Starlings are a terrible invasive species here in the USA. They are, of course, only doing what is natural for them-- they are opportunistic. But they are really doing a number on our native birds.
Anyhow, there are three options I know of in this situation. If folks have other options maybe they can share. One thing I'd suggest never doing is using a poison.
You can shoot them or have someone else shoot them, if firing a pellet gun is legal in your area (check your laws). They aren't stupid birds and you don't need to kill them all for them to learn to avoid the area. This will sound really weird, but people eat other wild bird species... if you live in a more rural area and you know the starlings are eating a good diet (i.e. not human trash), they are actually pretty good with a slice of bacon wrapped around the breast and cooked.
You can trap them live-- they make some really nice starling traps these days. The problem with this method is that you will need to dispatch them after trapping them. Releasing them just makes them trap-smart, and transporting them doesn't do much as they can fly long distances, and it may be illegal. It would certainly be irresponsible, as well, given that they are invasive.
You can move your chicken feed indoors (inside the coop) ... this usually deters them. If this does not deter them OR if you cannot move the feed inside, the only way to keep them from it that I know of is to keep your chicken in a run and cover the run with hardware cloth.
Best wishes!
