Purely by chance I found that magpies in our garden love pasta twirls I buy it from Morrisons, put it in a pan and cover it with warm water. It softens and in the morning I put it in a funnel on one of my bird holders. All the birds love it and there is a steady stream of magpies, jackdaws, robins, sparrows all taking turns . Now they are feeding young the magpies sometimes drop the pasta into the bird bath ,leave it a few minutes then fish it out and fly off with it to feed their young.Now I am not saying that all magpies will eat pasta but it definitely works for us and they seem to leave the baby birds alone .I also put left overs and sometimes dog food mixed with the pasta out for them. I always thought that Magpies were a dominant species but the pigeons seem to have the better of them . It isn't too expensive to feed them on pasta ---30 pence packet from Morrisons does one day, sometimes two. Their spaghetti is only 20 pence a packet but the little blighters seem to prefer the twirly pasta.I am not saying this will work for all magpies but I think by filling them up it might deter them from killing the baby birds.