by Matt Young
Habitat drives duck populations, and in 2010 breeding waterfowl returned to generally good wetland conditions across much of the prairie Duck Factory. The U.S. Fish and Wildlife Service (USFWS) reports that this year's estimate of 6.7 million May ponds—the unit of measure for wetland abundance on the prairies—was 34 percent above the long-term average. The total breeding duck estimate in the traditional survey area was almost 41 million birds—equivalent to the 2009 estimate and the seventh-largest since surveys began in 1955.
Populations of all major duck species were statistically similar to those of last year except for blue-winged teal, which posted a 14 percent decline from the previous year but remained well above the long-term average. Taking a closer look at the numbers, this year's mallard population of 8.4 million birds was almost unchanged from 2009 and near a 10-year high. Pintails had a population of 3.5 million birds—the largest estimate for this species since 1997 and near a 30-year high. In more good news for waterfowlers, record numbers of green-winged teal and redheads were surveyed this spring on major waterfowl breeding areas. Gadwalls and shovelers also remained at high population levels, and canvasbacks and American wigeon held near their long-term averages. Lastly, this year's scaup population of 4.2 million birds was also unchanged from 2009 levels but significantly higher than their all-time low of 3.2 million birds in 2006.
"This year's survey numbers were certainly encouraging, as most waterfowl species were at or above their long-term averages," says DU Chief Biologist Dale Humburg. "Moreover, wetland conditions held up or improved in many regions after the surveys were completed, which likely encouraged renesting and provided favorable habitat for hens and broods. While I'm optimistic about the 2010 fall flight, we should keep in mind that weather and habitat strongly influence the timing and distribution of migrating waterfowl, as well as how many birds we see from our blinds."
May pond counts and waterfowl breeding population estimates are compiled during extensive air and ground surveys conducted by the USFWS, Canadian Wildlife Service, state and provincial wildlife agencies, and other partners. These surveys are essential to managing waterfowl populations and setting annual hunting regulations. The following report provides an overview of the status of habitat conditions and waterfowl populations across key breeding areas in the United States and Canada.
Fig. 1. 2010 Estimates of May Ponds and Breeding ducks – click image to enlarge
||On the prairies, frequent spring and summer rains created excellent wetland habitat for breeding waterfowl.
Jason Riopel, DU
The Pacific Flyway receives most of its waterfowl from the western United States and Canada, with the majority of the flyway's ducks and geese coming from Alberta, Alaska, British Columbia, the Yukon, the Northwest Territories, and other western states. In 2010, an estimated 2.6 million breeding ducks were surveyed across the grasslands and parklands of Alberta—a 20 percent decline from the 2009 estimate and significantly below the long-term average. On the upside, pintail numbers increased 41 percent in the region compared to the previous year. Shortly after waterfowl surveys began in May, frequent precipitation dramatically improved wetland conditions across southern Alberta.
"The prairie was wetter this summer than anyone has seen in years," says DU Canada biologist Ian MacFarlane. "Wetlands that have not held significant water for at least 25 years are now flooded and providing excellent waterfowl habitat. Abundant precipitation also created good wetland conditions in the southern parklands but arrived too late for many spring migrants. More precipitation was needed to recharge wetland basins in the northern parklands. Overall, waterfowl production was expected to be above average on the prairies and below average in the parklands."