That seems like a very high bound. Another source says there are 7.2B birds in US and canada[1], so 1B birds would be 14% of all birds, which is really high. I also feel like 7.2B dead birds would be very noticeable in the form of dead birds on sidewalks, which I'm not seeing.
It might surprise you, but buildings in places other than the US and Canada now have windows too. By some estimates 95% of the world's windows are outside of US/CA!
(Not that it matters, birds are a pretext, nobody really cares about birds, otherwise outdoor cats as pets would not be a thing.)
The source linked in the parent post says the 1 billion figure is for US only. Maybe the number is more plausible if it's applied worldwide, but the source should be considered as unreliable.
Shouldn't this be scaled to the drastic difference in proportion? I'm willing to accept the hypothesis that turbines are no more dangerous (or even less dangerous) than windows, but with raw numbers it feels like we're comparing apples and oranges. I don't have accurate counts for the number of windows globally, but I'm fairly confident it's much higher than the number of wind turbines.
I do not understand why solar fields do not take the ample roof areas. That is usually just wasted, even worse the roofs are mostly of some dark color where I live, they heat up the area for no good reason at all.
That's true, but a non-trivial factor driving down the cost of solar electricity is not only the panels themselves, but economy of scale in all the rest, like electrical systems to connect them to the grid, support structures for the panels, installation and maintenance, etc. etc. So rooftop solar, while attractive from the perspective of not industrializing the wilderness, is more expensive than utility-scale solar.
But yes, it would be nice with building codes requiring to either have solar or green roofs. That would certainly help drive down costs, and in the case of green roofs, reduce cooling demands as well as providing (depending on what you plant, granted) a haven for biodiversity.
The main impediment to roof-top solar is actually the roof tops themselves. Most were not constructed with the weight of solar panels in mind, nor are all roofs built to a common standard. Thus every roof needs an expensive inspection to see if it can have solar panels mounted as-is, and if not you also need an expensive custom plan to reinforce the roof.
Also the grid is really not designed for large amounts of decentralized power generation. While modifying the grid is probably easier than replacing roofs en masse, it's still expensive. Dedicated solar plants can take advantage of economies of scale.
The amount of birds killed by wind turbines is non-zero but negligible (Negative per W/Hr if we count oil spills) Solar fields do disrupt habitats, but less so then other commercial uses of the same land.
Dams have a species eradicating impact on Salmonoids. There would be no Salmon left on the west-coast if we didn't specifically breed and plant them.
> The amount of birds killed by wind turbines is non-zero but negligible.
Wind turbines don't equally affect all species. Raptors are much more vulnerable to them than are other birds in the area.
When raptors are hunting they are looking down to spot prey, and they have an eye ridge and feathers that try to block out other directions (to keep the sun out so as to not interfere with spotting small prey down below). This means that they have trouble seeing what is in front of them, reducing their chances of noticing that they are going to fly right into something.
Some wind farms are trying to address this by having spotters that keep a watch and when they see a raptor approaching shut down the section of the wind farm the bird is hunting in.
There's a company that has a system for automating this, using cameras and computer vision software to spot the approaching raptors [1].
[1] https://www.fws.gov/birds/bird-enthusiasts/threats-to-birds/....
[2] https://audubonportland.org/our-work/rehabilitate-wildlife/b....