Would somebody enlighten me regarding the life history of the local ladybug?  This afternoon our whole block looked like a scene from Hitchcock's "The Birds", only from ladybugs.  I've never seen them swarming like this before!  Is this the mating season?  
Another thing I noticed was that they were aloft with no apparent interest from birds.  Not one winged predator around for the hour or so I watched.  Are ladybugs distasteful to birds?