The sun set Monday on a long-cherished tradition on Lake Mille Lacs.

In an unprecedented move, the Minnesota Department of Natural Resources shut down walleye fishing on the lake in an effort to protect what it says is a record low walleye population. By 10 p.m. Monday, dozens of anglers pulled their lines in, punctuating the first time walleye fishing closed midseason on the lake.

“It’s pretty sad,” said Steve Sandness of Albertville, who watched his fluorescent bobber toss in the waves Monday evening. Sandness was among a group fishing from a Twin Pines Resort launch on Mille Lacs.

He has made the hourlong drive to Mille Lacs about twice a week for 15 years to fish for walleye. “If I catch a bass, I’ll take a picture and throw it back,” he said. “I come for the walleye.”

He said he doubted he would travel back to Mille Lacs next week, figuring he will take his fishing elsewhere until walleye season reopens on the lake.

Just as he said that, Linda Eno, who owns Twin Pines in Garrison with her husband, came up behind Sandness and they hugged. It was a hug that was less about saying hello and more about saying goodbye to tradition. “He comes every Monday, and it’s Monday,” Eno said, her eyes welling with tears. “It’s been an emotional day. It’s just a tragedy.”

While about 20 people on the launch reveled in a nearly perfect summer evening on the lake, Eno looked out across a deserted expanse of water. “I don’t see a boat out there,” she said. “Ten years ago, there would have been 10 to 30 boats out there.” Anglers on this launch caught 46 walleyes, none of them keepers.

Just two hours from the Twin Cities, anglers headed to Mille Lacs for an evening or a weekend of fishing. Tourists from other states made it their getaway. During the boom years, when walleye were plentiful and restrictions were fewer, Eno said her resort business was closed only one day a year — Christmas Day. Now it’s closed a third of the year.

“The lake is out of balance,” she said. And each time walleye fishing became more restricted over the years, business owners believed things couldn’t get any worse. “What becomes tragic, then becomes the new normal,” Eno said.

Closing the walleye season in August will be the “final nail in the coffin for many businesses,” she said. The season normally closes the third week in February and reopens in early May, she explained.

Brent Peterson, who was fishing on the Twin Pines Resort launch Monday evening with his 10-year-old son, Wyatt, has fished Mille Lacs for nearly 30 years. He grew up in the area and now has a cabin on a nearby lake. He said he won’t be back to Mille Lacs until walleye fishing is open again. “We can fish for other fish on our lake,” he said.

Three years ago, the quota for Mille Lacs walleye was a half-million pounds. This year, it was 40,000 pounds. About two-thirds of that quota — or 28,600 pounds — was for sport fishermen; one-third was for the eight bands of Ojibwe tribes that have treaty rights to share fishing on the lake. Anglers this year have been limited to one walleye per person.

On Sunday, DNR officials said the sport fishermen’s allotment already has been exceeded by at least 2,000 pounds. So for now, walleye fishing on the lake is closed. Yet DNR officials stress that the smallmouth bass, northern pike and muskie fishing on the lake remains “outstanding.”

Terry Thurmer, owner of Terry’s Boat Harbor on the edge of the lake south of Garrison, just shakes his head.

“This was the No. 1 walleye lake in the state,” he said. It’s going to be tough to sell people to come here to fish bass, he said. “If this lake was in Alabama, that would be OK,” he said. “But we’re Up North and they come here for walleye. … After a life spent fishing walleye here, they’re not going to change.”

While anglers in search of Minnesota’s quintessential fish go elsewhere, he and other resort owners are going to try to survive.

DNR officials say something seems to be killing the young walleye. Predation by larger fish, including walleyes, too-high water temperatures, zebra mussels, spiny water fleas and invasive plant species all were mentioned as possible contributors.

But Thurmer, Eno and other resort owners argue that the DNR has mismanaged the lake, and they blame some of the problem on the tribes that are allowed to net fish during prime spawning season in the spring.

DNR officials disagree that the netting has affected the walleye population. Nonetheless, the Mille Lacs Band of Ojibwe, the largest band to fish the lake, said last week it would forgo its walleye harvest in 2016.

DNR officials will assess walleye numbers later in August and in September. If the numbers aren’t sufficient, 2016 could be a catch-and-release year, and the Ojibwe bands would do only ceremonial fishing, the officials said.

Eno holds out hope that walleye season will be open in time for ice fishing. January is the biggest month for her business, she said. “If they don’t open it, I’ll have to get another job. … To see such an amazing thing come to such a tragic end is hard.”