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(Image Credit: Image 1 | Image 2 )
Roads can cause major problems for wildlife, and not just from the danger of being truck by vehicles. With busy enough traffic, wildlife may avoid crossing at all, causing habitat fragmentation. In order to stitch habitats back together, wildlife overpasses, underpasses/tunnels, and viaducts are all used.
Typically, overpasses work better than underpasses for most wildlife, since not all wildlife is comfortable traversing into a dark (sometimes loud with traffic vibrations) tunnel. In comparison, the overpasses are typically made to feel like a hill for wildlife; with soil, grass, and trees added.
No matter what people build, however, it can help.
(Image Credit: Image 1 | Image 2)
In most cases, the cost of building and maintaining these crossings end up being less than the cost of repairs, injuries, and cleanup that occurs when a vehicle strikes an animal.
