Magpies 1 Blackbirds 0

We have a lot of Magpies kicking about, I don't really like them. I see them pestering the other birds, and in particular the blackbirds. When I've observed this happening, I've often gone outside and chased them away, but unfortunately it hasn't been enough to save these 4 eggs. I found this derelict nest in one of our bushes at the bottom of the garden, the parents had obviously had enough!