By most measures, recent years have been good for ducks and duck hunters. With good average moisture for the past two decades, populations have seemingly flourished.

“Overall, populations have been favorable,” says Dale Humburg, chief biologist for Ducks Unlimited.

While that generalization is certainly good news, the more specific reality of the situation tends to follow the tired, old cliché that the devil is in the details. Or so the saying goes.

The truth is, not all species are thriving.

“There are ducks that are winning and ducks that are losing,” says John Devney, senior vice president of Delta Waterfowl. “The makeup of the breeding population is far different today than it used to be.”

Populations of mallards, gadwalls, northern shovelers, redheads, blue-winged teal and green-winged teal are all increasing. On the other hand, species like American wigeon, northern pintail, canvasback and scaup are decreasing.

The reasons for those increases and declines are specific to the biology of the species and their needs during an average season, which given the nature of waterfowl, can be quite a complex riddle to tease out sometimes. But like most wildlife, the problem’s overarching theme is the decline of quality habitat.

To understand that link, we first have to back up a little bit. Waterfowl populations are highly dependent on conditions and availability of good habitat. If you have poor conditions and shrinking availability during nesting season, it stands to reason you’re going to see that impact almost immediately. Unlike other species, which will show gradual cycles of increase and decline based on conditions, waterfowl are more closely linked to those changes, mirroring those trends much more intimately.

It also stands to reason that waterfowl are dependent on the quantity of habitat and are also immensely dependent on the quality of habitat. Good habitat equals stronger populations and thus happy hunters.

For some species, a decline in quality habitat can be quite a significant hit. For others, it’s more easily absorbed.

For instance, Humburg says, mallards are quite resilient. With an average nest size of 10 eggs or more, they can produce large numbers of birds any year and tend to be more adaptable than other species with restrictive habitat needs.

On the other hand, species such as scaup don’t paint quite as clear a picture. Scientists are still looking for a definitive reason to explain their decline, but suspect things such as deteriorating winter habitat and possibly the role contaminants may play during breeding season.

“There are a number of things going on there,” Humburg says. “But the jury is still out.”

And while individual populations have their own complexities, even the story behind the general population picture has some shades of gray. In fact, while the overall trend looks quite rosy, the ability for that population to maintain those numbers is precarious at best when one considers where most ducks are being produced.

Most species utilize the Dakotas and prairie Canada as breeding grounds. On one side of the border (the Dakotas), that process seems to be going quite well. But on the other side of the border, it’s another story.

According to data from U.S. Fish and Wildlife Service’s annual report on population trends issued July 2011, breeding population estimates are starkly different in Canada when compared to the United States. For 2010, numbers were up 172 percent in the eastern Dakotas and 92 percent in Montana and the western Dakotas when compared to the long-term average. However, those numbers were in the single digits everywhere in Canada except southern Saskatchewan, which saw a 43-percent increase in 2010. In northern Saskatchewan, northern Manitoba and western Ontario, there was even a 30-percent decrease in the breeding population estimates when compared to the long-term average.

Much has been said and written on the problems prairie Canada faces, but to sum it up, the issue here, not surprisingly, is habitat and policies regarding habitat. According to Devney, the rate of wetlands loss in prairie Canada is the same today as it was back in the 1970s. That is to say, not good. And incentives to slow down that loss are few.

What that all means is, in recent years, the U.S. has been overcompensating, churning out ducks as if it were going out of style. And for the most part that has worked; when one side of the border wasn’t doing so well, inevitably the other side compensated.

“So far (poor habitat conditions) haven’t really occurred at the same time,” Humburg says. “We’ve ended up with the U.S. compensating with changes in Canada and Canadian conditions compensating in some years and vice versa.”

But when one area is carrying the brunt of the burden, any problems that area has can become even more, well, problematic. The stakes suddenly become higher. Case in point: the loss of native grasslands and wetlands.

The loss of native grasslands and wetlands has been a problem for decades. And while it might not feel immediately pressing, it’s like a steadily dripping faucet; one drip doesn’t seem like much until you’re suddenly hauling around a five-gallon bucket.

“The U.S. has shouldered the load,” Devney says. “As we lose CRP, native grasslands and wetlands, and as resources get put under risk, we start to fly without a net. I wouldn’t presuppose the next 20 years will be like the last 20 … We’ve enjoyed a period of remarkable abundance. We have a generation of duck hunters who don’t know anything but liberal seasons and bag limits, and that’s been great. But there are definitely some things we need to keep our eyes on.”

That bucket is quickly filling for habitat on both sides of the border. And when it’s gone, it’s gone. There’s no easy fix. The problem is, fixing Canada isn’t going to happen overnight. And the way things have been going, if the Dakotas go down, it won’t just be a slight blip on the population radar. It stands to be a plummeting drop.

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