Duck hunters have to be a little like the guy who won't buy green bananas. Like the uncertain shopper who doesn't count on being around when the fruit ripens, waterfowlers never know for sure when their seasons will open and close until a few weeks before it's time to don camo and settle into the blind.

That's because ducks and geese live very different lives than turkeys and deer. With some exceptions, waterfowl doesn't stay put. Because flocks that hunters try to lure into range may have hatched half a continent away, biologists from the states, Canadian provinces, U.S. Fish and Wildlife Service (USFWS), Canadian Wildlife Service, Mexican Ministry of the Environment and Natural Resources and private organizations such as Ducks Unlimited cooperate every spring and summer to survey waterfowl populations across North America.

As part of the North American Waterfowl Management Plan launched in 1989, biologists fly, float and slog the continent's wetlands counting birds. After the data is analyzed, each state and province sets its waterfowl seasons within a framework offered by the respective federal wildlife agencies. While Pennsylvania deer hunters know their season schedule each April, waterfowlers generally learn the exact season dates for ducks and geese in mid-August.

"A big part of why the seasons are announced so late is because the recommendations are based on survey data on the nesting grounds, and some of that information cannot be accumulated until as late as late July," Game Commission biologist John Dunn said.

Early seasons are expected to be announced this week on the Game Commission's website (www.pgc.state.pa.us). Complete waterfowl seasons and bag limits will be published later this month.

At a public session held near Harrisburg August 6, the Game Commission briefed hunters on survey results and the status of waterfowl populations on the Atlantic Flyway, which includes much of Pennsylvania, stretching from northeastern Canada, south along the coast to the southern Gulf of Mexico.

According to the 2010 Atlantic Flyway Breeding Waterfowl Plot Survey report written by the Fish and Wildlife Service's John D. Klimstra, favorable habitat conditions existed across much of the flyway in early spring. Within Pennsylvania and the surrounding region, melt water from heavy snow and abundant rainfall recharged wetlands and streams and favored nesting. But much of the flyway experienced hot dry weather soon after, and the ultimate success of nesting and brooding appears mixed.

Among the duck species most sought by Pennsylvania hunters, the mallard duck population is estimated to have declined by 2 percent in the Atlantic Flyway from 2009. More significantly, biologists say, the 2010 estimate is 15 percent below the long-term average, deemed a more reliable benchmark.

In contrast, 2010 flyway wood duck estimates are 11 percent higher than 2009 and 9 percent above the long-term average.

Survey results from within Pennsylvania for these species in 2010 were similar. Estimates of Pennsylvania-hatched wood ducks are 10 percent above the long-term average, but mallard estimates are below that gauge by 18 percent.

Biologists note the apparent decline in both Atlantic Flyway and Pennsylvania mallard estimates, but say they think the dip can be accounted for and are not alarmed.

"A decline in mallard abundance was expected following liberalized hunting frameworks adopted in 1996 through Adaptive Harvest Management. Managers expect this trend to stabilize," said Game Commission biologist Kevin Jacobs, who supervised the annual survey within Pennsylvania.

But even the hard-won survey data can't reliably predict the number of birds that will actually be available to Pennsylvania gunners once the seasons do open.

"Timing of hunts in relation to weather patterns and in optimal habitats that hold birds always greatly affects the numbers of birds [that] hunters observe," Jacobs said. "For our most important species -- mallard, wood duck and resident Canada goose -- I expect bird numbers to be near average this fall."

The trend in wood duck numbers should especially please Western Pennsylvania waterfowlers.

"Trends in wood duck abundance have indicated stable to slightly increasing populations across all years of the survey. Wood duck densities were highest in Northwestern and Southwestern Pennsylvania," Jacobs said.

Hunter reports of wood duck leg bands show that 83 percent of wood ducks taken by Pennsylvania hunters were hatched in the state. Meandering streams within woodlands, common across Western Pennsylvania, are ideal habitat for the species.

Jacobs predicts good hunting for resident Canada geese this fall, but says hunters will pursue a population that is no longer growing at the explosive rate it once was. Resident geese often cause problems for farmers, municipal governments and golf course managers.

"The Pennsylvania Canada goose spring breeding population appears to have stabilized near 250,000 birds following the rapid growth observed during the 1990s," Jacobs said. "This is a result of significant expansion of hunting seasons and other lethal and non-lethal programs implemented to control Canada goose numbers."

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