Millions of bees have died this year. It's "the worst bee loss in recorded history," one beekeeper says

The U.S. beekeeping industry is in crisis over the shocking and unexplained deaths of hundreds of millions of bees over the last eight months. 

It's an unfolding disaster for the industry. Blake Shook, one of the nation's top beekeepers, has found tens of thousands of dead insects at his businesses. He said that he's never seen losses like this. 

"The data is showing us this is the worst bee loss in recorded history," Shook told CBS Saturday Morning.