Our bird feeders are hung on the shed,on a birdtable,in the middle of my obelisk which is ideal as the smaller birds can fly in and out of the roses and berberis but not the larger birds ;) and I bought a shepherds type ?crook and pushed it into the ground near the window and hung fatballs from it.
We get the occasional cats who sit on the shed roof watching the birds

but so far that's all they do!
My parents have bird feeders attached by 'suckers' to their window panes,it makes a mess on the windows but the birds have become very brave and as my Dad has poor sight he loves watching them feed up close,but maybe this would be teasing your cat?
Jacqueline :)