Waterfowl, especially swans do not do well with leg fractures. If the swan is swimming and is able to get up and down the bank easily, then it may do well as it may not be a complete fracture. However, if you can see bone sticking out, the leg hanging, swan not being able to move, then it needs to be captured and taken to a veterinarian immediately so it does not suffer. There is also a possibility that the swan was attacked by a predator if there is a lot of blood, i. e., snapping or soft-shelled turtle, otter, mink, alligator, bobcat, dog, etc. In any case, the swan is not going to survive without an exam and possible treatment. The Regal Swan