@bonifartius i guess this depends on where you live.
@Sibylle smack in the middle of nowhere.. there are some stray cats already. i think it is fine, still, it like birds very much too.
Since birds (generally) fly, they have a fair advantage over cats.
Also, I had a house cat that was so "humanized" that after catching a mouse, it played with it for a while, then let the mouse and go to get some food from us humans. "Killing? Eating raw meat?? ME???"
@bonifartius @niclas i prefer having some side catch over using poison for mouse control.
I guess cat birth control is crucial. Feral cats are terrible to the environment.