[thedufer]

> At the same time 3.5 billion birds die hitting glass of the buildings.

Do you have a citation for this? Are you comparing North American cat deaths to worldwide building collisions? Estimates I'm seeing of North American center around 600 million, a far cry from deaths due to cats.

[trhway]

It is in US:

https://www.nationalgeographic.com/premium/article/birds-win...

>a far cry from deaths due to cats.

No, they are about the same. The 3.5 billion is the top estimate similar to how 4 billion is top estimate for killed by cats. The lower estimates in both cases around 1 billion something.

[thedufer]

That's an interesting update. I remain a bit skeptical based on the fact that the obvious sources I'd look to for this sort of thing haven't updated on that study (it seems to be https://www.tandfonline.com/doi/full/10.1676/23-00045), and I'm not really able to evaluate it on my own. USFWS (https://www.fws.gov/story/threats-birds-collisions-buildings...) is citing the previous numbers, as is Wikipedia (https://en.wikipedia.org/wiki/Bird%E2%80%93window_collisions).

FWIW 3.5 billion is not the top estimate, although I'm not sure how to interpret the way the estimate is stated ("annual mortality may be minimally 1.28 billion–3.46 billion or as high as 1.92 billion–5.19 billion"). What does it mean to have a range for each end of the range? The author only quotes the absolute lowest number from the study in press about it (see https://www.lehighvalleynews.com/environment-science/3-5-mil...), but maybe is just preferring to be conservative.