The subtitle is revealing:<p>[We don't know how much birds kill the windmills so] "This makes it a weak argument against windmills"<p>"We don't know how much, so it may not happen, or is not so relevant as we think, but is repeated by ideology", is a nasty trick. Nice smoke curtain. Specially when is joined later with:<p>"it is true that all humanmade structures are technically bird killers, but..."<p>Either it happens, or it does not happen.<p>We aren't talking here about a sparrow crashing against a window. What we do know is that carcasses of big raptors, vultures, storks, other birds, and even bats can be found near the windmills basis often, in a distribution that is not aleatory.<p>Even if we never achieve to calculate an exact value (before the corpses are quietly removed by foxes or companies) we can identify that there is a problem here. As predators are scarce (by definition) and some are endangered, the impact on populations is not negligible.<p>Killing endangered species is illegal. It does not matter If is "just one" or "just a few" eagles.