Date and cause of Extinction
During the 18th and 19th century the true rulers of the Russian Far East (and later also of Russian Alaska) were the "Promysleniki"*)'promysel' = hunt, notorious fur dealers who plundered the once abundant animal populations. They subdued the indigene people and demanded sable furs as tribute payments*)Laws existed, requesting fair treatment of the indigene people, but: "The sky is high and the Tsar is far". Soon one area after the other was looted, and one had to look out for new unexploited territories. In this situation broke the news about the St. Peter survivors, who had brought with them 700 magnificent otter furs, fetching exorbitant prices on the Chinese market, and who told the world about the abundance of fur bearing animals in the eastern ocean.
Nothing could stop the Promyshleniki now. Hastily they equipped dozens of hunting expeditions. Since Kamchatka was not able to provide for such year-long trips*)Vasili Silov in Heptner 1974, S. 49, the hunters spent the first winter on Bering Island, killing seacows and salting their meat and blubber.
Besides the meat, fat and oil, they also utilized the hides to cover their Baidars, light boats carrying up to 20 persons. They only brought the wooden keel and frame.
From the island they continued their raid, plundered the Alëuts and the Pribiloff Islands and explored the Alaskan coast. Again the indigene people were enslaved and exploited.
By habit these adventurers hunted the seacows as if their numbers were infinite. The Russian mining engineer Yakovlev, who was sent to Copper Island to assess the possible exploitation of the ore, reported 1755*)in Domning 1978, S. 163:

“For hunting them, abought eight men ride in a whaleboat, one of which has on a long rod on which is attached a wide and long strip of pointed metal (it is called a pokolyuga [ = a jabber or sticker]), with which he stands near the stern in front of the sternsman, and the others sit at the oars and when they reach alongside the head of the cow and the standing one with the pokolyuga gives a hearty wound to that sea beef, and the rowers with the whaleboat have to hurriedly row away from the cow so that that stabbed cow would not break up their whaleboat with its tail as well as with its flipper. And thus this stabbed beef, with a hearty wound not swimming for long in the sea, becomes exhausted and stopping at a spot turns its belly upward. And the hunters tow the carcass to the shore and cut it into pieces ...

One cow's meat provided food for 33 men for one month.*)Waxell wrote that the meat of one cow fed his 46 men for about 14 days ...

And further it was observed how ... hunters ... in small parties of two or three ... cause exceeding waste and loss to those cow herds ... since a man from among them going out not far into the sea, stabs and mortally wounds one or another cow; but those wounded cows go out to sea, and there, when they become exhausted from their wounds, then the sea does not wash [them] up on shore quickly ... [their meat will] become useless as food ... And thus this hunting ... although they stab many, not one fresh one comes into their hands, and ... they suffer hunger, and [still] cause eradication of the cow herds. ...in the future ... they should be ... prohibited, by an ukase*)an imperial instruction from destructively hunting sea cows in small parties ... in order that Komandorskiy Island would also not become empty, as is Medny*) Copper Island now found to be empty."

No Ukas was enacted, and 1768 the last lonely animal was killed.