Swallows eating the bees

I'm fed up with the swallows, they have now left the nest and all of them sit on the wires and swoop down over the hives for a feast on my bees. I think I was too kind in the spring letting them build and reuse the nests in the sheds and the loft. I think after they fly away in the autumn I will break down the nests and discourage them from nesting around here next year.