Tens of thousands of Minnesota anglers figure it's just been too cold to go fishing — or to even buy a fishing license.

Sales of fishing licenses through Monday are down by nearly 150,000 — or 37 percent — from the 10-year average. The Department of Natural Resources has sold about 258,000 licenses so far, easily the lowest total at this point in the season the past 10 years. The average over that decade is 407,000 licenses through the Monday after opening weekend.

"It's the weather, totally the weather," said Jenifer Wical, DNR fish and wildlife customer enhancement manager. Fishing license fees have been increased for 2013, but Wical said officials don't believe that is responsible for the lower sales.

"No one is in a mindset to fish [with the cold weather]," she said. Wical believes license sales will rebound if the weather improves. But many large northern lakes remained mostly ice-covered Tuesday, though officials are hopeful all but perhaps Lake of the Woods will be ice-free by the weekend. Ice went out on Crane Lake on Saturday.

The 150,000 lost license sales means big bucks to the DNR. An individual fishing license costs $22, so the agency is down about $3.3 million from last year.

Dayton lands walleye

Even many of those who bought fishing licenses didn't show up for the opener. Several conservation officers said it was the quietest opening weekend they've ever seen.

At Park Rapids, they had anglers, thanks to the Governor's Fishing Opener, which brought in about 300 attendees. And Dayton caught a walleye, something many anglers had difficulty doing. Dayton landed his in the Fish Hook River shortly after midnight Saturday. He and guide Jason Durham couldn't get on Fish Hook Lake because of ice.

Next year's Governor's Fishing Opener will be in the Brainerd Lakes Area, with headquarters at Grand View Lodge on Gull Lake.

Grass carp near Sartell

An angler bowfishing on the Mississippi River north of Sartell last week shot a 25-pound grass carp, an exotic species previously found only much farther south in Minnesota. Nick Frohnauer, DNR invasive fish/river habitat coordinator, said he believes the fish escaped from a private pond, or was released intentionally. It couldn't have come from southern Minnesota because it couldn't have gotten past the dams at Coon Rapids, St. Cloud and Sartell, he said. The fish was a female full of eggs, but Frohnauer doesn't believe there's a reproducing population. Grass carp eat aquatic plants, can grow to 70 pounds and can cause water quality problems.

Doug Smith • dsmith@startribune.com