The deadlines for removing fish houses and other portable shelters from Minnesota lakes are rapidly approaching. Shelters located south of Minnesota Highway 200 and US Highway 2 must be removed no later than midnight on Monday, March 5th. Shelters north of that line have until March 19th, with some exceptions. Anglers are advised to remove shelters early if ice conditions warrant. The mild winter weather has caused ice conditions to deteriorate rapidly across much of Minnesota. The DNR says a minimum of 4 inches of new, clear ice is necessary for ice fishing, and at least 5 inches is needed for snowmobile or ATV activity on the ice.