Waterfowl population status, 2005

              Waterfowl
Population Status, 2005
U.S. Fish and Wildlife Service
WATERFOWL POPULATION STATUS, 2005
July 25, 2005
In North America the process of establishing hunting regulations for waterfowl is conducted annually. In the
United States the process involves a number of scheduled meetings in which information regarding the status of
waterfowl is presented to individuals within the agencies responsible for setting hunting regulations. In addition
the proposed regulations are published in the Federal Register to allow public comment. This report includes
the most current breeding population and production information available for waterfowl in North America and is
a result of cooperative efforts by the U.S. Fish and Wildlife Service (FWS), the Canadian Wildlife Service
(CWS), various state and provincial conservation agencies, and private conservation organizations. This report
is intended to aid the development of waterfowl harvest regulations in the United States for the 2005-2006
hunting season.
________________________________________________________________________________________
Cover art: Hooded mergansers. Mark Anderson winner of the 2005-2006 Federal Duck Stamp design competition.
ACKNOWLEDGMENTS
Waterfowl Population and Habitat Information: The information contained in this report is the result of the efforts
of numerous individuals and organizations. Principal contributors include the Canadian Wildlife Service, U.S.
Fish and Wildlife Service, state wildlife conservation agencies, provincial conservation agencies from Canada,
and Direccion General de Conservacion Ecologica de los Recursos Naturales, Mexico. In addition, several
conservation organizations, other state and federal agencies, universities, and private individuals provided
information or cooperated in survey activities. Some habitat and weather information was taken from the
NOAA/USDA Joint Agriculture Weather Facility (http://www.usda.gov/oce/waob/jawf/), Environment Canada
(http://www1.tor.ec.gc.ca/ccrm/bulletin/), and Waterfowl Population Surveys reports
(http://migratorybirds.fws.gov/reports/reports.html). Appendix A provides a list of individuals responsible for the
collection and compilation of data for the Ducks section of this report. Appendix B provides a list of individuals
who were primary contacts for information included in the Geese and Swans section. We apologize for any
omission of individuals from these lists, and thank all participants for their contributions. Without this combined
effort, a comprehensive assessment of waterfowl populations and habitat would not be possible.
Authors: This report was prepared by the U.S. Fish and Wildlife Service, Division of Migratory Bird
Management, Branch of Surveys and Assessment. The principal authors are Pamela R. Garrettson, Timothy J.
Moser, and Khristi Wilkins. The authors compiled information from the numerous sources to provide an
assessment of the status of waterfowl populations.
Report Preparation: The preparation of this report involved substantial efforts on the part of many individuals.
Support for the processing of data and publication was provided by Mark C. Otto, John Sauer and Judith P.
Bladen. Ray Bentley, John Bidwell, Karen Bollinger, Elizabeth Huggins, Bruce Conant, Carl Ferguson, Rod
King, Mark Koneff, Fred Roetker, John Solberg, Phil Thorpe, Dan Nieman, Dale Caswell, James Kelley, James
Dubovsky, Robert Blohm, and James Wortham provided habitat narratives, reviewed portions of the report that
addressed major breeding areas, and provided helpful comments.
This report should be cited as: U.S. Fish and Wildlife Service. 2005. Waterfowl population status, 2005. U.S.
Department of the Interior, Washington, D.C. U.S.A.
All Division of Migratory Bird Management reports are available at our home page
(http://migratorybirds.fws.gov).
This year is the 50th anniversary of the May Waterfowl Breeding Population and Habitat Survey.
Table of Contents
ACKNOWLEDGMENTS.................................................................................................................... 2
Status of Ducks
METHODS ........................................................................................................................................ 5
RESULTS AND DISCUSSION........................................................................................................... 7
REFERENCES.................................................................................................................................. 29
Status of Geese and Swans
METHODS ........................................................................................................................................ 30
RESULTS AND DISCUSSION........................................................................................................... 32
Appendices
Appendix A. Individuals that supplied information on the status of ducks ........................................ 46
Appendix B. Individuals that supplied information on the status of geese and swans ..................... 48
Appendix C. Transects and strata for areas of the May Waterfowl Breeding Population and Habitat
Survey .................................................................................................................................. 50
Appendix D. Estimated number of May ponds and standard errors in portions of Prairie and
Parkland Canada and the northcentral U.S. ......................................................................... 51
Appendix E. Breeding population estimates for total ducks and mallards for states, provinces,
or regions that conduct spring surveys ................................................................................. 52
Appendix F. Breeding population estimates and standard errors for 10 species of ducks
from the traditional survey area ............................................................................................ 54
Appendix G. Total duck breeding estimates for the traditional survey area, in
thousands............................................................................................................................. 56
Appendix H. Breeding population estimates (median, in thousands) and 95% credibility intervals
(CI) for 6 species of ducks in the eastern survey area, 1999-2005…………………………...57
Appendix I. Population indices for North American Canada goose populations, 1969-2005 ........... 58
Appendix J. Population indices for light goose, greater white-fronted goose, brant, emperor
goose, and tundra swan populations during 1969-2005....................................................... 59
3
List of Duck Tables
Table 1. Estimated number of May ponds in portions of Prairie and Parkland Canada and the
northcentral U.S. .................................................................................................................. 9
Table 2. Total duck breeding population estimates .......................................................................... 11
Table 3. Mallard breeding population estimates ............................................................................... 12
Table 4. Gadwall breeding population estimates.............................................................................. 17
Table 5. American wigeon breeding population estimates ............................................................... 17
Table 6. Green-winged teal breeding population estimates ............................................................. 18
Table 7. Blue-winged teal breeding population estimates ................................................................ 18
Table 8. Northern shoveler breeding population estimates .............................................................. 19
Table 9. Northern pintail breeding population estimates .................................................................. 19
Table 10. Redhead breeding population estimates .......................................................................... 20
Table 11. Canvasback breeding population estimates ..................................................................... 20
Table 12. Scaup (greater and lesser combined) breeding population estimates ............................. 21
Table 13. Duck breeding population estimates (median, in thousands) for 6 species in the
Eastern Survey area ............................................................................................................. 21
List of Duck Figures
Figure 1. Number of ponds in May and 95% confidence intervals for Prairie and Parkland
Canada and the northcentral U.S. ....................................................................................... 9
Figure 2. Breeding population estimates, 95% confidence intervals, and North American
Waterfowl Management Plan population goal for selected species for the traditional
survey area .......................................................................................................................... 13
Figure 3. Median population size and credibility intervals for 6 species in the Eastern Survey Area
(strata 51-72)......................................................................................................................... 26
Figure 4. Estimates and 95% confidence intervals for the size of the mallard population in the
fall......................................................................................................................................... 28
List of Goose and Swan Figures
Figure 1. Important goose nesting areas in arctic and subarctic North America ............................. 31
Figure 2. Snow and ice cover in North America for spring ............................................................... 32
Figure 3. Approximate ranges of Canada goose populations in North America............................... 33
Figures 4-18. Indices to Canada goose populations’ status ............................................................ 32-39
Figure 19. Approximate ranges of selected goose populations in North America............................ 40
Figures 20-26, 28. Indices to selected goose populations’ status ................................................... 41-45
Figure 27. Approximate range of Emperor goose, and tundra swan populations in
North America ....................................................................................................................... 45
Figure 29. Indices to tundra swan populations’ status...................................................................... 45
4
STATUS OF DUCKS
Abstract: In the Waterfowl Breeding Population and Habitat Survey traditional survey area (strata 1-18, 20-50,
and 75-77), the total duck population estimate was 31.7 ± 0.6 [SE] million birds, similar to last year’s
estimate of 32.2 ± 0.6 million birds but 5% below the 1955-2004 long-term average. Mallard (Anas
platyrhynchos) abundance was 6.8 ± 0.3 million birds, which was 9% below last year’s estimate of 7.4 ±
0.3 million birds and 10% below the long-term average. Blue-winged teal (A. discors) abundance was 4.6
± 0.2 million birds, similar to last year’s estimate of 4.1 ± 0.2 million birds, and the long-term average. Of
the other duck species, the gadwall estimate (A. strepera; 2.2 ± 0.1 million) was 16% below that of 2004,
while estimates of northern pintails (A. acuta; 2.6 ± 0.1 million; +17%) and northern shovelers (A.
clypeata; 3.6 ± 0.2 million; +28%) were significantly above 2004 estimates. The estimate for northern
shovelers was 67% above the long-term average for this species, as were estimates of gadwall (+30%)
and green-winged teal (A. crecca; 2.2 ± 0.1 million; +16%). Northern pintails remained 38% below their
long-term average despite this year’s increase in abundance. Estimates of American wigeon (A.
americana; 2.2 ± 0.1 million; -15%) and scaup (Aythya affinis and A. marila combined; 3.4 ± 0.2; -35%)
also were below their respective long-term averages; the estimate for scaup was a record low.
Abundances of redheads (A. americana) and canvasbacks (A. valisineria) were similar to last year’s
counts and long-term averages. The total May pond estimate (Prairie and Parkland Canada and the
northcentral U.S. combined) was 5.4 ± 0.2 million ponds, which is 37% greater than last year’s estimate of
3.9 ± 0.2 million ponds and 12% higher than the long-term average of 4.8 ± 0.1 million ponds. The 2005
pond estimate in Prairie and Parkland Canada was 3.9 ± 0.2 million. This was a 56% increase relative to
last year’s estimate of 2.5 ± 0.1 million ponds and 17% higher than the long-term average of 3.3 ± 0.3
million ponds. The 2005 pond estimate for the northcentral U.S. (1.5 ± 0.1 million) was similar to last
year’s estimate (Fig.1). The projected mallard fall flight index was 9.3 ± 0.1 million, similar to the 2004
estimate of 9.4 ± 0.1 million birds. The eastern survey area was restratified, and is now composed of strata
51-72. Mergansers (red-breasted [Mergus serrator], common [M. merganser], and hooded [Lophodytes
cucullatus;]; -25%), mallards (-36%), American black ducks (A. rubripes, -24%), and green-winged teal (-
46%) were all below their 2004 estimates. Ring-necked ducks (Aythya collaris) and goldeneyes (common
[Bucephala clangula] and Barrow’s [B. islandica]) were similar to their 2004 estimates. No species in the
eastern survey area differed from their long-term averages.
This section summarizes the most recent
information about the status of North American duck
populations and their habitats in order to facilitate
development of harvest regulations in the U.S. The
U.S. Fish and Wildlife Service and its partners
conduct a variety of surveys to collect information on
ducks. The annual status of these populations is
assessed using databases resulting from these
surveys, which include estimates of the size of
breeding populations, production, and harvest. This
report details abundance estimates and production
outlooks; harvest survey results are discussed in
separate reports. The data and analyses were the
most current available when this report was written.
Future analyses may yield slightly different results as
databases are updated and new analytical
procedures become available.
METHODS
Breeding Population and Habitat Survey
Federal, provincial, and state agencies conduct
surveys each spring to estimate the size of breeding
populations and to evaluate the condition of the
habitats. These surveys are conducted using fixed-wing
aircraft and helicopters, and cover over 2.0
million square miles that encompass principal
breeding areas of North America. The traditional
survey area (strata 1-18, 20-50, and 75-77)
comprises parts of Alaska, Canada, and the
northcentral U.S., and includes approximately 1.3
million square miles (Appendix C). The eastern
survey area (strata 51-72) includes parts of Ontario,
Quebec, Labrador, Newfoundland, Nova Scotia,
Prince Edward Island, New Brunswick, New York,
and Maine, covering an area of approximately 0.7
million square miles.
In Prairie and Parkland Canada and the north-central
U.S., aerial waterfowl counts are corrected
annually for visibility bias by conducting ground
counts. In the northern portions of the traditional
survey area and the eastern survey area, duck
estimates are adjusted using visibility correction
factors derived from a comparison of airplane and
helicopter counts. Annual estimates of duck
5
abundance are available since 1955 for the
traditional survey area and since 1996 for all
strata (except 57 and 58) in the eastern survey
area. However, portions of the eastern survey
area have been surveyed since 1990. In the
traditional survey area, estimates of pond
abundance in Prairie and Parkland Canada are
available since 1961 and in the northcentral U.S.
since 1974. Several provinces and states also
conduct breeding waterfowl surveys using various
methods; some have survey designs that allow
calculation of measures of precision for their
estimates. Information about habitat conditions
was supplied primarily by biologists working in the
survey areas. However, much ancillary weather
information was obtained from agricultural and
weather internet sites (see references). Unless
otherwise noted, the alpha level (P value) for
determining statistical significance was set at 0.1;
actual P values are given in tables along with
wetland and waterfowl estimates.
Since 1990 the U.S. Fish and Wildlife Service
(USFWS) has conducted aerial transect surveys
using fixed-wing aircraft in eastern Canada and
the northeast U.S., similar to those used in the
mid-continent, for estimating waterfowl
abundance. Additionally, the Canadian Wildlife
Service (CWS) has conducted a helicopter-based
aerial plot survey in core nesting areas of
American black ducks in Ontario, Quebec, and the
Atlantic Provinces. Historically, data from these
surveys were analyzed separately, despite
geographic overlap in survey coverage. In 2004,
the USFWS and Canadian Wildlife Service (CWS)
agreed to integrate the two surveys, produce
composite estimates from both sets of survey
data, and expand the geographic scope of the
survey in eastern North America.
As a result, waterfowl population estimates for
eastern North America will no longer be produced
solely on the basis of USFWS-collected data, but
will be based on both USFWS and CWS data.
Estimates of populations in eastern North America
(strata 51-72) in this report are composite
estimates based on data from the CWS and
USFWS surveys. For strata containing both CWS
and USFWS data (51, 52, 63, 64, 66, and 68),
visibility-adjusted USFWS data were combined
with plot data; single survey results were used as
the estimates for strata containing only one source
of information (69, 53, 54, 55, 56, 62, 65, and 67
for transects; 70, 71, and 72 for plots). Strata 57
and 58 were not consistently surveyed over the
interval 1999-2005, and were not included in
population totals for the eastern area. Estimates
for these 2 strata will be incorporated in future
reports. For widely-distributed species, (American
black ducks, mallards, green-winged teal,
merganser, ring-necked duck, and goldeneye),
composite estimates of population size were
constructed using a hierarchical model, in which
change is modeled using a linear model that
includes survey and transect/plot effects (e.g.,
Link and Sauer 2002). Area-weighted,
exponentiated year effects (or averaged year
effects, when both surveys were conducted in a
stratum) were used as estimates of total indicated
birds in each stratum (Royle et al. 2002).
Additional technical issues must be resolved for
species with patchy distributions in the eastern
survey area (bufflehead [B. albeola], scoters
[Melanitta spp.], American wigeon, and scaup);
therefore estimates for these species are not
presented in this report.
To produce a consistent index in the Eastern
Survey Area for American black ducks, total
indicated birds were calculated using the CWS
method of scaling observed pairs. Observed
black duck pairs were scaled by 1.5 rather than
the 1.0 scaling traditionally applied by the
USFWS. The CWS scaling is based on sex-specific
observations collected during the CWS
survey in eastern Canada which indicate that
approximately 50% of black duck pair
observations are actually 2 drakes. For other
species, the standard USFWS definition of total
indicated birds was used. Procedures for deriving
composite estimates from surveys and defining
total indicated birds are presently undergoing
review and evaluation by CWS and USFWS
personnel.
Another notable change relative to previous
reports on waterfowl status in eastern North
America is that estimates of population
abundance are presented back only to 1999.
Additional work must be done to reconstruct a
composite time-series for the entire period of
record for these surveys. Finally, we have taken
initial steps toward re-stratification in eastern
Canada (Fig. 1). Taken together, changes in
indices, analytical procedures, geographic
stratification, and the area sampled by the
composite surveys mean that these revised
survey results for eastern North America are not
directly comparable with results presented in
previous reports.
We anticipate other changes to survey design
and analysis for eastern North America during the
coming years, and view the composite estimates
for strata 51 to 72 as the first step toward a fully
integrated survey. They likely will change in the
6
near future as the USFWS and CWS agree upon
the final survey design and analytical methods.
Production and Habitat Survey
For the past two years, we had no traditional July
Production Survey to verify the early predictions of
our biologists in the field, due to severe budget
constraints within the migratory bird program.
However, the pilot-biologists responsible for several
survey areas (southern Alberta, southern
Saskatchewan southern Manitoba, the Dakotas, and
Montana) returned in early July for a brief flight over
representative portions of their areas as a rough
assessment of habitat changes since May and
resultant duck production. This information, along
with reports from local biologists in the field, helped
us formulate our overall perspective on duck
production this year.
Total Duck Species Composition
In the traditional survey area, our estimate of total
ducks excludes scoters, eiders (Somateria and
Polysticta spp.), long-tailed ducks (Clangula
hyemalis), mergansers, and wood ducks (Aix
sponsa), because the traditional survey area does
not include a large portion of their breeding range.
However, mergansers breed throughout a large
portion of the eastern survey area. Therefore, the
total-duck species composition in the eastern survey
area includes these species. Estimates for
canvasbacks, redheads, and ruddy ducks (Oxyura
jamaicensis) are excluded from the eastern total-duck
estimate because these species are rare
breeders in this region. Wood ducks also are not
included in the total-duck estimate for the eastern
survey area, even though this species breeds over
much of the region, as their wooded habitats make
them difficult to detect from the air.
Mallard Fall-flight Index
The mallard fall-flight index is a prediction of the
size of the fall abundance of mallards originating
from the mid-continent region of North America.
For management purposes, the mid-continent
population is composed of mallards originating
from the traditional survey area, as well as
Michigan, Minnesota, and Wisconsin. The index is
based on the mallard models used for Adaptive
Harvest Management, and considers breeding
population size, habitat conditions, adult summer
survival, and projected fall age ratio (young/adult).
The projected fall age ratio is predicted from a
model that depicts how the age ratio varies with
changes in spring population size and pond
abundance. The fall-flight index represents a
weighted average of the fall flights predicted by
the four alternative models of mallard population
dynamics used in Adaptive Harvest Management
(U. S. Fish and Wildlife Service 2005).
RESULTS AND DISCUSSION
2004 in Review
Most of the U.S. and Canadian prairies were
much drier in May 2004 than in May 2003, which
was reflected in the pond counts for these regions.
For the U.S. Prairies and Canadian Prairie and
Parkland combined, the May pond estimate was
3.9 ± 0.2 million, which was 24% lower than the
2003 estimate and 19% below the long-term
average. Pond numbers in both Canada (2.5 ± 0.1
million) and the U. S. (1.4 ± 0.1 million) were
below their 2003 estimates (-29% in Canada and
-16% in the U.S). Canadian ponds were 25%
below their long-term average.
The good water conditions that prevailed in
2003 on the short-grass prairies of southern
Alberta and Saskatchewan did not continue into
2004, and habitat in these areas went from good
to fair or poor. Habitat in southern Manitoba
ranged from poor in the east-central to good in the
west, with conditions similar to those of previous
years. In the Dakotas, a slow drying trend
continued, and much of eastern South Dakota
was in poor condition. Conditions in the Dakotas
were better to the north, and eastern Montana
was a mosaic of poor to good conditions. Although
prairie areas received considerable moisture from
snow, including a late-spring snowstorm in
southern regions, the snowmelt was absorbed by
the parched ground. Furthermore, snow and cold
during May probably adversely affected early
nesters and young broods. Many prairie areas
received abundant water after May surveys, but it
likely did not alleviate dry conditions, because this
precipitation also soaked into the ground.
Therefore, overall expected production from the
prairies was only poor to fair in 2004.
Spring thaw was exceptionally late in 2004 in
the Northwest Territories, northern Alberta,
northern Saskatchewan, and northern Manitoba.
This meant that birds that over-flew the prairies
due to poor conditions encountered winter-like
conditions in the bush, and nesting may have
been curtailed. This was especially true for early-nesting
species like mallards and northern pintails;
late nesters likely had better success. Overall, the
7
bush regions were only fair to marginally good for
production due to this late thaw. However, Alaska
birds likely produced well due to excellent habitat
conditions there. Areas south of the Brooks Range
experienced a widespread, record-setting early
spring breakup, and flooding of nesting areas was
minimal.
Breeding habitat conditions in 2004 were
generally good to excellent in the eastern U.S.
and Canada. Although spring was late in most
areas, it was thought nesting was not significantly
affected because of abundant spring rain and mild
temperatures during and following nesting.
Production in the east was normal in Ontario and
the Maritimes, and slightly below normal in
Quebec.
In the traditional survey area, the total duck
population estimate (excluding scoters, eiders,
long-tailed ducks, mergansers, and wood ducks)
was 32.2 ± 0.6 million birds, 11% below the 2003
estimate of 36.2 ± 0.7 million birds, and 3% below
the long-term (1955-2003) average. In the eastern
Dakotas, total duck numbers were similar to the
previous year’s estimate, and remained 29%
above the long-term average. Counts in southern
Alberta were also similar to last year’s, and
remained 42% below the long-term average. The
total-duck estimate decreased 38% relative to
2003 in southern Saskatchewan and was 22%
below the long-term average. Counts in central
and northern Alberta, northeast British Columbia
and the Northwest Territories were similar to the
previous year's but below the long-term average.
Counts in the northern Saskatchewan--northern
Manitoba--western Ontario area, and the Alaska--
Yukon Territory--Old Crow Flats region were both
similar to 2003 estimates, but above their long-term
averages. Total duck counts in the southern
Manitoba region and the western Dakotas--
eastern Montana region were similar to 2003
estimates and to long-term averages. The 2004
total duck population estimate for the eastern
survey area was 3.9 ± 0.3 million birds. This
estimate was similar to the previous year's (3.6 ±
0.3 million birds), and to the 1996-2003 average.
In British Columbia, California, northeastern U.S.,
Oregon, and Wisconsin, measures of precision for
survey estimates are provided. In 2004, total duck
abundance decreased by 23% in California relative to
2003, and was similar to 2003 estimates in British
Columbia, Wisconsin, Oregon, and the northeastern
U.S. The total duck estimate was down 31% in
California and 16% in Oregon relative to the long-term
average. In Wisconsin, total ducks were 58%
above their long-term average. In British Columbia
and the northeastern U.S., 2004 total duck estimates
were similar to their long-term averages. Of the
states without measures of precision for total duck
numbers, estimates of total ducks increased in
Nevada, Minnesota, and Michigan relative to 2003,
but estimates decreased in Nebraska and
Washington compared to the previous year.
Weather and habitat conditions during the
summer months can influence waterfowl
production. Good wetland conditions increase
renesting effort and brood survival. In general,
2004 habitat conditions stabilized or improved
over most of the traditional survey area between
May and July. While there were no formal July
surveys flown in 2004, experienced crew leaders
in Montana and the western Dakotas, the eastern
Dakotas, southern Alberta, and southern
Saskatchewan returned to their May survey areas
in early July to qualitatively assess habitat
changes between May and July. Biologists from
other survey areas communicated with local
biologists to get their impressions of 2004
waterfowl production and monitored weather
conditions. Habitat in some portions of the
prairies, particularly in the Dakotas and Alberta,
improved between May and July because of
abundant summer rain. However, there were few
birds in these areas because many had left the
prairies in the early spring when habitat conditions
were dry. Therefore, the production potential from
most prairie areas ranged from poor to good and
was generally worse than in 2003. Habitat
conditions in the northern and eastern areas are
more stable because of the deeper, more
permanent water bodies there. Because
temperatures were so cold in May of 2004, the
outlook for production from these areas was fair in
the northern Prairie Provinces, and good to
excellent in the eastern survey area.
2005 Breeding Habitat Conditions,
Populations, and Production
Overall Habitat and Population Status
Habitat conditions at the time of the survey in
May 2005 were variable, with some areas
improved relative to last year and others
remaining or becoming increasingly dry. The total
May pond estimate (Prairie and Parkland Canada
and the northcentral U.S. combined) was 5.4 ± 0.2
million ponds. This was 37% greater than last
year’s estimate of 3.9 ± 0.2 million ponds and 12%
higher than the long-term average of 4.8 ± 0.1
million ponds. Habitat in the surveyed portion of
the U.S. prairies was in fair to poor condition due
to a dry fall, winter, and early spring and warm
8
Table 1. Estimated number (in thousands) of May ponds in portions of prairie and parkland Canada and the northcentral U.S.
Change from 2004 Change from LTA
Survey Area 2005 2004 % P LTAa % P
Prairie Canada
S. Alberta 750 511 +47 0.007 721 +4 0.689
S. Saskatchewan 2415 1,461 +65 <0.001 1,953 +24 0.009
S. Manitoba 755 541 +40 0.001 671 +13 0.101
Subtotal 3,921 2,513 +56 <0.001 3,346 +17 0.004
Northcentral U.S.
Montana and western Dakotas 663 597 +11 0.354 524 +27 0.016
Eastern Dakotas 798 810 -1 0.913 1,000 -20 <0.001
Subtotal 1,461 1,407 +4 0.678 1,524 -4 0.440
Grand Total 5,381 3,920 +37 <0.001 4,813 +12 0.008
aLong-term average. Prairie and parkland Canada, 1961-2004; northcentral U.S. and Grand Total, 1974-2004.
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
10.0
1960 1965 1970 1975 1980 1985 1990 1995 2000 2005
Millions
Northcentral U.S.
Prairie Canada
Total
Year
Figure 1. Number of ponds in May and 95% confidence intervals in prairie and parkland Canada and the northcentral U.S.
9
winter temperatures. Nesting habitat was
particularly poor in South Dakota because of
below average precipitation resulting in degraded
wetland conditions and increased tilling and
grazing of wetland margins. Birds may have over-flown
the state for wetter conditions to the north.
Water levels and upland nesting cover were
relatively better in North Dakota and eastern
Montana, and wetland conditions in these regions
improved markedly during June following the
survey, with the onset of well-above average
precipitation.
The 2005 pond estimate for north-central U.S.
(1.5 ± 0.1 million) was similar to last year’s
estimate (Fig. 2). The prairies of southern Alberta
and southwestern Saskatchewan were also quite
dry in early May. 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 prevent overflight. This heavy rain
likely benefited late-nesting species and improved
renesting. Record high rains flooded the lower
elevation prairie areas of central Manitoba during
April, producing fair or poor nesting conditions for
breeding waterfowl. In contrast, the Canadian
Parklands were much improved compared to last
year, due to several years of improving nesting
cover and above-normal precipitation last fall and
winter. These areas were in good-to-excellent
condition at the start of the survey and remained
so into July. Overall, the May pond estimate in
Prairie and Parkland Canada was 3.9 ± 0.2
million. This was a 56% increase over last year’s
estimate of 2.5 ± 0.1 million ponds and 17%
higher than the long-term average of 3.3 ± 0.3
million ponds.
Portions of northern Manitoba and northern
Saskatchewan also experienced flooding,
resulting in only fair conditions for breeding
waterfowl. In contrast, most of the Northwest
Territories was in good condition due to adequate
water and a timely spring break-up that made
habitat available to early-nesting species.
However, dry conditions in eastern parts of the
Northwest Territories and northern Alberta
resulted in low water levels in lakes and ponds
and the complete drying of some wetlands.
Therefore, habitat was also classified as fair in
these areas. For the most part, habitats in Alaska
were in excellent condition, with an early spring
and good water levels, except for a few flooded
river areas and on the North Slope, where spring
was late.
In the Eastern Survey Area (strata 51-72),
habitat conditions were generally good due to
adequate water and relatively mild spring
temperatures. Exceptions were the coast of
Maine and the Atlantic Provinces, where May
temperatures were cool and some flooding
occurred along the coast and major rivers. Also,
below-normal precipitation left some habitat in fair
to poor condition in southern Ontario. However,
precipitation in southern Ontario after survey
completion improved habitat conditions in that
region.
In the traditional survey area, the total duck
population estimate (excluding scoters, eiders,
long-tailed ducks, mergansers, and wood ducks)
was 31.7 ± 0.6 million birds, similar to last year’s
estimate of 32.2 ± 0.6 million birds, and 5% below
the long-term (1955-2004) average (Table 2,
Appendix G). In the eastern Dakotas, total duck
numbers were 14% below last year’s estimate, but
remained 10% above the long-term average.
Counts in southern Alberta were 27% higher than
those last year, but remained 26% below the long-term
average. The total-duck estimate increased
38% relative to last year in southern
Saskatchewan and was 9% above the long-term
average. Total duck estimates in central and
northern Alberta, northeastern British Columbia
and the Northwest Territories were 20% below last
year's estimate and 35% below the long-term
average (Table 2). Counts in the western Ontario--
northern Saskatchewan--northern Manitoba area,
and the western Dakotas--Eastern Montana area
were 21% and 20% below 2004 estimates,
respectively, and 10% and 20% below their long-term
averages. In the Alaska--Yukon Territory--
Old Crow Flats region the total duck estimate was
similar to that of 2004, but remained 45% above
its long-term average. Total duck counts in
southern Manitoba remained unchanged from the
2004 estimate and the long-term average
Several states and provinces conduct breeding
waterfowl surveys in areas outside the geographic
extent of the Waterfowl Breeding Population and
Habitat Survey of the USFWS and CWS. In British
Columbia, California, northeastern U.S., Oregon, and
Wisconsin, measures of precision for survey
estimates are available. Total duck abundance
increased by 49% in California relative to 2004, and
was similar to 2004 in British Columbia, Wisconsin,
and the northeastern U.S. The total duck estimate
was similar to the long-term average in California. In
Wisconsin, total ducks were 73% above their long-
10
Table 2. Total ducka breeding population estimates (in thousands).
Change from 2004 Change from LTA
Region 2005 2004 % P LTAb % P
Traditional Survey Area
Alaska - Yukon Territory
- Old Crow Flats 5,114 5,456 -6 0.194 3,519 +45 <0.001
C. & N. Alberta - N.E. British Columbia
- Northwest Territories 4,713 5,882 -20 0.001 7,202 -35 <0.001
N. Saskatchewan - N. Manitoba
- W. Ontario 3,223 4,085 -21 0.007 3,564 -10 0.099
S. Alberta 3,178 2,499 +27 0.002 4,305 -26 <0.001
S. Saskatchewan 7,967 5,783 +38 <0.001 7,336 +9 0.024
S. Manitoba 1,627 1,474 +10 0.172 1,542 +5 0.287
Montana and Western Dakotas 1,290 1,615 -20 0.006 1,620 -20 <0.001
Eastern Dakotas 4,623 5,370 -14 0.022 4,193 +10 0.067
Total 31,735 32,164 -1 0.593 33,281 -5 0.006
Other Regions
British Columbia c 6 7 -15 0.530 6 -14 0.458
California 615 413 +49 0.010 599 +3 0.820
Northeastern U.S. d 1,416 1,417 -1 0.997 143 -1 0.907
Oregon 225 245 -8 0.377 302 -25 <0.001
Wisconsin 724 651 +11 0.462 420 +73 <0.001
a Excludes eider, long-tailed duck, wood duck, scoter, and merganser in traditional survey area; excludes eider, long-tailed duck, wood duck, redhead, canvasback and ruddy
duck in eastern survey area; species composition for other regions varies.
b Long-term average. Traditional survey area=1955-2004; years for other regions vary (see Appendix E).
c Index to waterfowl use in prime waterfowl producing regions of the province. Estimates do not match those from previous reports because of change in analytical method.
d Includes all or portions of CT, DE, MD, MA, NH, NJ, NY, PA, RI, VT, and VA.
e Not estimable from current survey.
11
Table 3. Mallard breeding population estimates (in thousands).
Change from 2004 Change from LTA
Region 2005 2004 % P LTAb % P
Traditional Survey Area
Alaska - Yukon Territory
- Old Crow Flats 703 811 -13 0.199 350 +101 <0.001
C. & N. Alberta - N.E. British Columbia
- Northwest Territories 533 776 -31 0.025 1,097 -51 <0.001
N. Saskatchewan - N. Manitoba
- W. Ontario 937 1,283 -27 0.143 1,163 -19 0.165
S. Alberta 671 600 +12 0.460 1,107 -39 <0.001
S. Saskatchewan 1,729 1,609 +7 0.515 2,079 -17 0.007
S. Manitoba 455 393 +16 0.194 377 +21 0.054
Montana and Western Dakotas 387 495 -22 0.160 502 -23 0.017
Eastern Dakotas 1,340 1,456 -8 0.520 836 +60 <0.001
Total 6,755 7,425 -9 0.092 7,510 -10 0.008
Eastern Survey Area
Other Regions
British Columbia b 1 1 -16 0.436 1 -22 0.064
California 318 262 +21 0.341 372 -15 0.275
Michigan 230 329 -30 0.075 428 -46 <0.001
Minnesota 239 375 -36 0.033 223 +7 d
Northeastern U.S. c 754 806 -6 0.483 804 -6 0.367
Oregon 83 92 -10 0.342 113 -26 <0.001
Wisconsin 317 229 +38 0.087 175 +81 0.001
a Long-term average. Traditional survey area=1955-2004; eastern survey area=1999-2004; years for other regions vary (see Appendix E).
b Index to waterfowl use in prime waterfowl producing regions of the province. Estimates do not match those from previous reports because of change in analytical method.
c Includes all or portions of CT, DE, MD, MA, NH, NJ, NY, PA, RI, VT, and VA.
d Value for test statistic was not available.
12
Figure 2. Breeding population estimates, 95% confidence intervals, and North American Waterfowl Management
Plan population goal (dashed line) for selected species in the traditional survey area (strata 1-18, 20-50, 75-77).
Mallard
0
2
4
6
8
10
12
14
1955 1965 1975 1985 1995 2005
Year
Millions
American wigeon
0
1
2
3
4
5
1955 1965 1975 1985 1995 2005
Year
Millions
Gadwall
0
1
2
3
4
5
1955 1965 1975 1985 1995 2005
Year
Millions
Blue-winged teal
0
1
2
3
4
5
6
7
8
9
1955 1965 1975 1985 1995 2005
Year
Millions Green-winged teal
0
1
2
3
4
1955 1965 1975 1985 1995 2005
Year
Millions
Total ducks
20
25
30
35
40
45
50
1955 1965 1975 1985 1995 2005
Year
Millions
13
Figure 2 (continued).
Northern pintail
0
2
4
6
8
10
12
1955 1965 1975 1985 1995 2005
Year
Millions
Canvasback
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1955 1965 1975 1985 1995 2005
Year
Millions
Redhead
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1955 1965 1975 1985 1995 2005
Year
Millions
Scaup
0
2
4
6
8
10
1955 1965 1975 1985 1995 2005
Year
Millions
Northern shoveler
0
1
2
3
4
5
1955 1965 1975 1985 1995 2005
Year
Millions
American black duck
(Mid-winter survey)
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
1955 1965 1975 1985 1995 2005
Year
Millions
Mississippi Flyway
Atlantic Flyway
Total
14
term average. In British Columbia, California, and the
northeastern U.S., total duck estimates were similar
to their long-term averages. Of the states without
measures of precision for total duck numbers,
estimates of total ducks decreased in Nevada,
Minnesota, Washington, Oregon, and Michigan, and
increased in Nevada, relative to 2004.
Trends and annual breeding population
estimates for 10 principal duck species from the
traditional survey area are provided in Figure 2,
Tables 3-12, and Appendix F. Mallard abundance
was 6.8 ± 0.3 million, which was 9% lower than
last year’s estimate of 7.4 ± 0.3 million, and 10%
lower than the long-term average (Table 3).
Mallard numbers dropped 31% relative to last
year’s estimate in the central and northern
Alberta--northeastern British Columbia--Northwest
Territories survey area, but remained unchanged
relative to 2004 in all other survey areas. Mallard
numbers remained 101% above their long-term
average in the Alaska--Yukon Territory--Old Crow
Flats region, and were 60% and 21% higher than
the long-term averages in the eastern Dakotas
and southern Manitoba, respectively. Mallards
were 17% below their long-term average in
southern Saskatchewan, and 23% below in
Montana and the western Dakotas. Mallard
estimates for the central and northern Alberta--—
northeastern British Columbia--Northwest
Territories were also below their long-term
average (-51%). In the northern Saskatchewan--
northern Manitoba--western Ontario survey area
the mallard estimate was similar to its long-term
average. In other areas where surveys are
conducted and measures of precision for estimates
are provided (the same states as for total ducks, as
well as Michigan and Minnesota), mallard abundance
remained unchanged from 2004, except for Michigan
(-30%) and Wisconsin (+38%). Mallard estimates
were below the long-term average in Michigan,
British Columbia, and Oregon, similar to the long-term
average in California, and the northeastern U.
S., and above it in Wisconsin. In Nebraska, Nevada
and Washington, estimates of precision are
unavailable, but mallard counts were down relative to
last year’s in Nevada, higher than last year's counts
in Nebraska, and were similar in Washington.
Blue-winged teal abundance was estimated at
4.6 ± 0.2 million birds, 13% higher than last year’s
estimate of 4.1 ± 0.2 million birds and similar to
the 1955-2004 average. Of the other duck
species, gadwall (2.2 ± 0.1 million) dropped 16%
relative to 2004 but remained 30% above their
long-term average. American wigeon (2.2 ± 0.1
million) and scaup (3.4 ± 0.2 million) were similar
to their 2004 estimates, but were 15% and 35%
below their long-term averages, respectively.
Green-winged teal (2.2 ± 0.1 million) were also
similar to their 2004 estimate, but were 16%
higher than their long-term average. Northern
pintails (2.6 ± 0.2 million) increased by 17%
relative to last year, but remained 38% below their
long-term average. The northern shoveler
estimate was 28% higher than last year’s, and
67% higher than the long-term average. Redhead
(0.6 ± 0.1 million), and canvasback (0.5 ± 0.1
million) estimates were similar to their 2004
estimates and long-term averages.
Populations of all the six species in the eastern
survey area that we reported were similar to their
1999-2004 estimates (Table 13, Appendix H).
Mergansers, mallards, American black ducks, and
green-winged teal were 25%, 36%, 24% and 46%
below their 2004 estimates. The ring-necked duck
and goldeneye estimates were similar to those of
2004.
The longest time-series of data available to assess
the status of the American black duck (Anas
rubripes) is provided by the Midwinter surveys
conducted in January in states of the Atlantic and
Mississippi Flyways. The trend in the winter index for
the total population is depicted in Figure 2. Measures
of precision are not available for the midwinter
surveys. Midwinter counts of American black ducks
(203,900 in both flyways combined) declined relative
to 2004 counts. This was 10% lower than the 2004
index of 226,700, and 25% lower than the 10-year
mean (272,600). In the Atlantic Flyway, the midwinter
index of 184,100 decreased 11% from 206,400 in
2004, and was 18% below the most recent 10-year
mean (225,000). In the Mississippi Flyway, the
American black duck mid-winter index decreased 2%
from 20,300 in 2004 to 19,900, which is 58% below
the 10-year mean (47,600). A shorter time series for
assessing change in American black duck population
status is provided by the breeding waterfowl surveys
conducted by the USFWS and CWS in the eastern
survey area. In the eastern survey area, the 2004
estimate for breeding American black ducks
(827,000) was down 24% compared to last year’s
estimate (1,093,000) but similar to the 1999-2004
average (1,002,000).
Trends in wood duck populations are monitored by
the North American Breeding Bird Survey (BBS), a
series of roadside routes surveyed during May and
June each year. Wood ducks are encountered with
low frequency along BBS routes, limiting the amount
and quality of available information for analysis
(Sauer and Droege 1990). However, the BBS
provides the only long-term indices of this species'
regional populations. Trend analysis suggests that
wood duck numbers increased 3.8% per year over
15
Figure 3. Median population size and credibility intervals for 6 species in the Eastern survey area (strata 51-72).
Mergansers
0
500
1000
1500
2000
2500
1998 1999 2000 2001 2002 2003 2004 2005 2006
Year
Thousands
Mallard
0
200
400
600
800
1000
1200
1998 1999 2000 2001 2002 2003 2004 2005 2006
Year
Thousands
American black duck
0
200
400
600
800
1000
1200
1400
1600
1800
1998 1999 2000 2001 2002 2003 2004 2005 2006
Year
Thousands
Green-winged teal
0
500
1000
1500
2000
2500
3000
1998 1999 2000 2001 2002 2003 2004 2005 2006
Year Thousands
Ring-necked duck
0
500
1000
1500
2000
2500
3000
3500
1998 1999 2000 2001 2002 2003 2004 2005 2006
Year
Thousands
Goldeneyes
0
500
1000
1500
2000
2500
3000
3500
1998 1999 2000 2001 2002 2003 2004 2005 2006
Year
Thousands
16
Table 4. Gadwall breeding population estimates (in thousands) for regions in the traditional survey area.
Change from 2004 Change from LTA
Region 2005 2004 % P LTA % P
Alaska-Yukon Territory
– Old Crow Flats 3 2 +42 0.734 2 +43 0.705
C. & N. Alberta – N.E. British Columbia
- Northwest Territories 77 138 -44 0.083 46 +66 0.050
N. Saskatchewan- N. Manitoba
- W. Ontario 19 22 -16 0.772 28 -32 0.133
S. Alberta 338 290 +17 0.492 308 +10 0.612
S. Saskatchewan 723 752 -4 0.847 553 +31 0.052
S. Manitoba 120 148 -18 0.362 65 +84 <0.001
Montana and western Dakotas 187 205 -9 0.614 194 -4 0.797
Eastern Dakotas 712 1,033 -31 0.006 486 +46 0.001
Total 2,179 2,590 -16 0.052 1,683 +30 <0.001
Table 5. American wigeon breeding population estimates (in thousands) for regions in the traditional survey area.
Change from 2004 Change from LTA
Region 2005 2004 % P LTA % P
Alaska-Yukon Territory
– Old Crow Flats 873 897 -3 0.790 504 +73 <0.001
C. & N. Alberta – N.E. British Columbia
- Northwest Territories 583 565 +3 0.889 919 -36 0.002
N. Saskatchewan- N. Manitoba
- W. Ontario 174 149 +17 0.568 254 -31 0.013
S. Alberta 125 117 +8 0.728 300 -58 <0.001
S. Saskatchewan 294 128 +130 0.002 428 -31 0.006
S. Manitoba 34 3 +893 0.002 62 -45 0.006
Montana and western Dakotas 67 66 +2 0.926 110 -39 <0.001
Eastern Dakotas 73 56 +30 0.405 48 +53 0.114
Total 2,225 1,981 +12 0.177 2,624 -15 0.005
17
Table 6. Green-winged teal breeding population estimates (in thousands) for regions in the traditional survey area.
Change from 2004 Change from LTA
Region 2005 2004 % P LTA % P
Alaska-Yukon Territory
– Old Crow Flats 713 819 -13 0.289 351 +103 <0.001
C. & N. Alberta – N.E. British Columbia
- Northwest Territories 437 835 -48 0.002 759 -42 <0.001
N. Saskatchewan- N. Manitoba
- W. Ontario 310 375 -17 0.262 195 +59 0.002
S. Alberta 159 98 +61 0.138 195 -18 0.291
S. Saskatchewan 359 124 +189 <0.001 227 +58 0.027
S. Manitoba 55 27 +103 0.007 52 +7 0.686
Montana and western Dakotas 83 104 -20 0.395 39 +113 0.008
Eastern Dakotas 42 79 -47 0.079 45 -8 0.742
Total 2,157 2,461 -12 0.114 1,861 +16 0.021
Table 7. Blue-winged teal breeding population estimates (in thousands) for regions in the traditional survey area.
Change from 2004 Change from LTA
Region 2005 2004 % P LTA % P
Alaska-Yukon Territory
– Old Crow Flats 3 2 +25 0.876 1 +105 0.626
C. & N. Alberta – N.E. British Columbia
- Northwest Territories 247 401 -38 0.116 271 -9 0.704
N. Saskatchewan- N. Manitoba
- W. Ontario 139 60 +130 0.102 268 -48 0.007
S. Alberta 649 360 +80 0.009 608 +7 0.665
S. Saskatchewan 1,597 1,155 +38 0.026 1,210 +32 0.002
S. Manitoba 339 282 +20 0.206 383 -12 0.207
Montana and western Dakotas 286 320 -10 0.508 263 +9 0.467
Eastern Dakotas 1,325 1,493 -11 0.427 1,496 -11 0.275
Total 4,586 4,073 +13 0.126 4,499 +2 0.720
18
Table 8. Northern shoveler breeding population estimates (in thousands) for regions in the traditional survey area.
Change from 2004 Change from LTA
Region 2005 2004 % P LTA % P
Alaska-Yukon Territory
– Old Crow Flats 666 643 +4 0.806 259 +158 <0.001
C. & N. Alberta – N.E. British Columbia
- Northwest Territories 213 247 -14 0.554 213 0 0.992
N. Saskatchewan- N. Manitoba
- W. Ontario 29 33 -13 0.683 43 -34 0.016
S. Alberta 548 385 +42 0.133 356 +54 0.018
S. Saskatchewan 1,314 784 +68 0.001 634 +107 <0.001
S. Manitoba 211 143 +47 0.176 105 +100 0.004
Montana and western Dakotas 148 200 -26 0.204 149 -1 0.959
Eastern Dakotas 464 377 +23 0.212 388 +19 0.170
Total 3,591 2,810 +28 0.001 2,149 +67 <0.001
Table 9. Northern pintail breeding population estimates (in thousands) for regions in the traditional survey area.
Change from 2004 Change from LTA
Region 2005 2004 % P LTA % P
Alaska-Yukon Territory
– Old Crow Flats 905 927 -2 0.856 913 -1 0.939
C. & N. Alberta – N.E. British Columbia
- Northwest Territories 108 193 -44 0.073 384 -72 <0.001
N. Saskatchewan- N. Manitoba
- W. Ontario 8 10 -18 0.672 42 -80 <0.001
S. Alberta 282 161 +75 0.049 730 -61 <0.001
S. Saskatchewan 858 474 +81 0.009 1,225 -30 <0.001
S. Manitoba 68 40 +71 0.042 113 -40 <0.001
Montana and western Dakotas 75 132 -43 0.031 273 -73 <0.001
Eastern Dakotas 256 247 +4 0.860 463 -45 <0.001
Total 2,561 2,185 +17 0.079 4,142 -38 <0.001
19
Table 10. Redhead breeding population estimates (in thousands) for regions in the traditional survey area.
Change from 2004 Change from LTA
Region 2005 2004 % P LTA % P
Alaska-Yukon Territory
– Old Crow Flats <1 2 -91 0.044 1 -84 <0.001
C. & N. Alberta – N.E. British Columbia
- Northwest Territories 49 73 -33 0.304 38 +30 0.530
N. Saskatchewan- N. Manitoba
- W. Ontario 13 31 -57 0.136 28 -53 <0.001
S. Alberta 91 79 +16 0.648 117 -22 0.170
S. Saskatchewan 226 131 +72 0.02 189 +19 0.251
S. Manitoba 98 102 -4 0.900 71 +37 0.338
Montana and western Dakotas 3 25 -89 0.102 10 -70 0.002
Eastern Dakotas 112 161 -31 0.102 170 -34 0.002
Total 592 605 -2 0.858 625 -5 0.536
Table 11. Canvasback breeding population estimates (in thousands) for regions in the traditional survey area.
Change from 2004 Change from LTA
Region 2005 2004 % P LTA % P
Alaska-Yukon Territory
– Old Crow Flats 95 161 -41 0.207 91 +4 0.887
C. & N. Alberta – N.E. British Columbia
- Northwest Territories 98 109 -11 0.768 72 +35 0.416
N. Saskatchewan- N. Manitoba
- W. Ontario 39 50 -21 0.578 56 -30 0.253
S. Alberta 43 50 -15 0.758 64 -33 0.104
S. Saskatchewan 162 121 +34 0.181 183 -11 0.425
S. Manitoba 48 70 -32 0.344 56 -15 0.518
Montana and western Dakotas 5 12 -60 0.046 8 -39 0.095
Eastern Dakotas 31 44 -28 0.275 33 -5 0.817
Total 521 617 -16 0.247 563 -8 0.433
20
Table 12. Scaup (greater and lesser combined) breeding population estimates (in thousands) for regions in the traditional
survey area.
Change from 2004 Change from LTA
Region 2005 2004 % P LTA % P
Alaska-Yukon Territory
– Old Crow Flats 961 982 -2 0.865 914 +5 0.593
C. & N. Alberta – N.E. British Columbia
- Northwest Territories 1,361 1,624 -16 0.232 2,653 -49 <0.001
N. Saskatchewan- N. Manitoba
- W. Ontario 349 582 -40 <0.001 592 -41 <0.001
S. Alberta 127 124 +2 0.948 358 -65 <0.001
S. Saskatchewan 381 185 +106 0.008 417 -9 0.595
S. Manitoba 60 31 +91 0.019 137 -56 <0.001
Montana and western Dakotas 16 28 -41 0.309 54 -70 <0.001
Eastern Dakotas 132 251 -47 0.034 96 +37 0.162
Total 3,387 3,807 -11 0.136 5,220 -35 <0.001
Table 13. Duck breeding population estimates (median, in thousands) for 6 species in the eastern survey area.
Species 2005 2004 % Change from
2004 Average a % Change from
average
Mergansers (common, red-breasted, & hooded) 753 995 -25 b 825 -9
Mallard 412 646 -36 b 546 -25
American black duck 827 1093 -24 b 1002 -18
American green-winged teal 121 226 -46 b 150 -20
Ring-necked duck 883 1257 -30 1032 -14
Goldeneye (common & Barrow’s) 715 748 -5 901 -21
a Average for 1999-2004.
b Significant (P<0.05) determined by non-overlap of Bayesian credibility intervals.
21
the long-term (1966-2004) and 1.9% over the short-term
(1985-2004), in the Atlantic and Mississippi
Flyways combined. Specifically, in the Atlantic
Flyway, the BBS indicated a 4.8% annual increase in
wood ducks over the long-term, and a 2.4% annual
increase over the intermediate-term (1985-2004). In
the Mississippi Flyway, the BBS indicated a 3.3%
annual increase over the long-term, and a 1.7%
annual increase over the intermediate-term. Analysis
of short-term wood duck BBS data over the past 10-
year period (1995-2004) yielded no significant trend
for the Atlantic or Mississippi Flyways, or the two
flyways combined (J. Sauer, U. S. Geological
Survey/Biological Resources Division, unpublished
data).
Weather and habitat conditions during the
summer months can influence waterfowl
production. Good wetland conditions generally
increase renesting effort and brood survival. In
general, 2005 habitat conditions improved over
most of the traditional survey area between May
and July. While no formal July surveys were flown
this year, experienced crew leaders in Montana
and the western Dakotas, the eastern Dakotas,
southern Alberta, and southern Saskatchewan
returned to their May survey areas in early July to
qualitatively assess habitat changes between May
and July. Biologists from other survey areas
communicated with local biologists to get their
impressions of 2005 waterfowl production and
monitored weather conditions. Habitat on most of
the prairies, especially southern Saskatchewan
and eastern Montana improved between May and
July because of abundant summer rain. Even in
Alberta, where a severe drought prevailed in May,
conditions have dramatically improved. For birds
that did not overfly the praries, prospects for
production are good. Habitat conditions in the
northern and eastern areas tend to be more stable
because of the deeper, more permanent water
bodies there. In general, the outlook for production
was rated fair to good in the northern Prairie
Provinces and good to excellent in the eastern
survey area.
Regional Habitat and Population Status
A description of habitat conditions, populations,
and production for each for the major breeding areas
follows. More detailed reports of specific regions are
available in Waterfowl Population Surveys reports,
located on the Division of Migratory Bird
Management’s home page. Some of the habitat
information that follows was taken from these reports
(http://migratorybirds.fws.gov/reports/reports.html).
Southern Alberta: During the fall and winter of
2004/2005 most of prairie southern Alberta (strata
27, 28 and 29) received only 20-60% of normal
precipitation, except in western areas near Rocky
Mountain House, High River and Claresholm,
where much higher-than-normal precipitation
occurred. Spring runoff was below average in
prairie Alberta. Precipitation during April generally
ranged from 25 to 50% of normal in western areas
of Alberta from Grande Prairie south to Pincher
Creek. Southeastern Alberta also had below-normal
April precipitation. Overall, habitat
conditions were poor when the survey was flown.
However, the Aspen Parkland areas of strata
26 and 75 were improved compared to the past
few years. Greater-than-normal precipitation was
recorded in the fall and spring in a band across
the province from Peace River (145% of normal)
to Cold Lake (98% of normal) and south to
Lloydminster (114% of normal). Habitat conditions
ranged from fair in southern stratum 26 to good in
the northern areas of strata 26 and 75. Winter
precipitation in the Grande Prairie area was near
normal. Habitat in the Peace Parklands of
northcentral Alberta improved from generally poor
last year to fair-good.
Overall, May ponds were up 47% relative to
2004, and were similar to the long-term average.
In response, total duck (+27%) and northern
pintail (+75%) numbers were considerably higher
than in 2004, but remained 26% and 61% below
their long-term averages,. Mallards (-39%),
American wigeon (-58%), and scaup (-65%) were
all below their long-term averages, but similar to
last year’s estimates. The northern shoveler
estimate was similar to last year’s, but they are
the only species in this survey area with counts
above (+54%) their long-term average. Blue-winged
teal numbers were 80% higher than in
2004, but similar to their long-term average.
Gadwall, green-winged teal, redhead and
canvasback estimates were all similar to their
2004 counts and long-term averages.
As of July 2005, the western prairies of
Alberta had improved considerably. Eastern
portions of the prairies are still in poor condition.
This area has suffered under a drought for several
years and will require quite a bit of above-normal
precipitation for wetland and upland habitat to
recover. The Aspen Parklands of strata 26 were
very wet due to the above-normal June rains.
Most areas were in good to fair condition in July,
an improvement over May. In strata 75-76,
Palmer drought indices suggested habitat had
22
improved since May. There was little evidence of
renesting, perhaps due to June flooding in some
areas, or because those rains came too late to
stimulate a good renesting effort. Most of the
water received in June absorbed into the dry soil
in strata 27, 28, and 29. However, in stratum 26
wetlands were recharged and duckling production
appeared improved relative to last year and 2003.
Southern Saskatchewan: The grasslands of
strata 32 and 33 received average to below-average
precipitation during the winter. Spring
precipitation was patchy across the grasslands
during April and May and much of the area
continued to receive only average precipitation;
the exceptions were in the southwest and
northwest, which received above average rainfall.
Upland habitat throughout the grasslands
appeared to be in better shape than in 2004. As
of May, predicted production from the grasslands
ranged from poor in the western and southern
grasslands to fair in the southwest and central
survey areas, and good along the Missouri Coteau
into the Alan Hills and west to the Alberta border.
The extreme northwestern grasslands had
excellent water and habitat conditions, and ducks
were present in high numbers. The northwestern
parklands (stratum 30) received above-average
precipitation during the winter and spring and both
upland nesting cover and wetlands were in good
to excellent condition. The northeastern parklands
received below-average to average precipitation
during the winter and average to above-average
precipitation during the spring. Most of the upland
and wetland habitat within the stratum was in
good to excellent condition for duck nesting and
brood rearing.
The May pond estimate was 65% higher than
last year's count, and was 24% above the long-term
average. Total ducks were 38% above their
2004 counts, and 9% higher than their long-term
average. Except for mallards, gadwall and
canvasbacks, which were unchanged from their
2004 estimates, all other species in the region
were higher than their 2004 estimates. American
wigeon (+130%), green-winged teal (+189%),
blue-winged teal (+38%), northern shovelers
(+68%), northern pintails (+81%) and redheads
(+72%) were all vastly improved relative to their
2004 estimates. However, northern pintails,
American wigeon, and mallards remained 30%,
31%, and 17% below their long-term averages,
respectively. Redheads were similar to their long-term
average. Green-winged teal (+58%), gadwall
+31%), blue-winged teal (+32%), and northern
shoveler (+107%) numbers were well above long-term
averages. Scaup were 106% above their
2004 estimate, but similar to their long-term
average. Canvasbacks were similar to their 2004
estimate and long-term average.
The northeast parklands region (stratum 31)
remained in excellent condition during the weeks
following the May survey. Upland habitat was in
good condition and most of this area had good-excellent
wetland conditions, with some flooded
crops. The northwest portion of the parklands
also had good-excellent habitat in July.
Sheetwater was evident in many portions of
stratum 32, north and east of Kindersley, and
southeast of Regina. Stratum 33 was rated fair-good,
and conditions had improved since May.
Stratum 30 was drier than in May, but still had
good brood water and excellent cover.
Southeastern Saskatchewan (Strata 34 and 35)
also received much water and had excellent
wetland conditions. However, many wetlands
were void of ducks, and production may have
been hampered due to flooding. Overall, the
survey area was rated good-excellent for re-nesting
potential and duckling production.
Southern Manitoba: Habitat conditions for
breeding waterfowl have improved over last year
in southern Manitoba (strata 24, 36-40). Above-average
precipitation in the fall and winter and
rapid snowmelt in March resulted in heavy runoff
into wetland basins this spring. The southwestern
part of this survey region (strata 39 and 40) was in
excellent condition, and as of May, along with
southeastern Saskatchewan, was the only large
portion of the Prairies so classified. The rest of
the survey area (stratum 25) also had improved
water conditions, but more wet weather was
needed to improve residual cover, which is still
sparse. As of May, good production was expected
from this area, provided weather conditions
remained favorable for the rest of the spring and
summer.
The May pond count was 40% higher than the
2004 estimate, but similar to the long-term average.
Total ducks, blue-winged teal, redheads, and
canvasbacks were similar to their 2004 estimates
and long-term averages. Mallards were similar to
their 2004 estimate, but 21% above their long-term
average. Northern pintail (+71%) and scaup (+91%)
estimates were higher than to those of 2004, but
remained 40% and 56% below their long-term
averages, respectively. The gadwall estimate was
unchanged relative to last year, and was 84% above
the long-term average. The American wigeon
23
estimate improved dramatically (+893%) relative to
last year’s record low, but remained 45% below the
long term average for the survey area. Green-winged
teal numbers were also higher than last
year (+103%) but similar to their long-term
average. Northern shoveler numbers were similar
to last year’s, but were 100% above their long-term
average.
Manitoba received much higher than normal
precipitation from May to July, which made for
excellent brood-rearing habitat, but flooding may
have destroyed waterfowl nests in many areas.
As of July, the southwestern corner of Manitoba
remained in excellent condition. A band of habitat
running from Minnedosa south through Brandon
was rated good for production. Conditions
worsened to the east, with stratum 25, and the
areas just to the west of Lake Manitoba and Lake
Winnipegosis rated only fair. The center of the
province along the North Dakota border was also
rated good. In strata 37 and 38, east of Lake
Manitoba, conditions were poor for duck
production. Overall however, good to excellent
production was expected in southern Manitoba.
Montana and Western Dakotas: In May,
conditions in the Western Dakotas and Montana
(Strata 41-44) were much drier this year than they
were the same time last year, due to lack of
precipitation in the fall and winter coupled with
warm winter temperatures. Overall, conditions for
breeding waterfowl were rated fair to poor.
The region roughly north of the Missouri River in
eastern Montana (stratum 41) experienced a mild
winter following a relatively dry fall in 2004. By
early May precipitation was less than 50% of
normal with less than average amounts of run off
along the western portion of the region. The
border between U.S. and Saskatchewan/Alberta,
an important northern pintail area, was only fair.
Conditions were poor in the region between Havre
and Great Falls, but improved between Glasgow
and Plentywood. During the latter part of the 2005
survey period Montana received more precipitation
and short-term indices were actually well above
normal. Upland vegetation responded well to the
added moisture, and this turned a predicted dismal
year into a near-normal year for waterfowl
production in northern Montana.
The portion of eastern Montana roughly south
of the Missouri River (Stratum 42) had a mild
winter with below-average precipitation that was a
continuation of a 3-year drought affecting most of
eastern Montana. However, on May 8 a
significant storm system produced heavy rain and
snow throughout much of stratum 42. The long-term
lack of moisture in the area meant this water
only slightly improved conditions for waterfowl.
Some semi-permanent wetlands benefited from
the precipitation and most of stratum 42 was
classed as fair, with a small area of good habitat
southeast of Miles City.
In the western Dakotas (strata 43-44), waterfowl
production potential was largely rated fair, and
poor along the border between North and South
Dakota. As of May, production in these regions
was expected to be below average.
In Montana and the western Dakotas, May
pond counts were similar to the 2004 estimate,
and 27% higher than the long-term average. Total
ducks were 20% lower than both their 2004
estimate and their long-term average. Northern
pintails and canvasbacks were 43% and 60%
below last year’s estimates, and were 73% and
39% below their long-term averages for the survey
area. Mallards, American wigeon, and scaup were
all similar to their 2004 estimates, and remained
23%, 39%, and 70% below their long-term
averages, respectively. Green-winged teal were
similar to last year’s estimate, and were 113%
above their long-term average for the survey area.
Gadwall, northern shoveler, and blue-winged teal
estimates were similar to those of 2004, and to
long-term averages. The estimate for redheads
did not differ from last year’s, but this species
remained 70% below its long-term average for the
region.
Habitat conditions in the area improved
markedly following May surveys. Near-record
rainfall filled wetlands and brought about growth of
green vegetation. The high-line region near the
Canadian border even improved to “good” as of
July. However, this rain likely helped only the
latest nesters and their broods. Much favorable
habitat was unoccupied, as many ducks likely
moved elsewhere before the rains came. Average
numbers of broods were observed. However,
good wetland conditions should produce good
brood survival, and overall production in the
region should nonetheless approach average,
though cold, wet weather in June may have
hampered duckling survival somewhat. Overall,
production potential for the survey area was
considered average as of July.
Eastern Dakotas: Fall of 2004 in eastern South
and North Dakota (Strata 45-49) was milder than
average, with some rain in October. Wetland
freeze-up did not occur in North Dakota until
nearly the end of November, almost a month later
than normal. By the start of the May survey, most
of eastern South Dakota had received no more
24
than 2 inches of precipitation since 1 November,
and the entire state of North Dakota was 20% -
60% below its normal annual precipitation. As a
result of the dry and mild winter, much of the
eastern South Dakota waterfowl breeding habitat
was considered poor. Temporary and seasonal
wetland basins were dry on much of the drift plain,
and most had been cultivated. Many dugouts and
small streams were dry as well. In the southern
portions of the survey area (stratum 49) and the
prairie coteau (eastern stratum 48 and western
stratum 49), water conditions were slightly better,
and these regions were considered fair waterfowl
nesting habitat. Some overflight likely occurred as
the generally poor conditions offered little
attraction for breeding birds to settle and establish
territories. Upland nesting cover in South Dakota
was poor on the drift prairie due to dry conditions
and tillage through wetland basins. Nesting cover
in the coteau was adequate.
Eastern North Dakota was generally in better
condition than eastern South Dakota. Most of the
eastern third of the North Dakota survey unit was
considered fair or good habitat for nesting
waterfowl. Late May rains created temporary and
seasonal water and improved the condition of
existing wetlands. Isolated areas of good habitat
were observed around Devils Lake and in the
extreme northern portion of the Missouri Coteau.
The northern half of the coteau was considered
fair and most of the remainder of North Dakota
was poor. In North Dakota, wetland basins in the
drier areas of the drift plain offered slightly better
nesting cover than the drift areas of South Dakota.
In all other regions of North Dakota, nesting cover
was typical for each physiographic region.
May pond numbers were similar to last year's
figure, and 20% below the long-term average. The
total duck estimate was 14% lower than the 2004
count, but remained 10% above the long-term
average. Mallard numbers were similar to those of
2004, and remained, 60% above their long-term
average. Redheads and northern pintails were
similar to their 2004 estimates, but were 34% and
45% below their long-term averages, respectively.
Gadwall, and scaup estimates were 31% and 47%
below those of 2004, but were 46% and 37%
above their long-term averages, respectively.
Green-winged teal counts were down 47% relative
to 2004, but were similar to the long-term mean
for this survey area. Northern shoveler,
canvasback, blue winged teal, and American
wigeon estimates were similar to last year’s
estimates and their long-term averages.
The eastern Dakotas received significant
precipitation between May and July. In South
Dakota, however, significant wetland
improvements were restricted to the extreme
northeastern portion of the state, with some slight
improvement west of Sand Lake National Wildlife
Refuge. The overall prediction for production from
eastern South Dakota remained below average.
In eastern North Dakota, by contrast, wetland
conditions were improved over the entire survey
area. Some flooding of nests may have occurred,
but upland and emergent vegetation was good to
excellent in many areas. Conditions in North
Dakota should favor good brood survival. Overall,
average waterfowl production was expected in the
eastern Dakotas as of July 2005.
Northern Saskatchewan, Northern Manitoba, and
Western Ontario: In northern Saskatchewan and
Manitoba (strata 21-25), winter snowfall was
plentiful throughout most of the region. Spring,
and the accompanying ice breakup occurred
relatively early across the region. As a result,
many rivers, lakes and streams were high in May,
which flooded vast areas of prime nesting habitat.
Although breakup came early, late spring was cold
and wet, which could adversely affect production.
Many small beaver-pond wetlands were ideal for
duck nesting; however, due to the widespread
flooding, a large portion of the survey area was
rated fair as of May, and the smaller remaining
portion was rated good. Western Ontario (stratum
50) was also rated as good.
The total-duck estimate was 21% below the
2004 estimate, and 10% below the long-term
average. The scaup estimate was 40% lower than
last year’s, and 41% lower than the long-term
average. All other species were similar to their
2004 estimates. The green-winged teal estimate
was 59% higher than the long term average for
the region. American wigeon (-31%), northern
shovelers (-34%), blue-winged teal (-48%),
redheads (-53%), and northern pintails (-80%)
were all below their long-term averages for the
survey area. Mallards, gadwall, and canvasbacks
were all similar to their long-term averages.
As of July, conditions were rated mostly fair,
with some areas of good, throughout most of
northern Saskatchewan and Northern Manitoba.
Northern Alberta, Northeastern British Columbia, and
Northwest Territories: In northern Alberta,
northeastern British Columbia, and the Northwest
Territories (strata 13-18, 20, 75-77), conditions were
fair in the center of the survey area. Northwest of
Cree Lake was rated good, as was the northeastern
25
portion of the survey area near Gillam. The
southwestern corner of the survey region near
Nipawin was also rated good. Heavy flooding in
many regions, especially those rated fair, likely
hampered nesting. Most of the survey area in
northern Alberta and northeastern British
Columbia (stratum 77) was fairly dry because of
below-normal spring precipitation. Spring came
early, with above-average temperatures in April,
but a cold-snap in May delayed phenology
somewhat. Water levels were low in most
wetlands. Only permanent lakes and large beaver
flowages had normal habitat available for
waterfowl. Overall, stratum 77 was rated as fair.
The Athabasca Delta (stratum 20) experienced
below normal spring flooding, and was rated fair.
All of the lakes surveyed had lower than normal
water levels. Many of smaller associated wetlands
were dry or almost dry and the normally deeper
sloughs had reduced water levels. Spring was
earlier than normal in the Delta, with no ice on
Lake Claire.
Spring arrived earlier than normal in the
southern Northwest Territories (stratum 17), and
the entire stratum was rated good. All wetlands
were ice free, including the mid-size and larger
lakes at higher elevation on the Horn Plateau.
Southern portions of the stratum had water
overflowing from beaver flowages and small size
ponds from recent rains. The Canadian Shield
(strata 16 and 18) was rated as fair because of
later than normal spring and the subsequent late
ice breakup. Water levels were near or above
normal in this portion of the survey area.
The Middle Mackenzie Valley (stratum 15) was
rated as good due to average winter snow-melt.
All mid-size and large lakes were open by June
10. The Upper Mackenzie Valley Boreal
Plains/Tundra (stratum 14) experienced a slightly
earlier normal spring, which provided good
breeding habitat for the early nesting waterfowl
species. This stratum was rated as good.
Waterfowl breeding habitat was in better shape on
the MacKenzie River Delta (stratum 13) than last
year, although production of early-nesting species
was likely tempered somewhat by the late spring
in the eastern Northwest Territories portion of the
survey area. Due to early ice breakup and normal
water conditions, this area was rated good.
Total-duck numbers were 20% below the 2004
estimate, and 35% below the long-term average
for the survey area. Mallards (-31% from 2004, -
51% from long-term average), green-winged teal
(-48% from 2004, -42% from long-term average),
and Northern pintails (-44% from 2004, -72% from
long-term average) were all below their 2004
estimates and long-term averages. American
wigeon and scaup numbers were similar to 2004
counts, but remained 36% and 49% below their
long-term averages, respectively. Gadwall
numbers were 44% below their 2004 estimate, but
remained 66% above their long-term average.
Blue-winged teal, northern shovelers, redheads,
and canvasbacks were all similar to last year’s
estimates and long-term averages.
The northernmost regions of northern Alberta and
northeastern British Columbia remained very dry
following May surveys. Further south, production
potential as of July was rated good-very good.
Alaska, Yukon Territory, and Old Crow Flats: In
Alaska, the Yukon Territory, and Old Crow Flats
(strata 1-12), breeding conditions depend largely
on the timing of spring phenology, because
wetland conditions are less variable than on the
prairies. Except for the North Slope, Alaska
experienced an early spring, a weather pattern
that generally favors waterfowl production.
Interior Alaska was up to two weeks early, while
on the western tundra phenology was
approximately one week earlier than normal.
Warm temperatures and heavy snowfall resulted
in some flooding along many rivers, especially the
Koyukuk, Innoko, and the lower Yukon. Overall,
excellent to good production was anticipated
following the May survey, except for flooded
areas, and for the Arctic Coastal Plain, where only
fair to poor production was expected.
Estimates of all duck species were similar to
those of 2004, with the exception of redheads,
which were 91% below their 2004 count, and 84%
below their long-term average. Total duck (+45%),
mallard (+101%), American wigeon (+73%),
green-winged teal (+103%) and northern shoveler
(+158%) estimates were all above their long-term
averages. Gadwall, blue-winged teal, northern
pintail, canvasback, and scaup populations all
remained similar to their long-term averages.
Warm temperatures and adequate, but not
excessive, moisture across much of Alaska during
June and July maintained the mostly excellent
conditions observed by biologists in May. Overall,
little changed, and excellent production was
anticipated for most of Alaska, with fair to poor
conditions prevailing on the Artic Coastal Plain.
Eastern Survey Area: Breeding habitat conditions
were good throughout most of the eastern U.S.
and Canada (strata 51-72). Northern portions of
Labrador and Quebec and all of Newfoundland were
rated excellent. The western James Bay lowlands
was also excellent for breeding waterfowl because of
26
early spring phenology. Along the coast of Maine
and the Maritimes, conditions were only fair for
breeding waterfowl due to flooding. Habitat
conditions in Maine (stratum 62) were excellent.
Above-average snowfall over the winter and
heavy rains in April made for full or flooded ponds
and wetlands throughout the state. Significant ice
was only observed on larger lakes north of
Houlton. Temperatures in Maine were average
during early spring, timing of ice breakup was
normal and any flooding likely had minimal effects
on nesting waterfowl. Habitat conditions in New
Brunswick (stratum 63) were fair to good.
Snowfall was average, however heavy rains in
April contributed to major flooding along the St.
John River and its tributaries. Wetlands, ponds
and lakes were full or flooded throughout the
province. Temperatures were below average
during early spring, but break up was complete.
Flooding reduced available habitat and may have
disrupted nesting. Habitat was in excellent
condition on Prince Edward Island (stratum 65).
Despite heavy precipitation in April, no flooding
was observed. All wetlands and ponds were full,
and there was sheet water on many of the
agricultural fields. Temperatures were below
average during early spring, but water and habitat
were plentiful, and nesting chronology appeared
normal. Conditions in Newfoundland (statum 66)
and Labrador (stratum 67) were excellent.
Winter precipitation and temperatures were
near long-term averages across much of southern
Ontario and Quebec. Spring weather was
relatively mild, and precipitation was below
normal, in southern Ontario, and habitats were in
poor condition in the extreme southwest ranging
to fair condition to the west of Toronto. Spring
rains near the Bruce Peninsula and south of the
Georgian Bay improved habitat conditions there,
recharging many seasonal wetlands. In the
hardwood-boreal transition region east of
Georgian Bay and into the agricultural regions of
the Ottawa River Valley around Ottawa wetland
conditions were also generally good. Somewhat
drier conditions were noted in the St. Lawrence
lowlands of New York and little temporary or
seasonal water was observed. Winter
temperatures in Quebec were normal, or slightly
below normal. Precipitation was below normal,
except for portions of the northeast near Kuujjuaq.
Agricultural regions of extreme southeastern
Quebec were relatively dry with little standing
water observed in agricultural drainage ditches.
Wetlands were in good condition in the St.
Lawrence lowlands north through Quebec City.
Overall, habitat conditions were considered good
in southern Quebec, as wetland levels were
adequate, though slightly below normal.
Spring melt was uncharacteristically early in
northeastern Ontario in the James Bay and
Hudson Bay lowlands. At the time of the survey in
late May, no ice was observed on any wetlands or
lakes until within 30 km of the Hudson Bay
shoreline and then only the largest lakes retained
residual ice cover. Good conditions for nesting
waterfowl were the norm throughout Ontario.
Mergansers (-25%), mallards (-36%), American
black ducks (-24%), and green-winged teal (-46%)
were all below their 2004 estimates (Table 13).
Ring-necked ducks and goldeneyes were similar
to their 2004 estimates. None of these species
differed from their long-term averages for the
survey area.
As of July, habitat conditions in the Maritimes
were excellent following additional precipitation in
June. However, waterfowl production may have
been hampered by cold wet weather. Good-very
good production was expected in Quebec, where
habitat remained good. Despite continued
drought, good production was expected in
Ontario, and above-average June temperatures
brought increased plant growth. Observers
reported evidence of good brood numbers in July.
Other areas: Conditions remained dry in many areas
along the West Coast of the U.S. and Canada. In
Washington, total mallards in the breeding
population were estimated at 40,800, a small
increase (2%) from last year’s count, but they
remained 24% below the long-term average. The
estimate for total ducks (111,500) was down 13%
from 2004 and 29% from the long-term average.
American wigeon, green-winged teal, northern
shovelers and redheads were the species whose
numbers fell the most. Total duck numbers were
up 5% in the wetland habitats associated the
irrigation projects of the Yakima Valley and the
Columbia Basin where water levels remained
more stable, but the dryland habitats that depend
on snowmelt to recharge potholes saw total duck
reductions of 11% from 2004 and 45% from the
long term average. Pothole numbers were down
41% from 2004 and 61% relative to the long-term
average, the driest year since 1992.
In British Columbia, the winter of 2004-05 was
characterized by a good snowpack early in winter,
followed by rain and warm weather during the
later part of winter. Water levels of low-elevation
wetlands were higher than in 2004 but overall
lower than average. Breeding habitat conditions
were better than in May 2004, but remained poor
overall. The total number of ducks observed in
27
2005 was 24% lower than in 2004 (also a drought
year), and 17% below the (1988-2004) long-term
average. Total diving ducks were 22% lower than
in 2004 and 8% below the long-term average.
Total dabbling ducks were 24% lower than in 2004
and 35% lower than the long-term average. The
total number of duck breeding pairs was 11%
lower than in 2004 and 22% lower than the long-term
average. For diving ducks, the number of
breeding pairs was 8% lower than in 2004 and 4%
lower than the long-term average. The total
number of dabbling duck pairs was 15% lower
than in 2004 and 38% lower than the long-term
average. In California, the total-duck estimate was
615,000, 49% higher than last year’s estimate of
412,800, but similar to the long-term average.
Mallards (318,000) were not significantly different
from their 2003 estimate (262,000) or their long-term
average of 372,000. In Oregon, similar trends existed
for estimates of total ducks and mallards. Both were
similar to 2004 estimates, but were 25% and 26%
below their long-term averages, respectively.
Conditions were variable in the interior-western
U.S. In Nebraska, waterfowl numbers rebounded
dramatically from 2004’s low numbers. Total duck
numbers were up 168% to 117,100. At 81,100, the
mallard count was 350% higher than the long-term
average. In Nevada total duck and mallard numbers
were down relative to last year. Total ducks
numbered 10,700, compared to 12,000 in 2004. Only
700 mallards were counted, compared to 1,700 last
year. Wyoming no longer conducts a May
breeding waterfowl survey, but biologists there
reported that the eastern portion of the state
remains in a hydrologic drought, and many
wetlands remain dry. However, there was enough
precipitation this spring to improve upland nesting
habitat. Overall, waterfowl production in eastern
Wyoming should be poor. Most of western
Wyoming has much improved wetland conditions
compared to the last few years, and waterfowl
production should be good.
Habitat conditions around the Great Lakes were
variable. Minnesota experienced an early spring ice
breakup, and an improvement in wetland conditions.
Minnesota pond numbers increased 22% relative to
2004, and were similar to the 1968-2004 average.
Mallard numbers (238,500) were down 36% relative
to the 2004 estimate of 375,000 but still higher than
the long-term average of 223,000. In Wisconsin,
spring came early and was warm and dry, and
wetland quality and quantity was poor. Brood habitat
remained poor through June, with little rainfall in
important waterfowl breeding areas. Wisconsin total
duck numbers were similar to the 2004 estimate and
73% above the 1974-2004 average. Mallard
numbers were 38% higher than their 2004 level, and
81% above the long-term mean. In Michigan, wetland
counts were near their 1992-2004 average, and the
total duck estimate was 20% higher than last year’s.
Mallard numbers in Michigan (238,500) were 30%
below their 2004 count, and remained 46% below the
long-term average. In the Atlantic Flyway states
along the East Coast of the U.S., habitat conditions
were good for nesting waterfowl. Overall, normal
late winter and early spring rains provided good
nesting habitat. However, some areas, especially
near the coast, experienced heavy rains and
flooding near peak hatch, likely resulting in loss of
nests and broods. Canada goose nests and
broods were likely most affected by the timing of
these rains and floods. Temperatures were about
10 degrees below normal across the surveyed
area. In some areas, this likely caused a delay in
nesting or renesting phenology. Some areas
experienced drying conditions and were nearly dry
by the end of May, despite good rains earlier.
Total duck and mallard numbers from the Atlantic
Flyway’s Breeding Waterfowl survey were similar to
the 2004 estimates, and to their long-term averages.
Mallard Fall-flight Index
The mid-continent mallard population is composed
of mallards from the traditional survey area, and from
Michigan, Minnesota, and Wisconsin. The 2005
estimate is 7.5 ± 0.3 million which is 10% lower than
the 2004 estimate of 8.3 ± 0.3 million. The projected
mallard fall flight index (Fig. 3), was 9.3 ± 0.1
million, similar to the 2004 estimate of 9.4 ± 0.1
million birds. These indices were based on revised
mid-continent mallard population models, and
therefore differ from those previously published
(USFWS Adaptive Harvest Management Report
2005, Runge et al. 2002)
0
2
4
6
8
10
12
14
16
18
1970 1975 1980 1985 1990 1995 2000 2005
Year
Millions
Fig. 3. Estimates and 95% confidence intervals for the
size of the mallard population in the fall.
28
REFERENCES
Drought Watch on the Prairies, 2005. Agriculture
and Agri-Food Canada.
(www.agr.ca/pfra/drought.htm).
Environment Canada, 2005. Climate Trends and
Variations Bulletin. Green Lane Internet
Publication,Downsview,ON.
(http://www.msc-smc.
ec.gc.ca/ccrm/bulletin/national_e.cfm)
Link, W. A., and J. R. Sauer. 2002. A hierarchical
model of population change with application to
Cerulean Warblers. Ecology 83:2832-2840.
NOAA/USDA Joint Agriculture Weather Facility.
2005. Weekly Weather and Crop Bulletin.
Washington, DC.(www.usda.gov/oce/waob/jawf).
Royle, J. A., W. A. Link, and J.R. Sauer. 2002.
Statistical mapping of count survey data.
Pages 625-638 in Predicting Species
Occurances: Issues of Scale, and Accuracy
(Scott, J. M., P. J. Heglund, M. L. Morrison, J.
B. Haufler, M. G. Raphael, W. A. Wall, and F.
B. Samson, editors). Island Press. Covello,
CA, USA.
Runge, M. C., F. A. Johnson, J. A. Dubovsky, W.
L. Kendall, J. Lawrence, J. Gammonley.
2002. A revised protocol for the Adaptive
Harvest Management of Mid-Continent
Mallards. (migratorybirds.fws.gov/reports/
ahm02/MCMrevise2002.pdf)
Sauer, J.R., and S. Droege. 1990. Wood duck
population trends from the North American
Breeding Bird Survey. Pages 159-165 in L.H.
Frederickson, G. V. Burger, S.P. Havera, D.A.
Graber, R.E. Kirby, and T.S. Taylor, eds.
Proceedings of the 1988 North American Wood
Duck Symposium, St. Louis, MO.
U.S. Fish and Wildlife Service. 2005. Adaptive
Harvest Management: 2005 Duck Hunting
Season. U.S. Dept. Interior, Washington, D.C.
U.S. Fish and Wildlife Service. 2005.
Waterfowl Population Survey Section area
reports.
Wilkins, K. A., and M. C. Otto. 2005. Trends in
duck breeding populations, 1955-2005. U.S.
Dept. Interior, Washington, D.C. 21pp.
29
STATUS OF GEESE AND SWANS
Abstract: We provide information on the population status and productivity of North American Canada geese
(Branta canadensis), brant (B. bernicla), snow geese (Chen caerulescens), Ross’ geese (C. rossii), emperor
geese (C. canagica), white-fronted geese (Anser albifrons), and tundra swans (Cygnus columbianus). The
timing of spring snowmelt in important goose and swan nesting areas in most of the Arctic and subarctic was
near average, or earlier than average in 2005. Delayed nesting phenology or reduced nesting effort was
indicated for only Alaska’s North Slope and areas of the eastern Canadian High Arctic. Primary abundance
indices in 2005 increased from 2004 levels for 12 goose populations and decreased for 13 goose populations.
Primary indices in 2005 increased for western tundra swans and decreased for eastern tundra swans. Of these
27 populations, the Atlantic, Eastern Prairie, Mississippi Flyway Giant, and Aleutian Canada goose populations,
and the Western Arctic/Wrangel Island snow goose population displayed significant positive trends during the
most recent 10-year period (P < 0.05). Only Short Grass Prairie Population Canada geese and Pacific brant
displayed significant negative 10-year trends. The forecast for the production of geese and swans in North
America in 2005 is generally favorable and improved from that of 2004.
This section summarizes information regarding the
status, annual production of young, and expected fall
flights of goose and tundra swan populations in North
America. Information was compiled from a broad
geographic area and is provided to assist managers
in regulating harvest.
Most populations of geese and swans in North
America nest in the Arctic or subarctic regions of
Alaska and Canada (Fig. 1), but several Canada
goose populations nest in temperate regions of the
United States and southern Canada (“temperate-nesting”
populations). The annual production of
young by northern-nesting geese is influenced
greatly by weather conditions on the breeding
grounds, especially the timing of spring snowmelt
and its impact on the initiation of nesting activity (i.e.,
phenology). Persistent snow cover reduces nest site
availability, delays nesting activity, and often results
in depressed reproductive effort and productivity. In
general, goose productivity will be better than
average if nesting begins by late May in western and
central portions of the Arctic, and by early June in the
eastern Arctic. Production usually is poor if nest
initiations are delayed much beyond 15 June. For
temperate-nesting Canada goose populations,
recruitment rates are less variable, but productivity is
influenced by localized drought and flood events.
METHODS
We have used the most widely accepted
nomenclature for various waterfowl populations, but
they may differ from other published information.
Species nomenclature follows the List of Migratory
Birds in Title 50 of the Code of Federal
Regulations, Section 10.13. Some of the goose
populations described herein are comprised of more
than 1 subspecies and some light goose populations
contain lesser snow geese and Ross’ geese.
Population estimates for geese are derived from a
variety of surveys conducted by biologists from
federal, state, and provincial agencies, and
universities (Appendices B, I, and J). Surveys
include the Midwinter Survey (MWS, conducted each
January in wintering areas), the Waterfowl Breeding
Population and Habitat Survey (WBPHS, see Duck
section of this report), surveys specifically designed
for various populations, and others. When survey
methodology allowed, 95% confidence intervals were
presented with population estimates. The 10-year
trends of population estimates were calculated
through regression of the natural logarithm of survey
results on year, and slope coefficients were
presented and tested for equality to zero (t-test).
Changes in population indices between the current
and previous years were calculated, and, where
possible, assessed with a z-test using the sum of
sampling variances for the 2 estimates. Primary
abundance indices, those related to population
objectives, are described first in population-specific
sections and graphed when data are available.
Because this report was completed prior to the final
annual assessment of goose and swan reproduction
the annual productivity of most populations can only
be predicted qualitatively. Information on habitat
conditions and forecasts of productivity were based
primarily on information from various waterfowl
surveys and interviews with field biologists. These
reports provide reliable information for specific
locations but may not provide accurate assessment
for the vast geographic range of waterfowl
populations.
30
Fig. 1. Important goose nesting areas in Arctic and subarctic North America.
La Perouse Bay
Cape Henrietta
Maria
Banks
Island
Bylot
Island
Southampton
Island
Ungava
Peninsula
James
Bay
Akimiski
Island
McConnell
River
Queen
Maud
Gulf
Copper
River
Yukon River
Kuskokwim River
Yukon-Kuskokwim
(Y-K) Delta
Baffin Island
Foxe
Basin
Labrador
Plain of
Koukdjuak
Wrangel
Island
Anderson
River
Mackenzie
River Delta
Victoria I
C. Churchill
North Slope
Hudson Bay
Parry
Islands
Greenland
31
RESULTS AND DISCUSSION
Conditions in the Arctic and Subarctic
The timing of spring snowmelt in most important
northern goose and swan nesting areas was near
average, or earlier than average in 2005. Delayed
nesting phenology or substantially reduced
productivity was indicated for only Alaska’s North
Slope and areas of the eastern Canadian High Arctic.
Conditions were exceptionally favorable on Wrangel
Island, Russia and, in stark contrast to 2004, on
areas around southern Hudson Bay and northern
Quebec. The snow and ice cover graphic (Fig. 2,
National Oceanic and Atmospheric Administration)
illustrates the generally reduced snow cover across
subarctic Canada in 2005 compared with 2004.
Fig. 2. The extent of snow and ice cover in North America on 2
June 2005 and 2 June 2004 (data from National Oceanic and
Atmospheric Administration).
Conditions in Southern Canada and the United
States
Conditions that influence the productivity of
Canada geese vary less from year to year in these
temperate regions than in the Arctic and subarctic.
Given adequate wetland numbers and the
absence of flood events, temperate-nesting
Canada geese are reliably productive. Wetland
abundance in much of this area increased in
2005, including several areas of the west that had
been gripped by drought for several years.
However, in some areas (e.g., OR, UT, ND, and
OH) spring rains or snows may have reduced
productivity by flooding nests or decreasing the
survival of goslings. Most temperate-nesting
Canada goose populations likely experienced
average or above average nesting conditions in
2005.
Status of Canada Geese
North Atlantic Population (NAP): NAP Canada
geese principally nest in Newfoundland and
Labrador. They generally commingle during winter
with other Atlantic Flyway Canada geese, although
NAP geese have a more coastal distribution than
other populations (Fig. 3).
During the 2005 WBPHS, biologists estimated
51,300 (+ 23,100) indicated pairs (singles plus
pairs) within NAP range (strata 66 and 67), 24%
fewer than in 2004 (P = 0.436, Fig. 4). Indicated
pair estimates have declined an average of 4%
per year since surveys were initiated in 1996 (P =
0.131). The 2005 estimate of 129,900 (+ 62,800)
total Canada geese was 34% lower than last
year’s estimate (P = 0.315). Total goose
estimates have declined an average of 3% per
year during 1996-2005 (P = 0.177). The pair
density determined by the 2005 expanded CWS
helicopter plot survey was the lowest since 1995,
but clutch sizes were above average. Spring
phenology was early and nesting conditions were
favorable for geese in Newfoundland and
Labrador in 2005. A fall flight similar to that of
2004 is expected.
Year
'96 '97 '98 '99 '00 '01 '02 '03 '04 '05
Thousands
0
20
40
60
80
100
120
140
160
Fig. 4. Estimated number (and 95% confidence intervals) of North
Atlantic Population Canada geese breeding pairs during spring.
Atlantic Population (AP): AP Canada geese nest
throughout much of Quebec, especially along
Ungava Bay, the eastern shore of Hudson Bay, and
32
Tall Grass
Prairie
North
Atlantic
Southern
James Bay
Lesser and
Atlantic Taverner’s
Mississippi
Valley
Short Grass
Prairie
Pacific
Dusky
Cackling
Hi-line
Western Prairie
Eastern
Prairie
Atlantic
Flyway
Resident
Aleutian
Rocky
Mountain
Great
Plains
Mississippi
Flyway
Giant
Fig. 3. Approximate ranges of Canada goose populations in North America.
33
on the Ungava Peninsula. The AP winters from New
England to South Carolina, but the largest
concentrations occur on the Delmarva Peninsula
(Fig. 3).
Spring surveys in 2005 yielded an estimate of
162,400 (+ 24,700) indicated breeding pairs, 7%
fewer than in 2004 (P = 0.527, Fig. 5). However,
survey timing in relation to hatch was slightly late this
year which may have reduced detection of goose
pairs. Breeding pair estimates have increased an
average of 17% per year during 1996-2005 (P <
0.001). The estimated total spring population of
1,140,800 (+ 177,600) geese in 2005 was 12%
higher than that of last year (P = 0.312). These
estimates were likely inflated by the presence of
many molt migrants in 2005 and 2004. Mild spring
temperatures and rapid snowmelt led to earlier than
average nesting phenology in much of the AP range.
The proportion of indicated pairs observed as singles
(61%) was the highest recorded since 1993,
suggesting an excellent nesting effort this year. The
average clutch size and the number of nests found
on Hudson Bay survey plots were the highest
recorded since 1997. Nest success also appeared
high. On Ungava Bay study areas in 2005, clutch
sizes were 11% above average, nest densities were
near average, nest predation rates were similar to
2004, and productivity was expected to be good. A
fall flight larger than that of last year is expected.
Year
'88 '89 '90 '91 '92 '93 '94 '95 '96 '97 '98 '99 '00 '01 '02 '03 '04 '05
Thousands
0
25
50
75
100
125
150
175
200
Fig. 5. Estimated number (and 95% confidence intervals) of
Atlantic Population Canada goose breeding pairs in northern
Quebec.
Atlantic Flyway Resident Population (AFRP): This
population of large Canada geese inhabits southern
Quebec, the southern Maritime provinces, and all
states of the Atlantic Flyway (Fig. 3).
Surveys during spring 2005 estimated 1,064,700 (+
189,000) AFRP Canada geese in this population
(Fig. 6), about 9% more than in 2004 (P = 0.523).
These estimates have increased an average of 1%
per year over the last 10 years (P = 0.088). The
spring of 2005 was wetter and cooler than average
across AFRP states. Although some flooding
occurred in northeast states, observations during
banding programs indicated gosling production was
at least as high as in 2004. The 2005 fall flight is
expected to be similar to that of 2004.
Year
'89 '90 '91 '92 '93 '94 '95 '96 '97 '98 '99 '00 '01 '02 '03 '04 '05
Thousands
0
200
400
600
800
1000
1200
1400
1600
Fig. 6. Estimated number (and 95% confidence intervals) of
Atlantic Flyway Resident Population Canada geese during spring.
Southern James Bay Population (SJBP): This
population nests on Akimiski Island and in the
Hudson Bay Lowlands to the west and south of
James Bay. The SJBP winters from southern
Ontario and Michigan to Mississippi, Alabama,
Georgia, and South Carolina (Fig. 3).
Breeding ground surveys indicated a spring
population of 46,300 (+ 12,600) Canada geese in
2005, 54% lower than last year (P < 0.001, Fig. 7).
These estimates have decreased an average of 6%
per year since 1996 (P = 0.051). The estimate of
breeding pairs in 2005 declined to 21,100 (+ 6,200),
44% lower than in 2004 (P = 0.014), and a record low
on Akimiski Island. However, SJBP biologists
believe the survey results underestimated the
population in 2005 because: 1) the late timing of
surveys in relation to hatch reduced detection of
nesting geese, 2) fewer than average non-breeding
SJBP geese may have remained on the study area
this late, and 3) use of a different survey plane which
in limited comparison flights yielded lower estimates
than the plane used previously. Survey biologists
indicated that temperate-nesting molt migrants likely
were not a factor in 2005 or 2004 surveys. Lower
than average snowfall and above average late-winter
temperatures contributed to a spring thaw in 2005
that was 3-4 weeks earlier than in 2004. On Akimiski
Island, nesting phenology was the earliest on record
since 1993. Nest density there was the highest ever
recorded. Clutch sizes, and estimates of goslings
leaving nests in 2005 were the highest recorded
34
during 1993-2005. Indices of nest destruction in
2005 were 66% lower than in 2004. Although the
gosling production rate of SJBP geese will be much
improved over 2004, uncertainty of the breeding
population precludes estimation of the fall flight.
Year
'90 '91 '92 '93 '94 '95 '96 '97 '98 '99 '00 '01 '02 '03 '04 '05
Thousands
20
40
60
80
100
120
140
160
180
Fig. 7. Estimated total population (and 95% confidence intervals) of
Southern James Bay Population Canada geese during spring.
Mississippi Valley Population (MVP): The principal
nesting range of this population is in northern
Ontario, especially in the Hudson Bay Lowlands,
west of Hudson and James Bays. MVP Canada
geese primarily concentrate during fall and winter in
Wisconsin, Illinois, and Michigan (Fig. 3).
Breeding ground surveys conducted in 2005
indicated the presence of 344,900 (+ 49,200) MVP
breeding adults in 2005, 25% more than in 2004 (P =
0.087). Estimates of breeding adults have declined
an average of 2% per year during 1996-2005 (P =
0.242). Surveys indicated a total population of
539,300 (+ 104,400) Canada geese, a 26%
decrease from 2004 (P = 0.049, Fig. 8). There is no
evidence of a trend in these estimates since 1996 (P
= 0.97). Molt migrant Canada geese likely had little
impact on the total goose estimate this year.
Biologists used a different survey plane in 2005,
which in limited comparison flights yielded lower
estimates than the plane used previously. Spring
snowmelt occurred nearly a month earlier than in
2004 and much earlier than average. Despite
snowfall in late April, nesting conditions were
favorable and production is expected to be much
improved over the poor production of 2004. A fall
flight larger than that of 2004 is expected.
Year
'89 '90 '91 '92 '93 '94 '95 '96 '97 '98 '99 '00 '01 '02 '03 '04 '05
Thousands
100
200
300
400
500
600
Fig. 8. Estimated number (and 95% confidence intervals) of
Mississippi Valley Population breeding Canada geese during
spring.
Mississippi Flyway Giant Population (MFGP):
Giant Canada geese have been reestablished or
introduced in all Mississippi Flyway states. This large
subspecies now represents a significant portion of all
Canada geese in the Mississippi Flyway (Fig. 3).
Spring surveys in 2005, yielded an estimate of
1,583,100 MFGP geese, 1% lower than the final
2004 estimate of 1,600,700 (Fig. 9). These
estimates have increased an average of 5% per year
since 1996 (P < 0.001). Ohio expected major nest
losses due to a snowstorm in April. However, most
states expected average to above average
production in 2005, with especially good nesting
conditions in Ontario, Michigan, and Indiana. A large
fall flight, similar to that of 2004 is expected.
Year
'93 '94 '95 '96 '97 '98 '99 '00 '01 '02 '03 '04 '05
Thousands
600
800
1000
1200
1400
1600
1800
Fig. 9. Estimated number of Mississippi Flyway Giant Population
Canada geese during spring.
Eastern Prairie Population (EPP): These geese
nest in the Hudson Bay Lowlands of Manitoba and
concentrate primarily in Manitoba, Minnesota, and
Missouri during winter (Fig. 3).
35
The 2005 spring estimate of EPP geese was
254,700 (+ 30,900), 12% lower than the 2004
estimate (P = 0.142, Fig. 10). Spring estimates have
increased an average of 5% per year over the last 10
years (P = 0.047). The 2005 survey estimate of
singles and pairs was 161,600 (+ 21,100), 11%
higher than last year (P = 0.276). These estimates
have increased an average of 2% per year during
1996-2005 (P = 0.213). Spring phenology in 2005
was early to average in the southern portion, and
near average in the northern portion of EPP range.
This year, biologists on Cape Churchill observed a
median hatch date of 28 June, slightly later than the
long-term average (1976-2004). Nest density there
was the highest since 1990, but still below the long-term
mean. Mean clutch size (3.8 eggs) and the nest
success index were near the long-term average. A
fall flight larger than that of 2004 is expected.
Year
'72 '74 '76 '78 '80 '82 '84 '86 '88 '90 '92 '94 '96 '98 '00 '02 '04 '06
Thousands
50
100
150
200
250
300
350
Fig. 10. Estimated number (and 95% confidence intervals) of
Eastern Prairie Population Canada geese during spring.
Western Prairie and Great Plains Populations
(WPP/GPP): The WPP is composed of mid-sized
and large Canada geese that nest in eastern
Saskatchewan and western Manitoba. The GPP is
composed of large Canada geese resulting from
restoration efforts in Saskatchewan, North Dakota,
South Dakota, Nebraska, Kansas, Oklahoma, and
Texas. Geese from these breeding populations
commingle during migration with other Canada
geese along the Missouri River in the Dakotas and
on reservoirs from southwestern Kansas to Texas
(Fig. 3). These 2 populations are managed jointly
and surveyed during winter.
During the 2005 MWS, 415,100 WPP/GPP geese
were counted, 33% fewer than in 2004 (Fig. 11).
These indices have increased an average of 3% per
year since 1996 (P = 0.233). In 2005, the estimated
spring population in the portion of WPP/GPP range
included in the WBPHS was 592,100 (+ 86,500),
14% lower than last year (P = 0.204). The WBPHS
estimates have increased an average of 5% per year
since 1996 (P = 0.004). Goose production in the
WPP range likely was improved from 2004 due to
earlier snowmelt and improved wetland abundance.
Most states in the GPP range reported near average
nesting conditions and production. However, North
Dakota reported low Canada goose brood sizes
there, perhaps due to cold and wet weather during
the hatch period in North Dakota, a weather pattern
that also occurred in Saskatchewan. A fall flight
somewhat lower than that of last year is expected.
Year
'82 '84 '86 '88 '90 '92 '94 '96 '98 '00 '02 '04 '06
Thousands
0
100
200
300
400
500
600
700
800
Fig. 11. Estimated number of Western Prairie Population/Great
Plains Population Canada geese during winter.
Tall Grass Prairie Population (TGPP): These small
Canada geese nest on Baffin (particularly on the
Great Plain of the Koukdjuak), Southampton, and
King William Islands; north of the Maguse and
McConnell Rivers on the Hudson Bay coast; and in
the eastern Queen Maud Gulf region. TGPP Canada
geese winter mainly in Oklahoma, Texas, and
northeastern Mexico (Fig. 3). These geese mix with
other Canada geese on wintering areas, making it
difficult to estimate the size of the winter population.
During the 2005 MWS in the Central Flyway,
400,800 TGPP geese were counted, 13% fewer than
in 2004 (Fig. 12). These estimates have increased
an average of 6% per year during 1996-2005 (P =
0.229). Biologists report that the timing of snowmelt
during the spring of 2005 appeared to be earlier than
average near the McConnell River Sanctuary and
near average in the Queen Maud Gulf Sanctuary and
Southampton Island, but appeared to have been
delayed on King William and Baffin Islands by harsh
weather in late May and June. Limited information
suggests production of TGPP Canada geese will be
similar to that of 2004.
36
Year
'72 '74 '76 '78 '80 '82 '84 '86 '88 '90 '92 '94 '96 '98 '00 '02 '04 '06
Thousands
100
200
300
400
500
600
700
*
* Changes in survey coverage or methodology - not comparable with previous surveys
*
Fig. 12. Estimated number of Tall Grass Prairie Population Canada
geese in the Central Flyway during winter.
Short Grass Prairie Population (SGPP): These
small Canada geese nest on Victoria and Jenny Lind
Islands and on the mainland from the Queen Maud
Gulf west and south to the Mackenzie River and
northern Alberta. These geese winter in
southeastern Colorado, northeastern New Mexico,
and the Oklahoma and Texas panhandles (Fig. 3).
Year
'70 '72 '74 '76 '78 '80 '82 '84 '86 '88 '90 '92 '94 '96 '98 '00 '02 '04 '06
Thousands
0
100
200
300
400
500
600
700
800
Fig. 13. Estimated number of Short Grass Prairie Population
Canada geese during winter.
The MWS index of SGPP Canada geese in 2005
was 177,200, 13% lower than in 2004 (Fig. 13).
These indices have declined an average of 15% per
year since 1996 (P = 0.001). In 2005, the estimated
spring population of SGPP geese in the Northwest
Territories (WBPHS strata 13-18) was 116,700 (+
47,400), a 20% increase from 2004 (P = 0.529).
WBPHS estimates have increased an average of 3%
per year since 1996 (P = 0.446). Nesting phenology
of Canada geese and light geese are influenced by
many of the same factors. The timing of spring
snowmelt and nest initiation of light geese at Karrak
Lake was near average in 2005. Surveys on Victoria
Island and the mainland of the western Canadian
Arctic suggested an early snowmelt and good
Canada goose nesting efforts. Additionally, wetland
conditions in WBPHS strata 13-18 were considered
favorable for waterfowl nesting. Although specific
information is limited, production from SGPP geese is
expected to be average or better in 2005.
Hi-line Population (HLP): These large Canada
geese nest in southeastern Alberta, southwestern
Saskatchewan, eastern Montana and Wyoming, and
in Colorado. They winter in Colorado and in central
New Mexico (Fig. 3).
The 2005 MWS indicated a total of 207,400 HLP
Canada geese, 4% fewer than last year’s estimate
(Fig. 14). The MWS estimates have increased an
average of 4% per year since 1996 (P = 0.145). The
WBPHS yields an estimate of the HLP spring
population in Saskatchewan, Alberta, and Montana.
The 2005 WBPHS estimate was 236,200 (+ 49,400),
18% higher than the 2004 estimate (P = 0.320).
WBPHS population estimates have increased an
average of 1% per year during 1996-2005 (P =
0.530). Wyoming’s estimate of the HLP breeding
population there was 18,400, an increase of 16%
from 2004. Wetland abundance was relatively low
throughout most of HLP range at the end of last
winter and into spring. Substantial rainfall occurred in
May and June and improved wetland conditions, but
had an unknown impact regarding nest flooding and
gosling survival. The fall flight of HLP geese is
expected to be similar to that of 2004.
Year
'70 '72 '74 '76 '78 '80 '82 '84 '86 '88 '90 '92 '94 '96 '98 '00 '02 '04 '06
Thousands
0
50
100
150
200
250
300
Fig. 14. Estimated number of Hi-line Population Canada geese
during winter.
Rocky Mountain Population (RMP): These large
Canada geese nest in southern Alberta and western
Montana, and the inter-mountain regions of Utah,
Idaho, Nevada, Wyoming, and Colorado. They
winter mainly in central and southern California,
Arizona, Nevada, Utah, Idaho, and Montana (Fig. 3).
37
Spring population estimates from RMP states and
provinces in 2005 totaled 172,000, 8% higher than in
2004. These estimates have increased an average
of 3% per year during the last 10 years (P = 0.091,
Fig. 15). Although southern Alberta remains dry, late
winter and spring precipitation has been restoring
many U.S. RMP areas that have been subjected to
drought for several years. In some areas, spring
rains may have flooded nests, and cold, wet weather
during hatch may have reduced production in some
RMP areas. Colorado and Utah expected gosling
production to be reduced due to flooding. The fall
flight of RMP geese is expected to be similar to that
of last year.
Year
'70 '72 '74 '76 '78 '80 '82 '84 '86 '88 '90 '92 '94 '96 '98 '00 '02 '04 '06
Thousands
0
20
40
60
80
100
120
140
160
180
200
Fig. 15. Estimated number of Rocky Mountain Population Canada
geese during spring.
Pacific Population (PP): These large Canada
geese nest and winter west of the Rocky Mountains
from northern Alberta and British Columbia south
through the Pacific Northwest to California (Fig. 3).
Most PP geese are surveyed in Alberta and
Oregon. In 2005, survey indices in Alberta (WBPHS
strata 76-77) and Oregon were 44,400 and 41,900,
respectively. These indices represent declines of
25% (P = 0.507) and 19%, respectively from indices
in 2004. Breeding population indices declined in 3,
and increased in 2 other states or provinces.
California and British Columbia expected good to
excellent production. Wetland conditions improved in
Oregon, Montana, and Nevada due to spring rains in
2005, but the timing of rains may have reduced
goose productivity there. Consolidated assessment
of PP productivity or fall flight cannot be made with
the available information.
Dusky Canada Geese: These mid-sized Canada
geese predominantly nest on the Copper River Delta
of southeastern Alaska, and winter principally in the
Willamette and Lower Columbia River Valleys of
Oregon and Washington (Fig. 3).
The size of the population is estimated through
observations of marked geese during December and
January. The 2004-2005 population estimate was
21,800 (+ 4,600), 46% higher than in 2003-2004 (P =
0.020, Fig. 16). These estimates have increased an
average 3% per year during the last 10-year period
(P = 0.215). Preliminary results from the 2005 spring
survey of the Copper River Delta indicated the index
of singles and pairs increased 47%, and total dusky
Canada geese increased 58% from last year’s levels.
The 2005 total goose estimate exceeds the long-term
average (since 1986). Increases in population
indices were not unexpected in 2005, given good
nest success in 3 of the 4 previous years. In 2005,
the Copper River Delta experienced a warm spring,
with snowmelt and nesting phenology earlier than
average. However, preliminary results indicate nest
success was very low this year, perhaps the lowest
of the previous 9 years. A fall flight similar to that of
last year is expected.
Year
'70 '72 '74 '76 '78 '80 '82 '84 '86 '88 '90 '92 '94 '96 '98 '00 '02 '04 '06
Thousands
5
10
15
20
25
30
Fig. 16. Estimated number of dusky Canada geese during winter.
Cackling Canada Geese: Cackling Canada geese
nest on the Yukon-Kuskokwim Delta (YKD) of
western Alaska. They primarily winter in the
Willamette and Lower Columbia River Valleys of
Oregon and Washington (Fig. 3).
The primary index of this population was a fall
estimate from 1979-1998. Since 1999, the index has
been an estimate of the subsequent fall population
derived from spring counts of adults on the YKD.
The fall estimate for 2005 is 156,900, 21% higher
than that of 2004. These estimates have decreased
an average of 1% per year since 1996 (P = 0.478,
Fig. 17). Surveys in the coastal zone of the YKD
during spring 2005 indicated increased numbers of
single and paired cackling geese, and an increase of
27% in total birds from 2004 estimates. Spring
phenology on the YKD was about 1 week earlier than
average and mean hatching date for these geese
was 4 days earlier than average. YKD nesting
38
surveys indicated reductions in average clutch size
and nest success from the very good year of 2004.
A fall flight somewhat larger than that of last year
is expected.
Year
'80 '82 '84 '86 '88 '90 '92 '94 '96 '98 '00 '02 '04 '06
Thousands
0
20
40
60
80
100
120
140
160
180
200
220
Fig. 17. Number of cackling Canada geese estimated from fall and
spring surveys.
Lesser and Taverner’s Canada Geese: These
subspecies nest throughout much of interior and
south-central Alaska and winter in Washington,
Oregon, and California (Fig. 3). Taverner’s geese
are more associated with the North Slope and tundra
areas, while lesser Canada geese tend to nest in
Alaska’s interior. However, these subspecies mix
with other Canada geese throughout the year and
reliable estimates of separate populations are not
presently available.
The estimated number of Canada geese within
WBPHS strata predominantly occupied by these
geese (strata 1-6, 8, 10-12) in 2005 decreased 2%
from 2004 levels. These estimates have declined an
average of 4% per year since 1996 (P = 0.084). In
Alaska’s interior, spring breakup varied from average
to 2 weeks earlier than average. The Koyukuk and
other central Alaska rivers experienced widespread
and prolonged flooding, and the nesting of lesser
Canada geese there was redistributed but
successful. Spring snowmelt on the North Slope was
the latest observed in many years and production of
Taverner’s geese there is expected to be poor.
Aleutian Canada Geese (ACG): The Aleutian
Canada goose was listed as endangered in 1967
(the population numbered approximately 800 birds in
1974) and was delisted in 2001. These geese now
nest primarily on the Aleutian Islands, although
historically they nested from near Kodiak Island,
Alaska to the Kuril Islands in Asia. They now winter
along the Pacific Coast to central California (Fig. 3).
The population estimate based on observations of
neckbanded geese in California during 2004-2005
was 63,800 (+ 12,400), 9% lower than last year’s
record high estimate (P = 0.555, Fig. 18). These
indirect estimates have increased an average of 12%
per year over the last 10 years (P < 0.001). The
Aleutian Islands experienced light winter snowfall and
an early spring breakup again in 2005. Nesting
phenology for Aleutian Canada geese was similar to
2004, which was the earliest on record. Clutch sizes
were near average and another large fall flight,
similar to that of 2004 is expected.
Year
'74 '76 '78 '80 '82 '84 '86 '88 '90 '92 '94 '96 '98 '00 '02 '04 '06
Thousands
0
10
20
30
40
50
60
70
Fig. 18. Number of Aleutian Canada geese estimated from
winter estimates and mark-resight methods.
Status of Light Geese
The term light geese refers to both snow geese
and Ross’ geese (including both white and blue
color phases), and the lesser (C. c. caerulescens)
and greater (C. c. atlantica) snow goose
subspecies. Another collective term, mid-continent
light geese, includes lesser snow and
Ross’ geese of 2 populations: the Mid-continent
Population and the Western Central Flyway
Population.
Ross’ Geese: Most Ross’ geese nest in the Queen
Maud Gulf region, but increasing numbers nest along
the western coast of Hudson Bay, and Southampton,
Baffin, and Banks Islands. Ross’ geese are present
in the range of 3 different populations of light geese
and primarily winter in California, New Mexico,
Texas, and Mexico, with increasing numbers in
Louisiana and Arkansas (Fig. 19).
Periodic photo-inventories and annual surveys in
the Queen Maud Gulf indicate the spring Ross’
goose population has increased rapidly and by 2000
had exceeded 800,000 adult geese. Comprehensive
annual estimates of total population size are not
available, but surveys on wintering and breeding
areas indicate increases in range, number, and
proportions of Ross’ geese. The proportion of
39
Atlantic
Brant
Pacific
&
WHA Brant
Fig. 19. Approximate ranges of brant and snow, Ross', and white-fronted goose populations in North America.
Pacific Mid-continent
Populations of Greater
White-fronted Geese
Mid-continent
Western Central
Flyway
Populations of
Light Geese
Wrangel
Island
Populations of
Brant
Ross'
Geese
Greater
Snow
Geese
Western
Arctic
Populations of
Light Geese
40
Ross’ geese, assessed annually throughout the
wintering range of the Western Central Flyway
Population, has increased since 1984 (Fig. 20), while
the total population has also increased (see Western
Central Flyway Light Geese below). The largest
Ross’ goose colonies are near Karrak Lake in the
Queen Maud Gulf. Researchers have estimated an
11% average annual growth rate of Ross’ geese at
Karrak Lake during 1995-2003 (433,800 adult Ross’
geese there in 2003). An adjacent colony has grown
to contain similar numbers of Ross’ geese. The
timing of snowmelt, nesting phenology, and weather
during incubation at Karrak Lake was near average in
2005. Numbers of Ross’ geese nesting near the
McConnell River and at La Perouse Bay continued to
increase in 2005. The 2005 estimate of nesting
adults at the McConnell River, approaching 100,000,
was approximately 12% and 25% higher than in
2004 and 2003, respectively. Spring phenology was
near average in 2005; nesting ground conditions
were wet due to heavy winter snowfall. Few foxes
were observed and nest success appeared to be
high there. Spring phenology on Southampton Island
was reportedly near average. Overall, Ross’ geese
are expected to experience average or above
average production this year. The size of the fall
flight cannot be predicted without an annual index to
the size of the total breeding population.
Year
'84 '86 '88 '90 '92 '94 '96 '98 '00 '02 '04
Percent Ross' geese
0
20
40
Fig. 20. Estimated proportion of Ross’ geese in the Western
Central Flyway Population, 1984-2004.
Mid-continent Population Light Geese (MCP): This
population includes lesser snow geese and
increasing numbers of Ross’ geese. The MCP nest
on Baffin and Southampton Islands, with smaller
numbers nesting along the west coast of Hudson Bay
(Fig. 19). These geese winter primarily in eastern
Texas, Louisiana, and Arkansas.
During the 2005 MWS, biologists counted
2,339,400 light geese, 9% more than last year (Fig.
21, a portion of Louisiana was not surveyed in 2004).
Due to declines in these indices since 1997, the
1996-2005 data now indicate an average decline of
2% per year (P = 0.088). Survey biologists on Baffin
Island during mid-June 2005 observed extensive
snow cover and expected a reduced nesting effort
there. Spring phenology was reportedly near
average on Southampton Island and average
production was expected. Spring phenology at Cape
Henrietta Maria was earlier than average and good
snow goose production is expected. At La Perouse
Bay, nesting phenology was near average, but nest
density in 2005 was nearly double that of the recent
average. Clutch sizes were above average.
However, temperatures during the incubation period
had been well below average and goose forage
plants had not begun above-ground growth 4 days
prior to the hatching period. Biologists expressed
concern about gosling survival under those
conditions. Considering the potentially reduced
nesting effort on Baffin Island, where most MCP
geese nest, no better than average overall production
is expected. However, unlike last year, migration
habitats were in favorable condition in 2005, and the
fall flight should be improved over that of 2004.
Year
'70 '72 '74 '76 '78 '80 '82 '84 '86 '88 '90 '92 '94 '96 '98 '00 '02 '04 '06
Thousands
500
1000
1500
2000
2500
3000
3500
Fig. 21. Estimated number of Mid-continent Population light geese
(lesser snow and Ross’ geese) during winter.
Western Central Flyway Population (WCFP): This
population is composed primarily of snow geese but
includes a substantial proportion of Ross’ geese.
WCF geese nest in the central and western
Canadian Arctic, with large nesting colonies near the
Queen Maud Gu