We have an Indian Minor problem locally, they would spread dog food everywhere, crap on the patio, crap on the outdoor furniture and also on the clean washing on the clothesline. I designed a simple
feeder which no bird can access. It also protects dry food from ants, snails or slugs and even cockroaches. I have been using it for at least ten years. I had a provisional patent on it but have never pursued selling or manufacturing.