The parents do teach the young how to fly. There may be something that has caused the young swan not to fly: Injury or illness, stunted growth, or just not old enough to fly on its own yet.

From your description, it sounds as if this is a lone juvenile that was chased from its habitat and found your pond. The defensive swan may have been the actual "owner" of the pond and did not want the new intruder on his pond. If this was the parent swan, it was the parent's way of saying that it is time for him to find his way, choose a mate and establish his own habitat.

In any case, the orphan should move on once the weather starts to turn inclement and it will go onto the migratory path for the winter. If it does not leave and the pond freezes, then the cygnet could be attacked by a predator which can walk across a frozen pond, drown, starve, become dehydrated, stressed and suffer from injury or illness. The problem with intervening is that Michigan DNR wants to kill all the Mute Swans in Michigan in order to open habitats so that they can introduce the larger Trumpeter Swans for Trophy Waterfowl hunting purposes.

So, you may not be able to intervene as it will definitely cause the demise of the cygnet (at the hands of the Michigan DNR or a veterinarian/wildlife rehabber who are required by the DNR to kill any Mute Swan brought to them). We hope that this situation is solved naturally and the swan leaves on its own. If the parents do return in the spring, we would suggest that you remain on guard, especially at night as this is when the Michigan DNR officials attack nests, kill the adults and cygnets. The Regal Swan