We found that out with our frog pond. But, I do have ideas for the bird bath.
#1 - I got a $1. fish net, like one uses in a fish tank, on Amazon, and Dh scoops the larvae off every couple of days.
#2 - In order for them to mature, they need 7+ days. So, if you clean it out every 5 or so days, they will never turn into mosquitoes. And, birds love the fresh water.
#3 - You can get a little bubbler, or other item that stirs up the water. They need water that's smooth to lay eggs, etc. And, again, birds come to the sound of water...they should love it.
#4 - There is a 'donut' that is supposedly not harmful to any critters but the bugs that it targets. It's one of the BT family; BTI I think.
I hope that one of these works for you!
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