ALEXANDRIA — As Minnesotans get ready to celebrate one of the most special days in our calendar, the opening of fishing season, there’s one thing that birders and others want to remind us about: Dispose of monofilament line safely, appropriately, and not in the lake or on the shore. “Monofilament line is used for fishing,” says Amy Westmark, “and if not disposed of properly — left on the shoreline or left in the lake — it can pose a risk to wate…