Breeding Ducks Down Slightly Overall Populations Good
North America's spring duck population decreased by about 6 percent in 2019, but most species remain higher than long-term averages, and Delta Waterfowl said there's plenty of other good news for waterfowlers.
Waterfowl Population Status, 2019, released Monday, and based on surveys conducted by the U.S. Fish and Wildlife Service and Canadian Wildlife Service, estimated the breeding duck population at about 38.90 million, down from the 2018 estimate of 41.19 million but still 10 percent higher than the long-term average.
The surveys have been conducted annually since 1955. The 2019 initiative marked the fourth consecutive year the spring duck population has declined and the lowest total breeding duck population estimate since 2008, the last time that estimate was lower than 40 million.
“The fact that the numbers are down is a reflection of last year’s dry conditions for nesting ducks,” Dr. Frank Rohwer, president and chief scientist of Delta Waterfowl, said in a press release. “We know that production drives duck populations, so it’s no surprise that after a year of poor production, the USFWS counted fewer ducks.”
Gadwall numbers showed the highest growth, increasing about 13 percent to 3.26 million, which is about 61 percent higher than their long-term average. Mallards were up about 2 percent at 9.42 million, or about 19 percent higher than their long-term average. Green-winged teal increased about 4 percent to 3.18 million, which is 47 percent higher than their long-term average. American wigeon essentially held steady at 2.83 million and remain 8 percent higher than their long-term average.
“The real surprise to me is that gadwalls seem to be almost drought-proof,” Rohwer said. “They’re pretty amazing ducks.”
Blue-winged teal displayed the largest decrease in puddle ducks, dropping about 16 percent to 5.43 million but remaining about 6 percent higher than their long-term average. Northern shovelers decreased about 13 percent to 3.65 million but were about 39 percent higher than their long-term average. Pintails were down about 4 percent at 2.27 million and remain about 40 percent lower than their long-term average.
“The bluewing estimate makes sense,” Rohwer said. “Bluewings didn’t fare well last spring given the dry prairies and didn’t produce many ducks. Many pintails settled in the Dakotas seeking better water conditions, as did all ducks. But the core of the pintail’s traditional breeding range is in southern Alberta, where they’re down 79 percent, and southern Saskatchewan, where they’re down 85 percent. More than a million pintails — almost half the breeding population — settled in the U.S. prairie this year.”
For divers, redheads decreased about 27 percent to about 730,000 but remain at their long-term average. Canvasbacks decreased about 5 percent to about 650,000 but are about 10 percent higher than their long-term average. Scaup declined about 10 percent to 3.59 million, which is about 28 percent lower than their long-term average.
“I’m concerned that bluebills may return to restrictive harvest regulations if their recent population trend isn’t reversed,” Rohwer said. “And we’ve been living off high redhead numbers for a long time, but we just had two average to dry years.”
May pond counts decreased about 5 percent overall and 5 percent lower than the long-term average, but that varied by region. In the north-central United States (Montana and the Dakotas), pond counts were up about 36 percent. However, prairie and parkland Canada — Alberta, Saskatchewan and Manitoba — were dry, and ponds decreased by about 22 percent.
“This year’s pond count and nesting conditions are truly a tale of two countries,” Rohwer said. “Canada is in bad shape — it started dry and got even drier. I haven’t seen portions of Canada this dry since the mid-1980s. However, the prairies in the Dakotas started wet and stayed ridiculously wet. The problem is that while many of the duck estimates in the U.S. are up, it wasn’t enough to compensate for dry conditions in a region as massive and important to ducks as prairie Canada.”
But Rohwer said production in the wet eastern Dakotas has been exceptional. Mallards in that region increased 54 percent, pintails jumped 64 percent, bluewings rose 19 percent and total ducks were up 29 percent. That’s good news for hunters, whose relative annual success is determined by the fall flight, not the breeding population.
“The numbers aren’t as bad as they appear,” he said. “For example, even though bluewings are down, a higher portion of their breeding population than average settled in the wet Dakotas, where they should produce ducklings like crazy.”
Prairies in the United States were very wet from south to north, which should lead to strong duck production, Rohwer said. Conditions remained wet and actually improved during the breeding season, with temporary and seasonal wetlands retaining water into July and August.
“So when the prairies were dry last year, it hurt duck production and, in turn, duck hunters,” he said. “We saw it in Louisiana and elsewhere. But this year, ducks nested and renested in the U.S. prairies with a vengeance and should have high brood survival in those landscapes.”
Strong production in the American prairies should increase the number of juveniles, which typically decoy more easily compared to adult birds.
“There will be plenty of ducks in the fall flight, and I expect duck hunters — especially in the southern U.S. — to have a better season this year,” Rohwer said.