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Sometimes ducklings fall between sewer or drainage grates as they are being led by the mother. The mallard adult will usually stay nearby because she is hearing the call of the ducklings. Call for help as soon as possible.
Once all ducklings have been rescued from this situation, they must be released together to be reunited with the mother
Waterfowl have defenses that may be harmful to people. Please do not try to capture these yourselves. Call WIN Emergency Response
Incidences with Waterfowl:
Call WIN Emergency Response of PA. as soon as possible. Have someone stay within sight of the animal to ensure it can be rescued and contained quickly.
When wood ducklings are interfered with, or trapped in a window well or have fallen through a storm grate, the mother ducking will fly away, sometimes returning when no one is visible to her. Call for help as soon as possible.
Once the young are rescued, they must be released together. The mother duck will wait till it is safe, then she will call the ducklings to her.
If a duckling is found by itself, sitting or left stranded in water (garden pond), and if known where the mother has taken the young, the flock can usually be found. Once they are located the lone duck can reintroduce. Do not stay to watch. Mother will not call until everyone is out of sight.
If the location of the mother and ducklings is not able to be found, call a rehabilitation center as soon as possible to have the duckling rehabilitated.
Because wood ducks and mergansers are cavity dwelling nesters, sometimes they are fly into chimneys and become stranded because they are unable to fly out. Usually the home owner notices a duck sitting on top of the chimney. This is usually an indication that its mate is inside.
Downy young goslings can be re-introduced shortly after separation. Be careful to ensure the gosling is reunited with family, otherwise it may not be brooded; and older and larger babies may kill it, or drive it away.
If one is not certain where the flock is, then the gosling will need to be taken to a wildlife rehabilitation center, where they can be raised properly.
Note that it is not that unusual to have goslings born in the winter especially where there is artificial light year round.