Sustaining Mille Lacs Smallmouths While Rebuilding Walleye Fishery a Tough Challenge for Minnesota DNR
Maintaining a single world-class fishery in a lake is one of the greatest challenges for a state wildlife agency. As they employ and/or alter regulations, resource managers must consider constantly changing biological and environmental variables, as well as possible economic and social impacts.
And when a lake has two world-class fisheries and one of them is in decline . . .
"It's a complicated mess," said Eric Jensen, a large lake biologist for the Minnesota Department of Natural Resources (DNR).
That's the situation that DNR finds itself in at Mille Lacs Lake, site of the Toyota Bassmaster Angler of the Year Championship Sept. 15-18. With a five-fish bag of 25 pounds not uncommon, the smallmouth fishery arguably is more robust than ever, earning a No. 10 ranking among the best bass lakes in the nation by Bassmaster Magazine in 2015.
On the flip side, the once productive walleye fishery is in steep decline. In fact it's so steep that the agency finally went all the way and imposed a ban on harvest in 2016, and prohibited the use of live bait, except on launch (party) boats.
At the same time it's been imposing tighter and tighter restrictions on walleye harvest in recent years, it's been allowing increased harvest of smallmouth bass. In 2013, the limit went from one fish to six. This year's it's four.
But Jensen's comment was not intended to suggest that DNR doesn't have sound science to back these decisions. Rather it reflects that management regarding such popular, productive, and economically important fisheries is controversial, as they impact diverse constituencies.
How so? Many walleye anglers want to keep and eat their catch, while most bass anglers catch and release, with no thought given to harvest. But for 2016, at least, meat fishermen can't keep their preferred species. Yet they can take home bass.
As a consequence, bass anglers fear irreparable harm to the smallmouth population. Concurrently, many resorts and other businesses around the lake fear the ban on walleye harvest will do damage local economies, as anglers go elsewhere, where they can keep the fish that they prefer to target.
While a state legislator introduced an ill-fated bill to negate the ban on walleye harvest, the Minnesota B.A.S.S. Nation (MBN) joined forces with the newly formed Mille Lacs Smallmouth Bass Alliance (MLSBA) to launch an awareness campaign about the importance of catch and release for sustaining the lake as a world-class bass fishery. They intend to post signs at private ramps around the 132,000-acre lake.
"We want to educate fishermen and businesses too that catch and release, not catch and kill, is the way to go," said Mickey Goetting, conservation director of the MBN, which has started a GoFundMe page to raise $2,750 for the effort.
MBN posted this message on the page: "Smallmouth have become the target as a replacement for walleye table fare. Minnesota B.A.S.S. Nation is concerned that increased fishing pressure and a substantial increase in harvest could adversely impact the world-class Mille Lacs smallmouth bass fishery. Smallmouth bass grow very slowly and we need to protect them."
DNR, however, steadfastly maintains that is not sacrificing bass or trying to reduce bass populations to reduce predation on walleye. Rather, its intent is to "provide alternate harvest opportunities, preserve quality sizes, and maintain quality catch rates."
Last fall's gill net survey "showed the highest catch we've ever seen (for smallmouth bass)," Jensen said. "Since 1998, the trend has been steadily upward."
Additionally, 74,150 smallmouth bass were released in 2015, while only an estimated 5,000 were harvested. "Not everyone is keeping bass," he added.
Sadly, the walleye population has been declining for nearly a decade. Causes are uncertain, but potential causes could be the same ones contributing to increasing numbers of hefty bronzebacks. "A lot has been going on at the same time," the biologist said.
That includes increasing water clarity, which benefits bass, primarily sight feeders. Walleye prefer darker conditions. Also, clearer water means less productivity in the form of phytoplankton and zooplankton at the bottom of the food chain for prey fish to eat. "Walleye eat mostly fish, and there's not as many fish," Jensen explained. "Smallmouth also eat crayfish."
With warming water possibly contributing, these changes began even before the introduction of invasive zebra mussels and spiny water fleas. But they seem to have accelerated as the exotics proliferated, gobbling up zooplankton and filtering out much of the lake's energy.
In a nutshell, not enough young walleye have been surviving to maturity and replenishing the population since at least 2008, with numbers being at a 40-year low in 2015. But hope is on the horizon, thanks to a strong year class in 2013, which DNR wants to protect via the ban on harvest.
"As walleye get to 14 inches, they are more desirable and that 2013 class is moving into that size now," Jensen said. "It's strong and it looks like it's going to contribute to spawning biomass. Females grow much larger than males and, in another couple of years, they will really start to contribute."
But bass anglers fear what will happen, as meat fishermen turn their focus to the smallmouth population while walleyes slowly recovers.
"This is a very special fishery with national significance to bass anglers everywhere," said Jim DaRosa, president of the alliance. "Mille Lacs needs to be protected. It may take several years to restore walleye to the levels they once were. We want to be proactive and make sure the smallmouth are healthy and sustainable while the walleye population is being restored."
Bass Regulations History for Mille Lacs
Before 2000: 6 fish, smallmouth and largemouth bass.
2000: 1 fish, 21 inches minimum length.
2013: 6 fish, with one longer than 20 inches. Protected slot of 17 to 20 inches.
2014: 6 fish, with one longer than 18 inches. Season opens with walleye. No fall catch-and-release restriction.
2016 Regulations for Bass, Walleye, Northern Pike
Bass: 4 fish, with one longer than 21 inches. All bass between 17 and 21 inches must be released immediately.
Walleye: From May 14 to Dec. 1, anglers targeting walleye must use artificial bait and immediately release all walleye caught. Night closure beginning May 16, from 10 p.m. to 6 a.m., and continuing through Dec. 1.
Northern Pike: 5 fish with only one longer than 40 inches. all pike 30 to 40 inches long must be immediately released.