Another harbinger of spring! These are carpenter bees and although I read the males lack stingers, I hate them! They will eat your house, your deck, your lawn furniture, whaterver kind of unprotected wood they can find. Actually they don't eat it, but burrow nice little perfectly round holes in the wood for nests, and if there's a lot of them and you don't stop them, they can do a lot of damage. Bublebees, however, nest in the ground and do a lot of good pollenation, if you don't mess with them. Bumblebees have striped abdomens, not the shiny black of these fellows.
These were hovering above the patio, staking out territory and looking for nesting sites and mates. I hate it when they hover right in front of my face, challenging me on my own property, even if the males don't sting.