> Crows weigh ~1kg and cigarette butts ~5mg, i.e. ingesting a single cigarette butt is 10 times what would send a human to hospital.
This assumes that humans and crows are physiologically identical, which they are not. Are the affected by tobacco in the same manner? How much do they end up injesting from the typical butt?
> This assumes that humans and crows are physiologically identical
I accept that this is partially relevant, but:
Since humans choose to consume tobacco, and animals including birds generally won't (hence tobacco plants are becoming invasive), if anything we should expect humans to have a higher tolerance and crows to have a relatively lower tolerance for tobacco products.
Is your point that it should be considered ethical until your questions have been exhausted? That isn't a good standard of ethics.
This assumes that humans and crows are physiologically identical, which they are not. Are the affected by tobacco in the same manner? How much do they end up injesting from the typical butt?