Anglers have surpassed the walleye quota on Mille Lacs Lake, fisheries managers announced Tuesday, but the season will stay open at the direction of Gov. Mark Dayton, who voiced concern about the impact a closure would have on the area’s economy.

The impact of continued fishing on the struggling walleye population should be “quite small” because the catch-and-release-only regulations, imposed for the first time this season, are successfully conserving the big 2013 class of walleye that will eventually spawn, said Don Pereira, fisheries chief for the Department of Natural Resources.

Mille Lacs’ total walleye harvest was capped at 40,000 pounds for this season, with 28,600 pounds allotted for state-licensed anglers and 11,400 pounds for Ojibwe bands with treaty rights on the big lake in east-central Minnesota. While sport anglers can’t keep any walleye this season, the estimated loss from hooking mortality — fish that die after being caught and released — must be counted against the state’s quota. Due to a surge in fishing and high catch rates in July, that number is approaching 38,000 pounds, Pereira said on a conference call.

The tribes, however, remain about 3,000 pounds below their quota. And tribal officials expressed disappointment with the state’s decision but declined to say whether they’ll take any legal action.

“The tribes upheld their agreement to stay within their set quota and they expected the state to do so as well,” said Dylan Jennings, spokesman for the Great Lakes Indian Fish and Wildlife Commission, which represents the bands with treaty rights on Mille Lacs. He added that several of the tribes voluntarily limited their walleye harvests further to protect the fishery.