In normal times, an abundance of springtime potholes on the northern prairies and an increase in numbers of breeding ducks would be cause for jubilation. The combination would produce a bountiful hatch of young, resulting in impressive numbers of ducks winging southward.

This year’s survey of the North American breeding grounds appeared to reflect these conditions. Biologists flying the aerial transects estimated the number of potholes this May totaled 6.1 million, an increase of 13 percent over 2005. This total reflects excellent water conditions.¹ Numbers of potholes for the years 1999-2006 can be seen in the following chart.

North American Potholes

1999 2000 2001 2002 2003 2004 2005 2006

Year

In addition, the number of ducks counted on the breeding grounds jumped from 31.7 million last year to 36.2 million this spring, an increase of 14 percent. The all-important mallard breeding population totaled 7.3 million, an increase of 8 percent.

This year’s breeding population estimates for 10 species of ducks from the traditional North American survey area, with percentage changes from last year, are as follows:

The breeding population increases in eight of 10 species prompted some authorities in early summer to sing hosannas, as if hunters could expect a bountiful fall flight. “We’re quite pleased,” enthused Don Young, executive vice president of Ducks Unlimited. Rob Olson, president of Delta Waterfowl, declared, “Mother Nature has set the table for ducks.”

Yet, as all of us know, these are not normal times – for ducks or anything else. Madduck’s analysis of the data suggests most hunters this autumn will witness a fair-tomiddlin’ migration, especially for mallards, with the shooting quality dependent on weather and the exodus from the breeding grounds.

The reason for our contrarian forecast involves both water and breeding populations.

Despite the high pothole count marking the third consecutive year of increasing water, the U.S. Fish and Wildlife Service reported that “spring precipitation in the grasslands of southern Saskatchewan and extreme southwestern Manitoba was insufficient to fill seasonal and semi-permanent wetlands or create temporary wetlands for waterfowl, leaving these regions in fair or poor condition.” Conditions improved in southern Alberta, an important pintail nesting region, but “central Alberta remained dry.”

On the American prairies, nesting habitat was only “minimally” improved this spring along parts of the easternmost regions of the Dakotas. “The Drift Prairie, the Missouri Coteau and the Coteau Slope remained in fair to poor condition due to lack of temporary and seasonal water,” the service said. It added that by May “permanent wetlands were typically in various stages of recession.”

All of this was exacerbated by a severe summer drought in portions of the Great Plains.

None of this suggests wetland conditions the northern prairies this spring and summer encouraged a bountiful hatch of young, as might be indicated by a high pothole count.

A second factor involves numbers of breeding ducks, which were far below the number that might be expected after three consecutive years of improving water conditions. In 1999, the last year of “high” water (more than six million potholes),

The breeding populations for eight other species – gadwall, widgeon, green-winged teal, blue-winged teal, shovelers, canvasback, redhead and scaup – also were much higher in 1999 than this spring.

Thus, we not only have too few breeders to occupy the available habitat, but this spring’s comparatively fewer breeders faced diminishing nest and fledging success due to progressively deteriorating wetland conditions. This tells us the fall flight probably will be somewhat smaller than last year, certainly no greater, especially for mid-continent mallards. The overall fall-flight will be fair-to-middlin’. The flight will be significantly smaller than that of 1999, the last year of similar high water conditions. The U.S. Fish and Wildlife Service predicts a mallard fall flight equal to last year.

The lone exception to this general rule is California. Its local nesting mallard population produced a bumper crop of young this spring.

There is, however, one development that could affect the fortunes of some waterfowl hunters. The intense summer drought that has struck the mid and lower Great Plains may cause significant numbers of southbound ducks to shift flight patterns, boosting populations in nontraditional areas with water.

¹ The number of North American potholes has ranged from a low of 2.1 million to a high of 8.2 million. As a rule of thumb, northern prairie water conditions can be classified as low when the number of potholes ranges from 2.0 million to 3.9 million, average when the number ranges from 4.0 million to 5.9 million, and high when the number exceeds 6.0 million. The long-term average is slightly more than 5 million.

2 biologists counted a total of 10.8 million mallards, compared to only 7.3 million this year. The waterfowl management mallard population goal is 8.2 million mallards under “average” wetland conditions.