DULUTH, Minn. — Minnesota duck hunters once had a love affair with scaup, often called bluebills, a duck that nests up by the Arctic Circle and made its way through the North Star state late each autumn, buzzing decoys on big lakes across the Northland.
But starting in the 1990s, the number of bluebills flying over Minnesota was getting noticeably smaller, and since then it's just kept going down.
Throughout the 1930s and '40s and even '50s, scaup were the most common, most numerous duck shot by Minnesota hunters, more than even mallards. Now, they are 12th on the bag list.
At one point a century ago, Minnesota hunters were shooting more than 750,000 scaup per year. Now, it's fewer than 10,000.
"We shoot more hooded mergansers now in Minnesota than we do scaup, which is kind of interesting but also kind of embarrassing," said Steve Cordts, waterfowl biologist for the Minnesota Department of Natural Resources stationed in Bemidji.
Cordts said there are two major issues in the decline of bluebills in Minnesota. Their overall numbers in North America are down as female scaup don't seem to be surviving or reproducing well. The continent-wide population is down 50%, from more than 7 million in the 1980s to about 3.6 million today.
Biologists speculate that parasites may be an issue, as may contaminants, such as selenium. (Minnesota experienced several major scaup die-offs in recent years from acute infestations of intestinal parasites called trematodes, which are carried by faucet snails that the ducks eat in some lakes.) Nutrition and habitat disturbances also are on the list.
But there still are millions of scaup, both lesser and greater varieties, flying south every fall. They just don't seem to be flying over Minnesota any more.
There's some indication many scaup are migrating farther west on their way from northern Alaska and Canada nesting sites to their wintering grounds off the Carolina and Louisiana coasts. Many bluebills are now seen on Devils Lake in North Dakota, for example, where they were not reported 50 years ago.
"There's also some sign they are skipping us to go east, over to Lake Erie," Cordts said.
But because so few hunters outside of Minnesota and Wisconsin and the Carolinas bother to hunt bluebills, there isn't much interest in researching them. Every state wants mallards, and more charismatic species like pintails get lots of scientific attention.
"'There just isn't as much interest, outside of a few states, in scaup. ... And because they nest so far north, it's really hard to study them on their nesting grounds, which makes it hard to figure out what's going on," Cordts said. "Even up here, we are losing our scaup hunters because the bag limit is so low. Not many people bother to hunt them any more."
With a bag limit of one scaup daily early in the season and two later, not many Minnesota hunters will spend hours setting up the dozens of decoys needed to attract them in, especially during cold, late-season conditions on big lakes.
At one time, bluebills were common across much of the state late in the season. Even 30 years ago, huge rafts of thousands of scaup could be found on Lake of the Woods, Winnibigoshish, Leech and other big lakes in northern Minnesota. Not anymore.
"It's down to a few places, Thief Lake, Bowstring and some of the pools on the Mississippi in the southeast," he said. "Other than that, scaup are almost nonexistent in Minnesota. And we really don't know why that happened."
There's speculation by some that Minnesota lakes have lost key elements of their aquatic plant and animal communities, aquatic invertebrates such as mollusks, insects and crustaceans and also aquatic plants and seeds that scaup eat.
Alan Afton, noted waterfowl biologist and adjunct professor at Louisiana State University who has researched scaup extensively, called Minnesota's scaup decline "a complicated story" that probably centers around a decline in good food in Minnesota lakes, forcing the ducks to change their migration routes.
"Of course, scaup are less abundant now than they were historically. The most important factor, in my opinion, is that preferred foods, such as amphipods, are much less abundant now as compared to what they were historically in Minnesota, for a variety of reasons," said Afton, who lives near Bemidji. "Availability of preferred foods is better to the west of Minnesota and migrating scaup have responded to greater food availability in other areas outside Minnesota."
Others say an increase in fall boat activity on Minnesota lakes may scare scaup off. Yet another theory is that scaup are passing through much later than decades past due to climate change, well after most duck hunters have quit for the season. (There are also far fewer duck hunters in the state, about 75,000 now, half of the number 50 years ago, so far fewer people are out looking for them at all.)
The most popular duck for Minnesota hunters now is the mallard. But their numbers have been down a bit in Minnesota as well, and Cordts said he sees a day when wood ducks will become the most commonly taken bird by hunters in the state.
Last year in Minnesota, hunters shot about 84,000 of each species.
"Wood ducks are now No. 2, but they are within a few hundred of catching mallards," Cordts said. "I still think that will happen soon because wood ducks seem to keep doing very well here."
Cordts said most Minnesota duck hunters will have far better access to lakes, streams and swamps for the Sept. 24 opener thanks to ample rainfall across most of the state, especially in the north.
Last year at this time, a severe drought kept hunters away from some of their favorite areas — the water was simply too shallow or entirely absent.
"Up north, access should be very good. The one exception in the state is a dry area from near the metro area west to the South Dakota border where it's been pretty dry," Cordts said.
Both duck and goose production was likely down this year in Minnesota because of the cold, late spring that led to later nesting and poor nesting success. Canada goose numbers are generally down across the state, as was reflected in generally poor reports during the early September goose season, Cordts said. While many wild bird re-nest if their entire brood succumbs to bad weather or predators, the second effort usually produces fewer chicks.
"The reports we had from the early teal season were pretty good, with quite a few teal around," he said. "But I just don't think we produced a lot of geese this spring due to the weather."
The cold, late spring also impacted wild rice production, with rice maturing far later in the season and generally less rice than recent years. Cordts said Northeastern Minnesota's Arrowhead appears to have better wild rice than other areas.
"It's been a pretty poor year for most wild rice harvesters. The rice was short and still green when they wanted to go out," Cordts said. "But that can be better for duck hunters because it means thinner rice that they can get through. And there is still enough for the ducks to stop and eat."
Cordts said parts of Canada and North Dakota appear to have better nesting success this year, which could forecast a good northern flight of some species through Minnesota later in the season.
— The duck season across Minnesota starts a half-hour before sunrise Sept. 24. In the north, it runs continuously to Nov. 22. In central and south areas, it closes from Oct. 3-7 and then reopens Oct. 8 to Nov. 27.
— The daily limit is six ducks, of which no more than four can be mallards (two hens maximum.) The daily limit for other species include wood duck, 3; redheads and canvasbacks, 2; black ducks, 2; pintail, 1; scaup, 1 daily through Oct. 13 and 2 daily after; teal, 6; ring-necked ducks, 6; all other species, 6.
— The goose season in northern Minnesota runs Sept. 24 to Dec. 23 with a limit of five daily statewide. In central and southern zones, the season starts Sept. 24, closes Oct. 2-7 and then reopens Oct. 8 to Dec. 28.
— Possession limit is three times the daily limit (but only starting three days after the season begins.)
— In addition to the early September teal season, rule changes that started in 2021 continue this year, including hunting allowed until sunset all season with no 4 p.m. closures and use of spinning wing decoys and remote controls allowed all season.
"And when a flock of bluebills, pitching pondward, tears the dark silk of heaven in one long rending nose-dive, you catch your breath at the sound, but there is nothing to see except stars. This same performance, in daytime, would have to be looked at, shot at, missed, and then hurriedly fitted with an alibi."
— Aldo Leopold in "Sand County Almanac"
"Have you thus sat on a snowy day and squinted through the white curtain at those mail-carrying bluebills? Until you have courted bluebills in the snow, you have not tasted of the purer delights of waterfowling. Fat mallards over a sunny marsh are fine. Planing, twisting teal in early-season days are sporty. There is pleasure of many sorts in the harvest of autumn over the ducking grounds. But the Old Duck Hunters are extremely partial to the bitter last days, those stormy days when the wild, free things of duck shooting are abroad in the very wind with the storm."
— Gordon MacQuarrie in "Stories of the Old Duck Hunters"
