In fact it turns out the majority of bee species (75% in the US and Canada according to the Science News article) are solitary. They're starting to get a lot of attention for use as crop pollenators since populations of regular hive bees seem to be in decline.

Speaking of bees dying, if you haven't seen this Youtube video of 30 hornets killing 30,000 bees, you better watch. If you really need the narration here's a lower quality version in English.