"Under a grain hopper" ... You could put a few dozen pigeons, squirrels, around, and a pheasant or two, or even some wild turkeys, as they like to eat up all that spilled excess grain on top of railcar roof hatch's, and on the ground under the rail cars
In Canada, bears (as they are omnivores), deer, elk, and moose's (not to be confused with meece's) often forage piles of spilled grain, on, or near, railroad tracks.