Sorry I can't help with the duck. But here's a great thread on growing Rhubarb in Colorado. I grew up in Winter Park. My Grandmother had a huge planting of huge Rhubarb - it came back year after year and was delicious.
http://highaltituderhubarb.com/Growing_and_Harvesting_Rhubarb.aspx
http://highaltituderhubarb.com/Growing_and_Harvesting_Rhubarb.aspx