Saturday, November 30, 2019

Hydrodamalis gigas, or the last of the Sirens

On Remembrance for Lost Species Day (today) I'll take a look at Steller's sea cow, a sirenian related to the manatee and the dugong. As you can see in this image, they were er, plump and often weighed up to ten ton. They were much larger than their cousins, at between seven and ten metres long.

They used to live in the Bering Sea, gentle giants grazing the kelp beds in herds, apparently gregarious in company.

What finally brought the last of the Pleistocene mega-fauna undone, after millennia of Aleut people also hunting them, was the Western world's insatiable penchant for fur hats and coats. No, the sea cows were not furry. But sea otters are and the two species tended to live in the same areas.

"It seems that almost every aspect about these animals contributed to their decline. From their diet of kelp that forced them into shallow water, their social behaviour that put surviving sea cows in further danger, or the thick blubber that not only meant that buoyancy was always an issue but also made them apparently just so delectable."*

As one of the first western scientists to describe the species, German zoologist Georg Willhem steller naturally named sea cow after himself. Steller first saw a sea cow when the starving expedition crew were wrecked on Bering Island. He had the distinction of seeing the mammal both alive and dead and noted that if a cow was harpooned, the bull would follow her and try to ram the boat, copping another harpoon. 

Georg Wilhelm Steller begins his inspection of the female sea cow in 1742 
Photograph: Bering’s Voyages/

Steller's sea cows became extinct less than thirty years later in 1768. It's possibly an extinction hastened by ignorance as much as greed. The fur hunters seemed to be convinced that a lot more sea cows existed than actually did. The sea cows were in fact a remnant population that were previously unexploited, a lost tribe clustered in the shallows around the uninhabited Commander Islands. As Josh Davis explained in the quote above, Steller's sea cow was doomed from the moment their final refuge was discovered. 

In 2017, archaeologists and scientists with the Commander Islands Nature Reserves unearthed a near-complete skeleton. It's possibly the same sea cow that Steller and his crew butchered in 1742, starving, on the Great Northern Expedition of Vitus Bering. (Who also named a few things things after himself.)


  1. Some people believe that Mammoths still exist deep in the unpopulated parts of Russia.

  2. Replies
    1. I think this day of remembrance is really good. Last year was the first time I'd heard of it.

  3. Fascinating and sad. I'd heard of Steller's sea cow but not the day of remembrance. I agree it's good to reflect on what we've done, what we've killed off. It'd be nice to think we've learned from these losses, but the evidence isn't encouraging.

  4. Last day in November. It would be good to build more awareness of the day. Extinction is such a lonely but weirdly intriguing thing, isn't it? Loving your India work by the way.