We have a small verandah at the second level of our house and it's seldomly used especially during winter. I had a look at it last weekend and the grills and walls were full of bird poo! I've cleaned it off thoroughly but just after a few days it's starting to build up again. What's the best way to keep the birds out? I was thinking of putting a cd mobile as that's what's recommended to keep the birds out of the veggie garden however I don't like the idea of hanging cds in front of our house. What esle can I do to keep the birds off?