Regarding animal bridges here: yes, they are common along newer highways and railways. Mostly in mountainous areas, but for example the Budapest-Vienna highway in the border region (which is flat or has low hills, wind power plant country) must have about a dozen, mostly for rabbits (but I have cycled over one). Here is a link to a page with two webcams looking at the construction of a railway gallery [= open-to-one-side tunnel] along a line doubling in Austria; on the second you'll notice the outer "bridgehead" of what will be a rather wide animal bridge over the old line.
On your continent, they must exist at least in Canada too: I think I saw a photograph of one in, what must have it been, a National Geographic article on Banff national park? *Lunatic*, n. One whose delusions are out of fashion.
This is a lovely area and there's quite a lot of nature here. In fact, I'm so enthusiastic about it that when my friends visit I tend to bore them with listing all the fine qualities. The Chamber of Commerce should be paying me.
The proposed animal bridge in my comment is also in the mountains -- over Interstate 90 through the Cascade range. Maybe we can eventually make language a complete impediment to understanding. -Hobbes
