– Lake Mille Lacs walleye fishing could be shut down by early August, the Department of Natural Resources (DNR) said Tuesday, an unprecedented action on what historically has been the state’s most popular fishing lake.

The unexpected announcement shocked some Mille Lacs resort owners, who worried their businesses — already caught in a downdraft with the lake’s declining walleye population — would suffer.

Mille Lacs long has been a key driver in the state’s $2 billion fishing industry.

“I thought we had hit the bottom on this lake, but this is a new, lower bottom,” said Bill Eno, owner of Twin Pines Resort. “I’m in total shock. I never thought this would happen.”

DNR Commissioner Tom Landwehr said the lake’s walleye sport-fishing harvest quota likely would be exceeded by the end of July, forcing the agency’s hand. The quota is set as part of a Mille Lacs co-management agreement with eight Chippewa bands.

The DNR had calculated only a 20 percent chance existed that anglers would top their annual 28,600-pound walleye quota, the lowest in the lake’s history. But a combination of factors — driven primarily by the estimated number of walleyes that died in recent weeks after being released by anglers — conspired to undercut that prediction.

Now, despite the most restrictive walleye regulations in Mille Lacs history, anglers are only 3,000 pounds from topping the quota.

Fishing for northern pike, muskie, bass and other game fish can continue on the lake even if walleye fishing ends, the DNR said. Officials, however, acknowledged that interest in these species among Mille Lacs anglers remains low.

Fishing pressure rose about 20 percent this year during the first half of July, compared with 2014. Yet the number of walleyes harvested by anglers was nearly the same for the two years: 622 this year, compared with 612 in 2014.

The big difference was water temperature. In recent weeks it averaged almost 76 degrees, compared with about 71 degrees for the same period last year. As a result, the estimated hooking mortality— the number of walleyes that died after being released — was 6,257 the first two weeks of July, compared with just 776 during the same period in 2014. Hooking mortality is included in the harvest quota.

“The real problem is we have such a low harvest quota,” said Eric Jensen, DNR large lake specialist in Aitkin, noting that this year’s quota is 33 percent lower than in 2014. “The sport angler quota this year is just 28,600 pounds. Historically on Mille Lacs, if catch rates were good, you could hit that on a really good weekend.”

The eight Chippewa bands received 11,400 pounds of walleyes this year.

The 40,000-pound overall quota is at an all-time low because Mille Lacs walleye numbers are at or near a record low. Additionally, the DNR and the bands have changed the way the harvest quota is determined.

Biologists previously believed about 25 percent of walleyes 14 inches and longer could be harvested from Mille Lacs — a formula that helped establish a total harvest quota of 500,000 pounds as recently as 2012.

Now, because too few Mille Lacs walleyes have grown to maturity in recent years, managers set the harvest quota low enough to ensure spawning-age walleyes aren’t adversely affected.

In an attempt to keep anglers within their quota, officials this year slashed the walleye limit to one fish 19 to 21 inches long, or more than 28 inches. All others had to be released. Night fishing also was banned.

Resort owner John “Rockman” Odle said he urged the DNR to institute a catch-and-release policy this year for all walleye.

“I knew this was going to be the end result this year,” he said of the walleye fishery being shut down.

“It’s a sad thing, because this is the jewel,” Odle said, standing in his parking lot at the Rocky Reef Resort in Onamia, Minn. “Look out here!” he says, laughing as he waved at an empty Mille Lacs on Tuesday afternoon. “This is what it’s like on the weekend, too. It’s sad,” he said, adding that 50 or so boats would normally be bobbing on the waters within view of his resort.

The DNR’s next creel survey will end July 31, and Gov. Mark Dayton told the agency to wait until then to make a determination about closing Mille Lacs walleye fishing.

By then, DNR fisheries chief Don Pereira said, “We’ll likely be close to or over our allocation.”

It’s uncertain what will happen if the state exceeds its allocation. Pereira said the DNR has informed the bands of the possibility. Under a federal court ruling, the two parties negotiate harvest quotas and related issues. Unresolvable differences would be settled by the court.

“The state has shown a good-faith effort to stay within the allocation,” Pereira said.

If walleye fishing is stopped, no bait or lure restrictions for other species would be imposed. Walleyes would be incidentally caught while anglers fish for bass or northerns, and a percentage likely would die from hooking, Pereira said.

Meanwhile, operators of Mille Lacs group boats, or launches, say they’ll keep fishing.

“Looking for bass, we’re still going to be fishing where walleyes are,” said Eno of Twin Pines. “This time of year, all the fish are in the same areas.”

No discussions have been had about closing the lake entirely to prevent incidental catching of walleyes, Landwehr said.

Guide Tim Ajax said the fishery shutdown is “unacceptable.”

The government’s mismanagement of the fishery, and the treaty management of walleye during the spawning season, have lead to economic ruin for the region, in his opinion.

“We’re hanging on by a thread,” he said

The DNR has said the controversial spring walleye netting by Chippewa bands isn’t responsible for the decline in the Mille Lacs walleye fishery.

Sensitive to the economic hardships local businesses have suffered in recent years as the lake’s walleye population has fallen, Landwehr said anglers should fish Mille Lacs for other species.

“I want to encourage people to look at the special regulations we have on smallmouth bass and northern fishing,” he said.

Officials from the DNR, the Office of Tourism, and Department of Employment and Economic Development plan to meet with resort owners and other Mille Lacs stakeholders to discuss the situation and seek recommendations.

Said Landwehr, “This is a painful time we’re in.”