Was The Fall Flight of 1999 Really An All-Time Record?

By Dan Nelson
Delta Waterfowl Magazine Editor

I’ve been hobnobbing with wildlife scientists for more than three decades and have enjoyed every enlightening conversation.

I’m fascinated by the way scientists think. They take nothing at face value, accept no premise without proof. Science is the search for truth, and the biologists I’ve known have been relentless in its pursuit.

When my early discussions with fisheries and wildlife biologists turned into debates, I often made the mistake of propping up my arguments with “anecdotal evidence”, an observation based on a random event—“We had great duck hunting this morning, therefore the duck population must be soaring.”

Anyone who spends much time with scientists quickly learns to keep his anecdotal observations to himself. These folks deal strictly in proven, published, peer-reviewed scientific data.

All of which explains why I was stunned when some conservation leaders made the decidedly unscientifc claim that the 1999 fall flight of ducks was “an all-time record”.

Really? Based on what? Who counted the ducks that migrated across the continent in 1999? In what library did someone unearth the research paper that revealed the results of a duck census conducted in the 1880s?

I waited for the scientific community to howl in protest, to say that comparing the fall flights of the ‘90s to those of the 1950s or the turn of the last century or at any other point in history is an apples-and-oranges effort in futility.

I’m still waiting.

Calling ’99 an all-time record fall flight is like saying Joe Louis would have whipped Muhammad Ali. It makes for an interesting late-night discussion, but there’s no way to prove it.

On the other hand, what’s wrong with a little innocent hyperbole? Aren’t we journalists guilty of spicing up our reporting once in a while to hold our readers’ attention?

Perhaps.

But the wildlife scientists I’ve known don’t deal in fish stories.

Calling the fall flight of 1999 an all-time record goes against the grain of everything we know about duck production, as award-winning outdoor communicator Tony Dean aptly pointed out when he said, “We’re always being told that habitat is the key to healthy duck populations, but everyone knows there was a lot more habitat—more grass and more wetlands—in the 1950s than the 1990s. The idea that less habitat produced more ducks flies in the face of science.”

Indeed. And therein lies the problem. The conservation community doesn’t seem to be listening to the science, and that doesn’t bode well for the future of ducks.

Can You Hear Me? Can You Hear Me Now?

The waterfowl conservation movement was born in response to the great drought of the 1930s. When wetlands across the northern breeding grounds turned to dust, sportsmen set out to “drought-proof” the prairies by creating and restoring wetlands that would always be available for nesting ducks.

Hunters threw their support behind conservation organizations and purchased federal duck stamps, secure in the knowledge that their dollars were being put to work creating the wetlands necessary to sustain healthy duck populations.

The field of waterfowl science came into existence at about the same time. One of the earliest researchers was Hans Albert Hochbaum, a colleague of Aldo Leopold who became Delta Waterfowl’s first scientific director in 1938.

The roles of science and conservation organizations were clearly defined: Scientists would study ducks and pass along their findings to waterfowl managers for implementation.

But conservationists were so focused on wetland restoration—which usually meant putting permanent water on the landscape—they didn’t seem to hear the scientists telling them water was just one component of the total ecosystem ducks required to be productive. To those in the conservation movement, every acre of water protected, created or restored was a milestone that put us closer to the goal of filling the fall sky with ducks.

Wetland acres—not ducks—became the yardstick by which success was measured.

Before he died in 1948, Leopold expressed his concern about the course wildlife management was charting when he wrote, “American conservation is, I fear, still concerned for the most part with show pieces. We have not yet learned to think in terms of small cogs and wheels.”

No thoughtful sportsman would question the value of wetland habitat. Wetlands are one of the cogs mentioned by Leopold, and they perform a myriad of beneficial functions for ducks and for the environment. But if the issue on the table is duck production, the question hunters must ask is, “How effective have our wetland-restoration dollars been at putting more ducks in the sky?”

And that’s where the picture goes out of focus.

Paper Ducks?

The proof, they say, is in the pudding, and what more compelling evidence that wetland restoration produces healthy duck populations than the “all-time record fall flight of 1999”?

The logical projection of those claims was that efforts to protect wetlands were responsible for the 1990’s jump in duck numbers. Like Johnny Carson used to say, “If you buy the premise, you’ll buy the story.”

With that in mind, let’s examine the premise.

The fall flight index (FFI) dates back only to 1970, so when someone calls the fall flight of 1999 “an all-time record”, what they actually mean is it was the “highest index since 1970”.

The operative word here is “index”. Scientists tell us the FFI was never intended to be an exact population figure, only an indicator of year-to-year population trends.

Few would argue that the latter years of the ‘90s produced some excellent fall flights. The 1997, ’98 and ’99 seasons may well have been as good as anything we saw in the 1970s.

But those who experienced duck hunting in the ‘50s aren’t buying the notion

of record flights in the ‘90s. Says Harold Duebbert, a retired US Fish and Wildlife biologist who has been hunting the same area of North Dakota since the late 1950s, “I remember the freeze-up flight of ’58. For three days and nights, flocks of ducks filled the sky, far as a man could see. We’ve had some big flights since 1993, but nothing like that.”

Dean remembers that year, too. “In 1958 my dad and I were hunting a wetland north of Wing (ND). At about 3 in the afternoon the sky turned black with ducks—mallards and pintails mostly. My dad told me to unload my gun. When I asked why, he said, ‘Because you’re never going to see anything like this again in your lifetime.’”

Were the incredible scenes they witnessed in the ‘50s replicated in the 1990s?

Were the fall flights of the ‘90s greater than those of a century earlier?

Only on paper.

What Does the Science Say?

The above comments are strictly anecdotal, of course, but they came from experienced waterfowl observers who hunted through the three most recent duck booms. They’ve been watching the same skies across the same duck-producing states for more than half a century, which for this layman gives them more credibility as those using circumstantial evidence to certify a record flight.

Anecdotal evidence is better than no evidence at all.

But in an effort to keep this discussion academically correct, the jury will disregard the anecdotal testimony and focus on the science. What did the experts say about the fall flights of the ‘90s?

The US Fish and Wildlife Service didn’t have much faith in the fall flight index, and recognized that the FFI was producing unrealistic expectations—and in many cases disappointment—among hunters.

Says Jerry Serie of the Office of Migratory Bird Management in Laurel, MD,

“The FFI wasn’t a very reliable index, and we didn’t have a lot of confidence in it. It was a bit of a stretch, and that’s why we stopped using it after 1999.”

But if the FFI was discontinued after ’99, the claims of a record flight persist even today. We recently read an article—written by a waterfowl scientist—claiming the harvests of the late 1990s were comparable to the harvests of the 1970s, but because there were only half as many hunters in the ‘90s, the hunting seasons were “twice as good as those of a generation ago.”

Statistics don’t lie, but they certainly can be used to mislead. The author didn’t bother to mention that the number days hunters spent in the field in the late ‘90s was comparable to the number of hunter-days in the ‘70s. He also failed to mention that the number of hunter-days in the Mississippi Flyway—where a high percentage of the continent’s birds are harvested—was actually higher during the ‘90s duck boom than during the ‘70s.

The same article claimed that duck populations in the 1990s were “comparable to those of the 1950s”. That statement—a candidate for the Anecdotal Evidence Hall of Fame—is likely based on the spring breeding population of ducks, which in the waning years of the ‘90s was comparable to the record B-pops of 1958.

You don’t need a PhD to wonder how 40 million breeding ducks in the ‘90s produced the same fall flight as 40 million breeding birds in 1958.

Science tells us nest success across the prairie pothole region (PPR) dropped from 21 percent in 1955 to 15 percent in 1972 and 10 percent by 1992. Is it reasonable to expect that 40 million breeding ducks experiencing 10 percent nest success in the ‘90s could produce a larger fall flight than the same number of breeding ducks in the 1950s, a time when nest success was more than double?

One could argue that when seasonal wetlands are abundant, ducks can overwhelm poor nest success with repeated nest initiations. Ducks just keep trying until they’re successful or run out of time.

But didn’t that same thing happen in the 1950s?

What do the age ratios—another scientific measure of production—tell us? Age ratios confirm that production has been steadily falling since the 1960s.

Our best science has told us nesting puddle ducks need large blocks of grass cover to be successful. In Saskatchewan alone, 10 million acres of native prairie have been put into crop production since the 1950s, and grassland and wetland losses across the rest of prairie Canada and the US portion of the pothole region have been dramatic since the ‘50s.

In the face of such staggering habitat losses, is it logical that recruitment in the ‘90s was better than it was in the ‘50s? Is it possible the ‘90s produced more ducks than the 19th century, when the breeding grounds were a vast sea of grass punctuated by millions of wetlands and occupied by predators that rarely messed with ducks and duck eggs?

More to the point: Where’s the proof?

If It Ain’t Broke, Don’t Fix It

The real issue isn’t whether or not 1999 actually produced a record fall flight of ducks. The danger is that if we believe the ‘90s produced more ducks than any other era in history, it follows that our efforts to restore habitat have been so successful that we can ignore decades of science suggesting the need for other management tools.

If waterfowl management believes everything it needs to know about duck production exists in the habitat box, will it stop looking outside the box for answers?

Our best scientific minds haven’t been afraid to look outside the box. Thanks to their efforts, our understanding of ducks mushroomed during the ‘90s, and much of what we learned suggests that the prairie ecosystem has evolved faster than the conservation movement’s ability to keep pace.

Study after study has pointed up a need for the application of management tools that supplement our dwindling habitat base. Study after study has shown that habitat projects scattered across an otherwise fragmented landscape do not produce the nest success necessary for the population to expand.

That doesn’t mean we should stop preserving habitat. Habitat is the first and foremost ingredient in the recipe for making ducks, and if anything we need to step up our efforts to preserve every square inch, especially in the prairie pothole region.

Likewise, we can no longer ignore the science pointing up the need for additional management tools.

The irony is that the conservation movement’s justification for ignoring the findings of our finest scientific minds is the claim of a record fall flight, a claim supported only by a few threads of same anecdotal evidence scientists abhor.