July 29, 2005
Migrating ducks returning to important nesting areas in the north-central
United States and southern Canadian prairies early this spring were greeted
by dry conditions, according to the U.S. Fish and Wildlife Service's annual
However, the U.S. and Canadian prairies received substantial rain in late
May and during the entire month of June that recharged wetlands and
encouraged growth of vegetation. While this improved habitat quality on the
prairies, it probably came too late to benefit early-nesting species or
waterfowl from breeding farther north.
"We are certainly excited about the amount of rain that fell on the
prairies and parklands since late May," said Acting Service Director Matt
Hogan. "We don't know what impact it will have on production but likely the
rains benefited late nesting and re-nesting efforts. It does bode well for
maintaining nesting water this year and perhaps better habitat conditions
The Waterfowl Breeding Population and Habitat Survey, which is 50 years old
this year, is the largest and most comprehensive survey of its kind in the
world. The survey samples 2.2 million square miles across the northcentral
and northeastern United States, Canada and Alaska. Pilot-biologists who fly
the survey estimate the number of ducks in the continent's most important
nesting grounds, commonly referred to as the traditional survey area. Many
State and Canadian partners help collect the data.
In the traditional survey area of western Canada, Alaska and the
northcentral United States, the total duck population estimate (excluding
scoters, eiders, long-tailed ducks, mergansers and wood ducks) is 31.7
million birds. This estimate is not statistically different from last
year's estimate of nearly 32.2 million birds. It is 5 percent below the
- Mallard abundance was 6.8 million birds, which is 9 percent below last
year's estimate of 7.4 million birds and 10 percent below the long-term
- Blue-winged teal were estimated at 4.6 million birds. This value was
similar to last year's estimate of 4.1 million birds and the long-term
- Among other duck species, northern pintail, at 2.6 million, and northern
shovelers, at 3.6 million, were significantly above 2004 estimates, while
the estimate for the gadwall, 2.2 million, was below the 2004 survey
results. Scaup abundance, at 3.4 million, was the lowest ever recorded on
the survey. Biologists are studying the reasons for the decline.
- In comparison with long-term averages, the 2005 estimates were higher for
gadwall -- up 30 percent, northern shoveler -- up 67 percent, and
green-winged teal at 2.2 million -- up 16 percent. The 2005 estimates as
compared to the long-term average were lower for northern pintail -- down
38 percent, American wigeon at 2.2 million -- down 15 percent, and scaup
down 35 percent. Estimates for the redhead, at 592,000, and canvasback, at
521,000, were similar to their long-term averages.
Across traditional duck nesting areas of western Canada and the
north-central United States, total pond numbers were 37 percent higher than
last year. This increase is primarily the result of changes in Canada,
where pond numbers increased 56 percent to 3.9 million ponds. In the
northcentral United States, nearly 1.5 million ponds were observed, similar
to last year's estimate.
Nesting habitat was particularly poor in South Dakota because below average
precipitation allowed tilling and grazing of wetland margins. Birds may
have flown over the State for wetter conditions to the north.
Water levels and upland nesting cover were better in North Dakota and
eastern Montana, and wetland conditions in these regions improved markedly
during June with the onset of well-above average precipitation. The
prairies of southern Alberta and southwestern Saskatchewan were quite dry
in early May.
The Canadian Parklands fared much better this year, due to a combination of
several years of improving nesting cover and above-normal precipitation
last fall and winter. These areas were in good-to-excellent condition at
the time of the survey. and conditions have remained good through early
summer. Record high levels of rain flooded portions of lower elevation
prairie areas of central Manitoba during April, producing fair or poor
nesting conditions for breeding waterfowl in some areas. Portions of
northern Manitoba and northern Saskatchewan also experienced flooding,
resulting in only fair conditions for breeding waterfowl.
Most of the Northwest Territories were in good condition due to adequate
water and a timely spring thaw that made habitat available to early-nesting
species. However, dry conditions in eastern parts of the Northwest
Territories and northeastern Alberta resulted in low water levels in lakes
and ponds and the complete drying of some wetlands. Habitat was classified
as fair in these areas.
Annual survey results help guide the Service in managing its waterfowl
conservation programs under the 1918 Migratory Bird Treaty Act. The Service
works in partnership with State representatives from the four flyways - the
Atlantic, Mississippi, Central and Pacific - to establish regulatory
frameworks for waterfowl hunting season lengths, dates and bag limits.
Alaska was in mostly excellent condition, with an early spring and good
water, except for a few flooded river areas and the North Slope, where
spring was late.
In the eastern United States and Canada, habitat conditions were good due
to adequate water and relatively mild spring temperatures. The exceptions
were the coast of Maine and the Maritimes, where May temperatures were cool
and some flooding occurred along the coast and major rivers. Also,
below-normal precipitation left some habitats in fair to poor condition in
southern Ontario at the time of the survey. However, precipitation in this
region following survey completion improved habitat conditions.
In eastern North America, the Service and Canadian Wildlife Service are
developing new methods of integrating data from multiple surveys. As a
result, estimates for the eastern survey area are not directly comparable
to those reported in previous years. In the eastern survey area, the
American black duck population estimate was 827 thousand birds, a decrease
of 24 percent from last year's estimate of 1.1 million but similar to the
1999-2004 average. The estimate for the mallard, at 412 thousand birds,
declined 36 percent from 2004, but was similar to the 1999-2004 average.
To see the full results of the survey, which includes graphs and maps,
http://migratorybirds.fws.gov/reports/reports.html. To see how the
survey is conducted and learn about the Survey's 50th anniversary, please