Hi Mags
I also have mice visiting, they set the camera off frequently & must eat a fair few kitten biscuits.
I find even the purpose made tunnels don’t deter cats, you need as many angles as possible & as Nic said reduced height as a hog is very able to squish itself to get under, over or past awkward shapes whereas a cat isn’t quite so bendable because of their length. One entrance to my feeder has an inverted V shaped wooden tunnel the height of the doorway in the centre of the V (like a regular house roof shape) with 4 (2 end to end with 2 on top to form a wall) bricks directly opposite the open end of it leaving (about 3 & a half inches) no space for anything as big as a cat to enter, the other entrance is close to a resin shed & has an elaborate arrangement of screwed in place space reducing bits & bobs which the very fed up cat has finally admitted to being defeated by. It’s taken years & much head scratching to come up with the answer, but finally cracked it. Wile E. Coyote has nothing on cats!!
