Well, from what I can tell, the sounds are not transmitted thru the air, but thru the ground, then thru the basements of the houses, then into the walls. I guess that this would be dependant on the type of wind generator, ground density, frequencies involved...etc etc.
As far as the birds and the bats, this problem has been documented throughout North America as a problem at many different sites, and again, may be dependant on flight patterns, density, species of local birds...etc.
Or maybe European birds and bats are just smarter than North American.