Why did the duck cross under the road

[zak]

to avoid the street danger ,many species are crossing the road using a tunnel under it.
http://a7.sphotos.ak.fbcdn.net/hphotos-ak-snc7/s720x720/379401_145815112186642_134978456603641_165509_1954162554_n.jpg

http://www.facebook.com/media/set/?set=a.145815092186644.22530.134978456603641&type=3


http://www.umces.edu/al/project/new-study-uncovers-how-animals-maryland-use-underground-highway-culverts