Wildlife crossing
Wildlife crossings are structures that allow animals to cross human-made barriers safely. Wildlife crossings may include underpass tunnels or wildlife tunnels, viaducts, and overpasses or green bridges (mainly for large or herd-type animals); amphibian and reptile tunnels; fish ladders; canopy bridges (especially for monkeys and squirrels); tunnels and culverts (for small mammals such as otters, hedgehogs, and badgers); and green roofs (for butterflies and birds).