Mallard with Snail, 7/25/16, Fisk Pond

At Fisk Pond I saw a mallard with a large freshwater snail stuck in the back of its mouth. The duck seemed to be in distress, its tongue was sticking out and it was shaking its head trying to dislodge the snail. Eventually it came loose, I don't know if it went in or out but the duck was fine a minute later.