Check this site out as most domestic ducks are bred from mallards. These are flightless and would stay year round. They would also cross breed with wild mallards producing all sorts of mixtures. Pay special attention to the Rouen (which looks like a Mallard) and the Blue Swedish which sounds like your original weirdling. Kevin
http://www.domesticducks.co.uk/<http://www.domesticducks.co.uk/>
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