I received this beautiful birdfeeder for Mother's day this year and I noticed the food was disappearing from it but I never saw any birds around it. Today I found out why!
What a shame. Maybe you need to come up with a solution to make the hole smaller which won't ruin the look of your pretty feeder. I had a mouse pinching my tomatoes over summer. Got him "on film" too. Still, it made for a great pic to share.