Garden avian struggles

I decided to fed the birds in the back garden, so I put out a simple peanut hanger. Suddenly five or six jackdaws arrived and regardless of any interference happily settled in. No other smaller birds appeared. After a while I thought it might be good to give the others a chance, so friends gave me a small-bird feeder only and I put the other in a sort of cage the jackdaws could not enter. There was a time when the jackdaws kept returning but then they gave up and the smaller birds flew in. A robin at first, then blue tits, then a couple of similar size to the tits but with black and white heads (I do not know what they are) and a sparrow or two. All seemed to be going well. However every so often the jackdaws reappear and sit on the gable by the garden and then swoop in if they see any others around. The small birds rapidly disappear. I am not really into seeing animals in an anthropomorphic way, but I can see how writers do and there appears to be a version of the Sopranos going on in the back garden. The doves appear but seem to be simply opportunists in the battle picking up what others have left. It doesn’t help the jackdaws’ case that up-close they have a rather sinister look about them.