When looking at Iowa waterways, it's easy to overlook the furrier creatures--otters, mink, muskrats, and of course, beavers.
"They are engineers, there's no question about it," says Jim Pease, wildlife expert.
Facilities management arborist at the University of Iowa, Andy Dahl, decided to take advantage of that engineering instinct.
"What they've actually done is help us open the vistas. They are almost the perfect employees," says Dahl. "They work the night shift, they don't call in sick; they're so efficient I'm afraid they may jump over me in the org chart."