Normally, the bird cages are along the walls. It's a fairly sizable room so the nearest cage is about 15 feet from the french doors, so the cat's don't really notice the birds and vice versa. (And during free fly, I put a sheet up over the doors to avoid flying into the glass accidents.)
But I had to move them off the walls so we could put up new cages and shelves and so forth.
One cage is right up against the french doors, so I put up rice paper to serve as a visual divider so the cats couldn't see the birds and vice versa.
The birdies don't need that stress! I explained it to my husband as being akin to having a guy sitting outside your window 24/7, with a shotgun pointed at your head. Nobody wants to feel hunted. It's stressful!
I'd just finished putting up the rice paper and I came out to a line-up of 8 cats, all staring at the french doors.
So I stepped outside so I could see what they saw:
It's like a giant shadow box!
And it's driving the cats crazy!
But it works nicely.
Fortunately, it's darker outside of the bird room and there's no backlighting, so the birds don't see the cats' shadow. They're happy as clams and have no idea there's pack of cats lurking mere inches away, so mission accomplished.
It's rather funny, though with the cats.
It's been up for about 36 hours now and there's always at least a couple cats sitting in front of the door, rapt attention!
