i have pointers and used to raise pheasants. the dogs did not point those in the pen either. i believe this is because the dog has grown acustomed to the sent being there. it is kindof like the dog knows that the one free bird is out of place against the other smells and therefore points it. a dog knows what belongs where and when. they are smarter than we give 'em credit for. after all they lie around and sleep all day, we bring them food and water and clean up after them>