The results of the U.S. Fish & Wildlife Service's 2012 Waterfowl Breeding Population and Habitat Survey are in, and the news should please duck hunters. Based on aerial surveys over more than 2 million square miles, the estimate of total ducks in North America was 48.6 million, up from last year's of 45.6 million and 43 percent greater than the 1955-2008 long-term average.
The key to waterfowl populations is habitat, measured as the number of ponds, the result of the past year's snow melt and rainfall. The total pond estimate for the continent's "duck factory," the prairie provinces of Canada and northern prairie states of the U.S., was 5.5 million, about 9 percent above the long term average of 5.1 million ponds.
Ducks require the nesting habitat surrounding ponds and the water itself to provide food and refuge. Simply stated, wet years produce more ducks; drought years cause duck numbers to plummet.
The vast majority of North America's ducks nest around the potholes that dot the Dakotas, Minnesota, eastern Montana and Canada's prairie provinces. And many of these birds migrate east and south to east coast wintering grounds.
During drought years, potholes dry up and farmers cultivate these depressions in the landscape. This forces ducks to nest in increasingly fewer wetlands and that makes nests easier for predators to find. Drought imposes a double whammy on duck populations -- less habitat and higher predation rates.
That's why the annual Waterfowl Surveys are so important. Only by knowing where populations stand compared to past surveys can biologists manage duck populations by adjusting duck hunter seasons, dates and bag limits.
Mallards are widespread and abundant across the continent so it's instructive to focus on them. As mallards go, so go other duck species.
This year the estimated mallard population was 10.6 million birds, 15 percent higher than last year and 39 percent more than the long term average. But these numbers mean little without knowledge of historic extremes.
The best mallard years came in 1956 (10.4 million mallards), 1958 (11.2 million), and 1999 (10.8 million). The worst mallard years were, 1965 (5.1 million), 1984 (5.4 million), and 1985 (5.0 million). So while this year's count is nearly double the worst years' numbers, it is still below the highest counts.