So glad to hear you have able to locate him again. Something else to consider- regardless of if people are being discouraged to feed the birds there- with the colder weather many who use the area regularly may not be there as often either. With less to forage over the colder months- and less food provided by people many ducks - whether domestic or wild in lake and ponds do not fair so well through winter. Parasites could also be an issue in a wild flock.