When reading this question (What is the ecological justification (if any) for bird feeders?) on bird feeders I wondered if there would be an ecological impact on having a bird bath.
Especially in cities where summer temperatures can be a bit unforgiving (and the fact that we've replaced natural landscapes with concrete) it may seem like installing a bird-bath in your yard will aid birds in dealing with the temperatures.
So far it seems like a good idea. But is there be a downside I might be missing?