By placing old tennis balls on your patio or porch, will they keep birds away???
I've never heard of tennis balls scaring birds away. Interesting concept.
Don't know why you'd want to scare birds away? We garden for wildlife and buy a lot of bird food to attract them. It's our favorite entertainment.
Maybe what you're trying to do is to keep the birds from hitting the glass patio door? Here's an article on Preventing Bird Collisions With Glass.
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