I could be mistaken, but i remember hearing somewhere that scientists discovered the cause of this problem. Something to do with a small worm that was incubating in their brains and as it grew larger and more mature it would literally drive the bee insane. The bee would then fly away from the hive to die as its brain was being reamed out by this parasite.
I could be entirely mistaken, but that's what I heard.
\You do not need a US Passport to travel to Canada.
Did you read that correctly? It states the following: Canadian law requires that all persons entering Canada must carry both proof of citizenship and identity. A valid U.S. passport or passport card is preferred... etc.