Mallards in the snow

A pair of mallards showed up at the feeder, yesterday - the first day of spring. Today, they returned but with a few centimetres of snow. Lucky for them I had put out some birdseed an hour earlier so it was readily visible. I suspect this pair is the same pair that visited last year for several weeks. We've had a pair come by in the spring for at least five years now. They stay a few weeks an move on. Last year, they were around for five or six weeks.