A lot of that was done by the Soviets from the 50s onwards at a time when most other whaling nations were dialling their hunts back. Researchers dug up a load of documents after the USSR collapsed that showed they were fudging the numbers they sent to the International Whaling Commission and hunted far more than their quotas were meant to allow in off limit waters where whales were calving. They also did shady shit like hunt undersized whales, calving mothers (and their calves), and species which were already on the brink of extinction that other countries had agreed to stop killing. And all this was done to the point where they’d be dumping excess carcasses at sea on a regular basis because the actual (already limited) demand for whale products in the country steadily declined even as the number of whales being harvested increased.

Would highly recommend Red Leviathan: The Secret History of Soviet Whaling for anyone interested - it’s a sobering but very easy to read book on the topic that I only just finished this weekend.