If the bee disappeared off the surface of the globe then man would only have four years of life left. No more bees, no more pollination, no more plants, no more animals, no more man.
They are no disappearing from my garden as I keep them fed every years with plenty of flowers ;-)
I read an article regarding the issue of bee population decreasing in California and according to the latest it sounds like the issue is related to lack of food variation. Having more type of flowers helps the bees.
So make sure we have different flowers so the bees in the area enjoy some nice meal ;-)