NOT KNOWN FACTUAL STATEMENTS ABOUT SWAN EGGS TO HATCH

I'm no skilled more info on swans. I relatively imagine that an evening-time predator filched the eggs. I have listened to men and women express that their birds( chickens, geese, whatsoever) get rid of infertile or nonviable eggs from their nest. In forty years I haven't experienced a chicken take out their own egg/s from the nest other than unint