasel family, but they can float with ease because of air trapped in the fur.
Their diet includes fish, abalones, sea urchins, crabs and other sea creatures, which they dive to the sea floor to obtain. Their lungs are double the size of most comparably sized mammals. They have been known to dive as deep as 300 feet and commonly stay under water for 2 to 4 minutes. Among the myriad traits setting them apart from other animals is their use of tools: sea otters are one of the few mammals known to employ tools. They use rocks to dislodge abalones, which attach themselves to hard surfaces and must be pried loose. Furthermore, a sea otter will swim on its back, set a rock on its belly and open the abalone shell by pounding it against the rock.
I once rubbed my hand over a sea otter pelt; it was the softest fur I have ever felt. Their fur is the reason for their near demise, initially at the hands of the Russians in the 1700s. In fact, the primary reason for the Russian occupation of Alaska before we bought it for a few cents an acre was the sea otter fur trade. At the time, sea otter pelts were considered the most valuable in the world.
The Russians recruited people native to the Aleutian Islands for the fur trade beginning in 1741, when the number of sea otters worldwide was estimated to be as high as 300,000. Until 1911 the unregulated killing of sea otters continued in most parts of the animal’s geographic range from northern Japan, across the Aleutians and down the U.S. coast to Baja California. In that year four nations—Russia, Japan, Great Britain and the United States—established a treaty to protect the species. At the time fewer than 2,000 sea otters were left in the world, and some estimates place the number as low as 1,000.
People came very close to wiping out this marvelous species through unsustainable harvesting. We had already finished the job on the East Coast with the sea mink, which became extinct in the 1800s because of overhunting for the fur trade. Sea otters are tough, but they take several years to mature, usually have only one pup, and can live more than 20 years. Taken together those factors mean the species cannot recover quickly from a population decline.
In the past hundred years the worldwide population has gradually increased. Although exact numbers are elusive, about 100,000 wild sea otters are estimated to be alive today. I am glad the sea otter is still around to be placed on my top 10 list of most appealing mammals.
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