Randy,
If Alaska Natives were the only people who had hunted whales it would be a non-issue and there would be plenty of whales. 
There wasn't enough of them left,after the invasion of explorers and whalers, thanks the exposure to small pox,measles, influenza, and TB to pose a threat to the extinction of whales.
Russians and Japanese showed up on their large whaling ships and slaughtered whales for the oil, the meat, and a few for other parts. Pretty similar to what happened to the American buffalo.
Currently, the Japanese and some Russians (damn those Russians, they pop up everywhere) are still "whaling" some legally and some illegally. 
 Native wale hunters are not the only killers of whales. 
Every year a cruise ship or two comes into port with a dead whale impaled on the bow.
Modernization of hunting gear may have increased the accuracy of the kill but the Native hunters still face adverse weather conditions and dangerous seas in small craft. Skill and experience is still needed.