“Facts are stubborn things, but statistics are pliable,” Mark Twain wrote.
When the U.S. Fish and Wildlife Service recently released its national 2013 waterfowl hunting harvest report — based on a survey of hunters — there was an eye-popping number under Minnesota’s data. The estimated number of active duck hunters in the state fell from around 78,000 in 2012 to just over 52,000 last year, a precipitous 33 percent decline and the lowest total since the current survey method began in 1999.
The problem: No one believes that number is even close to accurate.
“I don’t think our hunter numbers dropped 30 percent because we still sold 90,000 state duck stamps last year,’’ said Steve Cordts, Department of Natural Resources waterfowl specialist.
And similar discrepancies in hunter number estimates turned up in Texas (down 38 percent), Missouri (down 28 percent), Louisiana (down 25 percent) and Arkansas (down 22 percent) — casting serous doubt about the accuracy of other data in the survey, including duck harvest estimates.
That’s a major problem because the survey, along with waterfowl population surveys and banding programs, is used by federal officials to set hunting season regulations nationwide.
“They did something wrong, and I don’t know what it is,’’ said Larry Reynolds, waterfowl biologist with the Louisiana Department of Wildlife and Fisheries. “There’s a reason why all of these states are having problems.’’
The federal report estimated the number of active duck hunters in Louisiana dropped from about 104,000 in 2012 to 78,000 last year, a decline of 26,000, which conflicts dramatically with state hunter surveys and state license sales. Other survey numbers are suspect, too, Reynolds said.
Khristi Wilkins, chief of harvest surveys for the U.S. Fish and Wildlife Service in Maryland, acknowledged that there appears to be a problem with the latest survey but said staffing issues make it uncertain whether the estimates can be corrected. In Minnesota’s case, there could be problems because of incomplete data or problems with survey responses, she said.
She noted all the figures in the survey are preliminary. When will they be finalized?
“I’m embarrassed to say we haven’t finalized anything since 2003,’’ she said. “That’s a really serious problem that I don’t have staff to deal with. We’re trying to do what we can, but we only have a couple of people.’’
Reynolds said that is a major concern.
“If the harvest survey efforts are struggling now because of lack of manpower, that’s something that absolutely has to be fixed,” he said. “Because we can’t even justify opening hunting seasons without credible estimates of harvest. That’s why HIP [Harvest Information Program] came into being in 1999, because of threats from anti-hunting factions that our harvest data was not credible.’’
The HIP program provides the Fish and Wildlife Service with a national registry of migratory bird hunters from which they can select participants for harvest surveys. Wilkins said the Fish and Wildlife Service is working with the Association of Fish and Wildlife Agencies and the four flyways to review and improve HIP.
The federal survey estimates the number of “active’’ duck hunters. Minnesota also surveys small game hunters to estimate the number of duck hunters and harvest, and looks at state duck stamp sales. Cordts said officials estimate that about 90 percent of the 90,000 stamp purchasers hunted last year.
That would equal about 81,000 duck hunters, but that figure doesn’t includes youths 17 and under, hunters over 64 or those hunting waterfowl on their own property — all of whom don’t need a state stamp to hunt.
In 2012, the DNR estimated there were about 90,000 duck hunters. The DNR’s 2013 survey results haven’t been completed yet. But Cordts believes duck hunter numbers here have been stable in recent years, after peaking at around 140,000 in the 1950s and ’60s.
The federal estimate of active duck hunters is important because it affects other data in the report, including duck harvest. The report estimated Minnesota hunters killed about 608,000 ducks last fall, 141,000 (19 percent) fewer than 2012.
Cordts doubts that number, too.
“I don’t think the harvest is actually down that much, because I don’t think hunter numbers declined,’’ he said. “It seemed like a pretty good season, from what we heard. All of our indications are that it was similar to the year before.’’
And if the federal hunter numbers had been the same as last year, the federal harvest figure would have exceeded last year’s, Cordts said.
While the three methods of estimating the number of Minnesota duck hunters all produce different results, generally they track one another.
“This year the federal number is an outlier,’’ Cordts said. “There’s no way to really explain it.’’
Meanwhile, the federal survey showed Wisconsin had about 53,000 active duck hunters, slightly more than Minnesota. But Kent Van Horn, Wisconsin DNR waterfowl biologist, said his eyebrows raised last year when the federal survey showed an 18 percent drop in duck hunters there.
“I said that doesn’t make sense,’’ Van Horn said. “For several years, the trends [in the federal survey] were consistent with the data we collected. But all of a sudden there was this drop in hunter numbers.’’