Waterfowl breeding population and habitat survey for southern and central Alberta

              WATERFOWL BREEDING POPULATION SURVEY
SOUTHERN AND CENTRAL ALBERTA
MAY 2001
FORT
ST. JOHN
PEACE
RIVER
GRANDE PRAIRIE SLAVE LAKE
LAC LABICHE
COLD LAKE
EDMONTON
VERMILION
RED DEER
HANNA
CALGARY
BROOKS
MEDICINE HAT
LETHBRIDGE
76
75
26
27
28
29
TITLE Waterfowl Breeding Population and Habitat Survey for Southern and Central
Alberta
STRATA SURVEYED 26, 27, 28, 29, 75, 76
DATES May 3-22, 2001
DATA SUPPLIED BY United States Fish and Wildlife Service (USFWS)
Canadian Wildlife Service (CWS)
Alberta Environmental Protection/Wildlife
Management Division (AEP)
Ducks Unlimited, Canada (DUC)
Aerial Crew
Pilot/Observer-Elizabeth Buelna, USFWS, Flyway Biologist
Observer-(St26-29, 75)Alan Davenport, USFWS, Computer Specialist
Observer-(St.76)Dave Duncan, CWS, Population Mgmt. Biologist
Ground Crew
Crew Leaders-
Dave Duncan, CWS, Population Mgmt., Biologist
Paul Pryor, CWS, Population Mgmt. Technician
Ken Froggatt, Alberta Natural Resources Service, Wildlife Technician
Sam Berry, CWS, Biometrician
Ed Hoffman, Alberta Natural Resources Service, Wildlife Biologist
Assistants-
Reg Russell, Alberta Natural Resources Service, WildlifeTechnician
Brian Peers, DUC,Wildlife Biologist
Trevor Mathews, Ducks Unlimited, Biological Technician
Mark Johnson, CWS, Student Technician
Lisa Crowe, CWS, Student Technician
Chris Procter, CWS, Student Technician
Jason Spenst, CWS, Student Technician
Suzanne Witham, DUC, Resource Specialist
Mike Barr, DUC, Wildlife Biologist
ABSTRACT
The 2001 breeding population estimate for strata 26-29 (Southern Alberta) is 2,531,100 total
ducks (Table 1), a decrease of -27.50% from 2000, a decrease of -26.1% from the recent ten-year
mean (1991-2000) and a decrease of -43.5% from the long-term mean (1955-2000). In Southern
Alberta, total dabbling ducks (Table 1) decreased -26.4% from 2000, -23.2% from the 1991-
2000 ten-year mean and remained -44.4% below the 1955-2000 long-term mean. Mallards
(Table 1) decreased -10.7% from 2000, Blue-winged Teal decreased -36.4% from 2000 and
Pintails decreased -65% from 2000. Total diving ducks (Table 1) decreased -33.2% from 2000,
decreased -37.4% from the 1991-2000 ten-year mean and decreased -38.8% from the 1955-2000
long-term mean. Total pond
counts (Table 2) decreased -23% in Southern Alberta from last year, -40.3% from the ten- year
and -42.2% from the long term means.
The 2001 breeding population estimate for strata 75-76 (Central Alberta) is 1,479,400 total ducks
(Table 4). In Central Alberta, total ducks(Table 4) decreased -17.9% from last year and
increased +1.7% from the long-term(12 year) mean. Total dabbling ducks decreased -30.5%
from last year and decreased -2.1% from the 12-year mean. Mallards decreased -2.6% from
2000, and increased +20% from the 12-year mean. Blue-winged Teal decreased -69.2% from
last year and decreased -46.1% from the 12-year mean. Pintails decreased -45.2% from 2000
and decreased -70.4% from the 12-year mean. Total diving ducks increased +13.5% from last
year and increased +5.1% from the 12-year mean. Total ponds (Table 5) in Stratum 75 and 76
decreased -5% from last year and decreased -15.6% from the 12-year mean.
The fall, winter and spring in Southern and Central Alberta saw below normal precipitation in
the majority of the province. Winter temperatures were normal to slightly above normal for all
areas. The mountain snow pack was 35-50% of normal in Southern and Central Alberta. By
June 1, a much below normal spring runoff in the prairies was complete and most of the
snowpack had been depleted.. As of May 1 , 22% of the agriculture land in Alberta was in the
very low spring soil moisture category and 68% of the land was in the low category.
Precipitation in May was generally below-average in most areas of the province. Current
predictions from Environment Canada are for below-normal precipitation for the June to August
period in southern Alberta.
METHODS
The procedures followed in conducting the survey are contained in the Standard Operating
Procedures for Aerial Waterfowl Breeding Ground Population and Habitat Surveys, Section III,
revised April 1987. The analytical and procedural changes, described in the 1991 and 1992
reports, continued this year. As a result, measures of precision are now available with the
population estimates. This years and the last four years reports reflects a major change made to
the historical (1955-1995) database of breeding waterfowl and habitat estimates. Nonparametric
regression methods were used to predict population values for years in which no survey was
conducted in a stratum. An internal report (Office of Migratory Bird Management, Laurel, MD)
describes how and for which cases prediction was done.
Air-ground segment data in Central Alberta's strata 75 and 76(12- air/ground segments = 13% of
the survey area) are not sufficient to compute accurate visibility correction factors (VCF's) for all
duck species. Stratum 26 more closely resembles the habitat of 75 and 76 than the other
Southern Alberta strata (27-29). It was decided to combine air-ground data from strata 26, 75
and 76, when calculating VCF's for strata 75 and 76. Acceptable standard errors and variances
were obtained when this was done. Southern Alberta VCF's are still calculated with data from
strata 26-29 only (37- air/ground segments = 25% of the survey area).
In 1996, Canada goose breeding population estimates were corrected for visibility bias based on
data collected by air and ground survey crews in this reporting region. For validity of
comparisons to means for previous years, historical Canada goose population indices were also
adjusted for visibility bias using data collected by all air and ground survey crews throughout the
Canadian and U.S. prairie regions in 1996. Therefore, estimates and means reported here cannot
be directly compared with those in reports written before 1996 for this region.
Air data were compiled using a notebook computer. All areas in the current survey design
(Tables 3 and 6) were flown. The survey was conducted using the same aerial crew and aircraft,
a Cessna 206, for strata 26-29, and 75. This was the 14th year of flying aerial waterfowl
surveys for the aerial crew. An experienced aerial observer , CWS Biologist Dave Duncan was
the aerial observer for strata 76. All air and ground crew members participated in pre-survey
training.
The Alberta ground crew did reconnaissance of the survey area and concluded that most species
observed appeared paired. Most deciduous tree species were leafed out and the season timing
appeared normal in southern areas . The survey was initiated on May 3 for Southern Alberta
and completed on May 15. The Central Alberta survey commenced on May 14 and concluded on
May 22. A total of 65 flight hours was required to complete the survey. Aerial Canvasback
telemetry was conducted in conjunction with the waterfowl survey when logistics allowed. Data
was forwarded to USGS, Dixon, CA.
WEATHER AND HABITAT CONDITIONS
Environment Canada, Climate Research Branch reports average to slightly above average
temperatures for the November 2000 to April 2001 period . Spring in Southern and Central
Alberta saw below normal precipitation in all areas.. Temperatures were average and
precipitation in May was generally below-average in most areas of the province.
The Milk River country along the Montana border was in poor condition. Most of the Prairie
Grassland portions of strata 27, 28 and 29 were in fair to poor condition. Dug out levels (some
of the only remaining water) were in the dry , to 1/4 full level in the southern portions of the
Prairie grasslands
The Aspen Parklands of Stratum 26 were mostly in fair condition with areas of good condition
in a 20 mile radius around Edmonton and Red Deer. Dugout levels were in the ½ full level.
The Ag Forest Transition and Parklands of stratum 75 and 76 were generally in poor condition.
The more permanent type wetlands available in these areas were in poor condition compared to
1999, but in slightly better condition than 2000. Scars from the 1998 fires are still visible
(250,000+ hectares of tundra and forest burned in the Slave Lake and Swan Hills portions of
Stratum 75) plus new fires in this area were adding to the destruction of the parklands.
BREEDING POPULATION INDICES
When comparing birds to the current ten-year mean (1991-2000), it is important to remember the
1980's were characterized by decreasing waterfowl populations and habitat conditions. A listing
of all birds and the respective comparisons can be found in Tables 1 and 4, the Trend Graphs and
Appendices 1 and 2.
SOUTHERN ALBERTA
The 2001 breeding population estimate for strata 26-29 (Southern Alberta) is 2,531,100 total
ducks (Table 1), a decrease of -27.50% from 2000, a decrease of -26.1% from the recent ten-year
mean (1991-2000) and a decrease of -43.5% from the long-term mean (1955-2000). In Southern
Alberta, total dabbling ducks (Table 1) decreased -26.4% from 2000, -23.2% from the 1991-
2000 ten-year mean and remained -44.4% below the 1955-2000 long-term mean. Mallards
(Table 1) decreased -10.7% from 2000, decreased -11.2% from the 10-year mean and decreased -
35% from the long term means. Blue-winged Teal decreased -36.4% from 2000 , decreased -
27.5% from the 10-year mean, and decreased -41.8% from the long-term means. Pintails
decreased -65% from 2000, decreased -73% from the 10-year mean and decreased -91% from
the long-term mean. Total diving ducks (Table 1) decreased -33.2 % from 2000, decreased -
37.4% from the 1991-2000 ten-year mean and decreased -38.8% from the 1955-2000 long-term
mean. Total pond counts (Table 2) decreased -23% in Southern Alberta from last year, -40.3%
from the ten- year and -42.2% from the long term means. Canada geese numbers changed -
20.8%, +50.1% and +251.6%, and Coots changed -50.5%, -30.2 and -9.3% from the above
respective means.
Overall mallard breeding population estimates for( Prairie Canada and north central U.S.)
regions in the traditional survey areas decreased -17% from last year and were up +5% from the
long-term averages.. Survey timing appeared good for Blue-winged Teal this year. Overall
Blue-winged teal breeding population estimates for( Prairie Canada and north central U.S.)
regions in the traditional survey areas declined -23% from last year and were up +29% from the
long-term averages. Overall Pintail breeding population estimates for( Prairie Canada and north
central U.S.) regions in the traditional survey areas increased +13% from last year and were
down -23% from the long-term averages. Total duck breeding population estimates for regions
in the traditional survey areas decreased -14% from last year and were up +9 from the long -term
averages.
CENTRAL ALBERTA
The 2001 breeding population estimate for strata 75-76 (Central Alberta) is 1,479,400 total ducks
(Table 4). In Central Alberta, total ducks(Table 4) decreased -17.9% from last year and
increased +1.7% from the long-term(12 year) mean. Total dabbling ducks decreased -30.5%
from last year and decreased -2.1% from the 12-year mean. Mallards decreased -2.6% from
2000, and increased +20% from the 12-year mean. Blue-winged Teal decreased -69.2% from
last year and decreased -46.1% from the 12-year mean. Pintails decreased -45.2% from 2000
and decreased -70.4% from the 12-year mean. Total diving ducks increased +13.5% from last
year and increased +5.1% from the 12-year mean. Total ponds (Table 5) in Stratum 75 and 76
decreased -5% from last year and decreased -15.6% from the 12-year mean.
CONCLUSIONS
1) Poor habitat conditions and drought seem to be the continued trend again in Alberta this year.
Ducks appeared crowded in the few remaining wetlands. This intense competition for nesting
territories will likely have a negative effect on nesting success.
2) In 84 years of record , 2001 has been estimated at the 6th driest on record. Long term average
pond counts were down -42% in Southern and -16% in Central Alberta. Soil moisture conditions
were very low through out the province.
3) Waterfowl numbers declined in the Aspen Parklands of Stratum 26, which is normally the
bright spot for waterfowl numbers and abundance of wetlands and nesting habitat.
Sincere appreciation is extended to all who participated in this survey. Thank you to the
Winnipeg Climate Center and Alberta Agriculture for precipitation data and soil moisture maps.
Submitted by: Elizabeth Buelna-Flyway Biologist Date: June 27, 2001
Table 1. Status of waterfowl breeding population estimates (thousands, adjusted for visibility bias) by species and stratum with
comparison against the previous year, the previous 10-year mean, and the long-term mean for Southern Alberta.
Stratum % Change From
Species/Ponds 26 27 28 29 2001 Total 2000 Total 10-Year
Mean
Long-Term
Mean
2000 10-Year
Mean
Long-Term
Mean
Ducks
Dabblers
Mallard 461.1 100.0 111.1 71.6 743.8 833.2 837.6 1143.4 -10.7% -11.2% -35.0%
Am. black duck 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 -- -- -100.0%
Gadwall 199.4 23.1 25.2 9.0 256.8 310.9 370.3 310.5 -17.4% -30.7% -17.3%
Am. wigeon 72.9 28.3 47.6 38.0 186.8 225.2 179.6 314.8 -17.0% 4.0% -40.7%
Am. green-winged teal 117.3 30.9 38.6 3.7 190.5 308.1 210.9 199.1 -38.2% -9.7% -4.3%
Blue-winged teal 290.2 40.1 23.9 13.6 367.8 577.8 507.6 632.4 -36.4% -27.5% -41.8%
N. shoveler 179.3 27.3 25.0 36.2 267.8 380.4 358.1 357.4 -29.6% -25.2% -25.1%
N. pintail 32.0 12.3 10.2 11.6 66.1 188.8 245.1 781.6 -65.0% -73.0% -91.5%
Subtotal 1352.2 262.0 281.6 183.6 2079.5 2824.4 2709.3 3739.2 -26.4% -23.2% -44.4%
Divers
Redhead 31.3 2.3 7.0 13.4 54.0 106.8 118.5 119.6 -49.5% -54.5% -54.9%
Canvasback 24.5 1.8 3.5 2.1 31.9 73.2 59.5 66.0 -56.4% -46.4% -51.7%
Scaups 148.3 29.7 18.2 5.8 201.9 292.3 297.5 374.9 -30.9% -32.1% -46.1%
Ring-necked duck 12.2 3.3 3.6 1.1 20.2 16.2 18.9 17.2 24.3% 6.6% 17.4%
Goldeneyes 21.3 0.0 0.7 0.6 22.6 26.5 16.7 14.1 -14.9% 35.5% 60.1%
Bufflehead 55.5 1.6 1.2 0.9 59.2 70.9 74.8 47.3 -16.6% -20.9% 25.2%
Ruddy Duck 31.0 3.3 5.3 12.0 51.6 74.3 119.1 82.2 -30.5% -56.7% -37.2%
Subtotal 324.1 41.9 39.5 35.9 441.3 660.3 705.0 721.2 -33.2% -37.4% -38.8%
Miscellaneous
Oldsquaw 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 -- -100.0% -100.0%
Eiders 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 -- -- --
Scoters 1.8 0.0 0.0 0.0 1.8 0.0 3.9 13.9 -- -52.5% -86.9%
Mergansers 7.8 0.0 0.6 0.0 8.5 5.1 8.2 6.7 67.4% 3.3% 25.9%
Subtotal 9.7 0.0 0.6 0.0 10.3 5.1 12.1 20.7 103.6% -14.8% -50.2%
Total Ducks 1685.9 303.9 321.8 219.5 2531.1 3489.7 3426.4 4481.1 -27.5% -26.1% -43.5%
Canada Goose 122.8 27.8 32.4 30.4 213.5 269.5 142.2 60.7 -20.8% 50.1% 251.6%
Am. coot 97.2 37.4 30.4 42.3 207.4 418.8 297.0 228.8 -50.5% -30.2% -9.3%
Ponds 226.4 67.6 56.6 75.1 425.7 553.1 713.1 736.0 -23.0% -40.3% -42.2%
Table 2. Long term-trend in adjusted May pond estimates (thousands) by stratum with
comparisons against the previous year, the previous 10-year mean, and the long-term mean for
Southern Alberta.
Stratum
Year 26 27 28 29 Total
1961 358.2 105.8 82.0 49.8 595.7
1962 395.5 84.9 73.2 52.5 606.2
1963 543.0 127.9 49.1 57.6 777.6
1964 366.7 97.1 62.1 118.6 644.5
1965 601.7 197.5 95.5 104.2 998.8
1966 490.2 162.6 134.9 76.2 863.9
1967 377.5 155.9 215.8 169.9 919.1
1968 266.1 43.6 47.3 80.9 438.0
1969 483.2 156.4 125.3 94.5 859.5
1970 531.2 187.1 86.5 77.8 882.7
1971 585.4 196.6 121.4 78.0 981.4
1972 517.1 92.7 60.1 61.2 731.1
1973 683.9 136.4 121.3 83.6 1025.2
1974 947.3 259.1 124.1 64.1 1394.6
1975 428.2 205.8 178.3 145.6 957.9
1976 459.6 144.2 104.1 123.7 831.6
1977 433.8 53.0 45.4 55.8 588.0
1978 295.8 89.8 88.6 145.6 619.9
1979 617.2 124.9 100.7 153.7 996.4
1980 281.2 68.1 59.1 52.1 460.6
1981 365.2 80.5 58.9 64.7 569.3
1982 374.6 86.4 66.8 103.3 631.1
1983 318.7 56.0 58.0 64.3 497.1
1984 386.4 69.8 42.9 38.8 537.9
1985 493.5 170.2 89.3 75.3 828.3
1986 514.5 70.7 46.4 96.0 727.5
1987 325.0 151.5 58.1 72.1 606.8
1988 229.3 61.6 52.7 74.3 417.9
1989 274.0 111.2 57.8 105.9 548.9
1990 467.9 116.4 66.2 121.7 772.1
1991 445.7 83.1 73.5 93.4 695.7
1992 328.1 78.3 48.0 48.8 503.2
1993 344.0 139.1 90.7 115.9 689.8
1994 406.1 122.5 69.8 122.0 720.4
1995 417.9 93.2 58.8 118.8 688.7
1996 522.1 138.4 130.5 112.9 903.9
1997 653.6 199.0 143.2 104.6 1100.4
1998 358.1 78.7 66.3 56.2 559.3
1999 469.5 104.6 67.2 74.7 716.0
2000 345.9 89.3 63.1 54.8 553.1
2001 226.4 67.6 56.6 75.1 425.7
10-year Mean 429.1 112.6 81.1 90.2 713.1
Long-term Mean 442.6 119.8 84.6 89.1 736.0
Percent Change:
From 2000 -34.5% -24.4% -10.3% 37.0% -23.0%
From 10-year Mean -47.2% -40.0% -30.2% -16.7% -40.3%
From Long-term Mean -48.8% -43.6% -33.1% -15.7% -42.2%
Table 3. Survey design for Southern Alberta, May 2001.
STRATUM
26 27 28 29 Total
Survey design
Square miles in stratum 26,448 11,724 12,890 13,235 64,297
Square miles in sample-waterfowl 544.5 288.0 310.5 171.0 1,314
Square miles in sample-ponds 272.3 144.0 155.25 85.5 657
Lineal miles in sample 2,178 1,152 1,242 684 5,256
Number of transects in sample 11 6 7 4 28
Number of segments in sample 121 64 69 38 292
Expansion factor 48.5730 40.7083 41.5137 77.3977 ---
Current year coverage
Square miles in sample-waterfowl 256.5 144.0 130.5 171.0 697.5
Square miles in sample-ponds 126.0 72.0 65.25 85.5 348.75
Lineal miles in sample 1,008 576 522 684 2,790
Number of transects in sample 6 3 3 4 16
Number of segments in sample 57 32 29 38 155
Expansion factor 103.11 81.4167 98.7739 77.3977 —
Table 6. Survey design for Central Alberta, May 2001
STRATUM
75 76 Total
Survey design
Square miles in stratum 19,387 26,483 45,870
Square miles in sample-waterfowl 166.5 220.5 387
Square miles in sample-ponds 83.25 110.25 193.5
Lineal miles in sample 666 882 1,548
Number of transects in sample 4 5 9
Number of segments in sample 37 49 86
Expansion factor 116.4384 120.1043 --
Current year coverage
Square miles in sample-waterfowl 180.0 220.5 400.5
Square miles in sample-ponds 90.0 110.25 200.25
Lineal miles in sample 720 882 1602
Number of transects in sample 4 5 9
Number of segments in sample 40 49 89
Expansion factor 107.7056 120.1043
Appendix 1. Long-term trend in adjusted waterfowl breeding population estimates (thousands) for Southern Alberta.
Species/Ponds 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964
Ducks
Dabblers
Mallard 1907.0 1757.6 1986.7 2072.2 1753.0 1502.4 1330.9 983.1 1227.9 1119.4
Am. black duck 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
Gadwall 200.3 269.9 187.1 219.6 275.7 369.2 279.6 207.8 198.8 256.6
Am. wigeon 582.3 535.6 535.8 548.9 616.0 539.9 502.3 380.1 315.2 346.3
Am. green-winged teal 351.3 182.2 186.2 205.1 324.4 262.3 320.6 63.4 72.8 114.6
Blue-winged teal 1550.2 903.8 908.6 1078.5 903.6 877.8 897.1 346.7 426.8 634.6
N. shoveler 397.2 405.0 349.8 442.3 321.1 431.9 303.5 196.8 378.0 342.0
N. pintail 1591.5 1521.5 1250.6 1223.9 832.6 1087.5 513.3 328.6 811.9 417.6
Subtotal 6579.8 5575.5 5404.8 5790.4 5026.5 5071.0 4147.3 2506.6 3431.5 3231.1
Divers
Redhead 140.5 145.7 105.9 127.2 113.2 71.3 78.1 44.3 79.6 88.6
Canvasback 96.2 98.7 100.6 168.7 78.1 58.3 63.9 54.6 77.6 83.8
Scaups 427.2 483.2 515.1 490.6 400.2 325.8 393.6 231.9 358.5 400.5
Ring-necked duck 1.4 8.8 1.5 4.5 9.4 2.9 10.1 2.1 1.7 3.4
Goldeneyes 16.0 21.1 15.5 9.1 8.7 11.4 11.2 7.9 2.4 5.9
Bufflehead 26.1 36.6 33.8 39.5 44.6 32.9 53.2 22.1 26.5 24.4
Ruddy Duck 76.2 78.3 43.4 51.6 79.2 97.9 49.8 21.9 37.4 93.0
Subtotal 783.7 872.4 815.8 891.1 733.5 600.4 660.0 384.9 583.8 699.5
Miscellaneous
Oldsquaw 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
Eiders 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
Scoters 0.0 28.0 21.6 20.6 26.9 18.9 25.6 25.2 16.4 17.1
Mergansers 0.0 0.0 0.0 5.9 4.0 1.2 0.4 0.0 0.0 1.6
Subtotal 0.0 28.0 21.6 26.5 30.9 20.1 26.0 25.2 16.4 18.7
Total Ducks 7363.6 6475.9 6242.1 6708.1 5790.9 5691.5 4833.3 2916.7 4031.7 3949.3
Canada Goose 0.0 0.7 17.2 35.4 31.2 50.6 37.9 24.7 34.1 38.0
Am. coot 141.3 108.0 56.6 98.1 169.8 120.1 92.9 19.7 82.2 40.0
Ponds 595.7 606.2 777.6 644.5
Species/Ponds 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974
Ducks
Dabblers
Mallard 893.9 1546.7 1502.4 912.0 1121.4 1594.6 1871.3 1825.3 1729.5 1576.2
Am. black duck 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
Gadwall 200.3 479.6 415.8 491.6 339.0 343.3 362.8 444.9 281.0 495.6
Am. wigeon 320.9 385.5 485.3 467.5 403.8 434.3 502.0 448.4 394.1 514.5
Am. green-winged teal 117.2 176.1 175.0 121.5 204.5 203.6 263.3 288.1 311.9 404.8
Blue-winged teal 494.1 533.2 712.9 325.3 363.2 440.9 714.3 494.9 459.2 1209.7
N. shoveler 276.2 470.8 538.5 394.6 433.3 329.1 423.6 435.7 466.1 588.0
N. pintail 777.1 1265.2 1559.5 501.6 1584.5 1366.4 1763.1 1716.4 1025.1 2123.1
Subtotal 3079.8 4857.2 5389.4 3214.1 4449.8 4712.1 5900.4 5653.8 4666.9 6911.9
Divers
Redhead 93.3 190.1 194.4 85.0 117.8 74.7 68.7 118.1 89.1 155.3
Canvasback 100.5 68.5 97.9 57.9 26.7 49.4 39.0 65.5 54.0 100.2
Scaups 306.5 238.7 346.8 234.0 350.9 367.9 299.5 426.8 588.9 368.6
Ring-necked duck 11.0 4.3 34.8 11.0 8.7 14.2 36.2 30.6 2.0 15.1
Goldeneyes 1.5 4.9 0.0 5.6 8.9 3.6 20.4 15.6 19.7 17.7
Bufflehead 71.1 33.4 48.6 32.4 44.1 40.4 33.8 53.3 30.6 26.0
Ruddy Duck 93.4 83.0 111.9 96.7 47.9 66.9 56.7 102.0 38.2 93.3
Subtotal 677.3 623.0 834.4 522.7 605.0 617.1 554.4 811.9 822.5 776.3
Miscellaneous
Oldsquaw 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
Eiders 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
Scoters 16.9 20.0 23.6 17.5 21.6 23.2 12.1 13.2 16.0 8.0
Mergansers 9.3 7.7 1.8 1.1 1.7 9.4 4.1 4.2 2.1 0.0
Subtotal 26.1 27.7 25.4 18.6 23.3 32.7 16.1 17.4 18.1 8.0
Total Ducks 3783.3 5507.9 6249.2 3755.4 5078.0 5361.9 6470.9 6483.0 5507.5 7696.2
Canada Goose 24.0 19.0 34.6 15.0 23.5 28.4 50.0 30.5 35.7 29.2
Am. coot 65.1 48.1 202.5 98.8 144.8 169.8 99.7 122.6 145.4 267.0
Ponds 998.8 863.9 919.1 438.0 859.5 882.7 981.4 731.1 1025.2 1394.6
Appendix 1 (continued). Long-term trend in adjusted waterfowl breeding population estimates (thousands) for Southern Alberta.
Species/Ponds 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984
Ducks
Dabblers
Mallard 1398.3 1453.6 853.3 823.5 983.1 975.2 947.1 765.8 845.6 713.0
Am. black duck 0.0 0.0 0.0 0.0 0.0 0.0 0.3 0.0 0.0 0.0
Gadwall 303.7 308.7 392.2 279.7 346.4 319.6 309.4 215.5 142.3 204.4
Am. wigeon 384.3 344.5 194.9 303.5 402.5 403.9 179.8 200.0 170.9 158.4
Am. green-winged teal 230.8 345.6 151.9 222.3 256.8 224.0 180.1 127.5 136.2 117.7
Blue-winged teal 1108.2 820.3 751.0 393.2 592.9 834.6 1148.1 498.1 419.1 429.2
N. shoveler 550.3 325.0 220.8 259.0 391.4 388.8 503.9 320.4 200.3 187.3
N. pintail 1553.1 956.5 345.8 1087.6 1456.4 842.3 657.3 576.8 380.8 299.8
Subtotal 5528.7 4554.3 2909.8 3368.7 4429.5 3988.3 3926.1 2704.1 2295.1 2109.9
Divers
Redhead 181.7 173.4 202.1 133.8 100.7 268.4 111.1 57.8 60.4 98.3
Canvasback 78.9 52.1 64.6 51.2 53.5 62.1 49.4 73.8 49.7 26.6
Scaups 382.7 625.9 477.7 463.0 687.5 473.0 469.3 522.1 491.9 367.5
Ring-necked duck 26.0 13.5 23.9 50.9 21.3 8.9 29.5 23.7 12.7 33.6
Goldeneyes 15.5 28.3 3.9 33.2 7.6 29.6 4.6 6.8 6.8 1.7
Bufflehead 56.1 47.3 35.2 60.6 67.2 32.3 55.5 42.2 57.4 25.8
Ruddy Duck 184.7 33.6 101.5 75.5 42.0 33.9 63.0 116.0 72.9 62.3
Subtotal 925.7 974.1 908.9 868.3 979.7 908.2 782.5 842.4 751.8 615.8
Miscellaneous
Oldsquaw 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.6 0.0 0.0
Eiders 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
Scoters 7.3 24.1 13.5 26.0 36.2 20.4 7.7 11.8 6.4 17.3
Mergansers 16.4 0.0 4.8 16.1 5.7 18.0 13.6 15.5 15.3 4.9
Subtotal 23.8 24.1 18.3 42.1 41.9 38.3 21.3 27.9 21.7 22.2
Total Ducks 6478.2 5552.5 3837.0 4279.1 5451.1 4934.9 4729.8 3574.4 3068.6 2748.0
Canada Goose 30.2 19.8 23.8 30.2 35.5 21.1 45.6 40.3 41.7 46.8
Am. coot 483.3 83.5 285.4 168.4 418.0 501.1 405.0 371.7 253.2 542.7
Ponds 957.9 831.6 588.0 619.9 996.4 460.6 569.3 631.1 497.1 537.9
Species/Ponds 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994
Ducks
Dabblers
Mallard 803.0 698.8 753.9 627.4 585.9 778.7 769.2 733.5 753.8 848.8
Am. black duck 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
Gadwall 164.9 226.4 127.1 256.4 250.2 414.4 292.7 358.0 414.3 511.7
Am. wigeon 177.3 90.2 110.4 85.5 95.9 123.2 117.9 170.3 198.5 193.2
Am. green-winged teal 106.7 78.7 120.3 162.0 106.0 132.5 131.1 174.4 175.9 152.6
Blue-winged teal 295.3 361.9 596.6 552.9 418.2 521.2 580.2 716.1 526.6 466.6
N. shoveler 321.2 220.7 330.7 165.6 227.9 322.5 294.5 241.4 421.1 421.4
N. pintail 593.4 242.6 447.4 171.4 313.6 317.7 116.3 103.9 372.5 383.4
Subtotal 2461.7 1919.3 2486.4 2021.3 1997.7 2610.3 2301.9 2497.7 2862.8 2977.7
Divers
Redhead 133.9 123.3 143.5 85.7 96.6 162.8 110.8 112.0 110.3 110.3
Canvasback 56.6 59.2 53.5 54.8 36.7 78.1 58.4 32.8 45.9 64.0
Scaups 363.2 322.7 256.2 345.2 158.0 307.3 299.8 288.0 268.4 265.0
Ring-necked duck 18.7 11.7 18.6 35.3 46.5 12.4 14.9 15.4 9.6 12.6
Goldeneyes 16.2 29.9 24.2 31.6 16.1 19.3 10.6 10.1 9.5 15.1
Bufflehead 17.0 33.8 22.7 50.8 32.5 36.5 80.0 67.6 79.6 43.1
Ruddy Duck 43.8 32.9 35.8 77.9 65.6 129.9 193.8 85.2 57.1 65.5
Subtotal 649.4 613.5 554.4 681.3 451.9 746.4 768.3 611.1 580.3 575.5
Miscellaneous
Oldsquaw 0.0 0.0 0.0 0.0 0.0 0.0 0.4 0.0 0.0 0.0
Eiders 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
Scoters 18.6 17.2 1.1 7.2 5.6 9.9 15.5 4.4 0.8 5.2
Mergansers 8.9 8.6 10.1 21.6 8.6 5.0 15.2 8.7 6.3 6.9
Subtotal 27.5 25.8 11.1 28.8 14.2 14.9 31.1 13.1 7.1 12.1
Total Ducks 3138.6 2558.7 3052.0 2731.3 2463.9 3371.6 3101.3 3121.9 3450.1 3565.3
Canada Goose 49.6 79.6 59.0 95.5 79.3 113.8 66.8 100.1 85.1 129.0
Am. coot 327.3 282.2 137.9 166.1 349.5 485.7 279.7 307.4 282.1 234.7
Ponds 828.3 727.5 606.8 417.9 548.9 772.1 695.7 503.2 689.8 720.4
Appendix 1 (continued). Long-term trend in adjusted waterfowl breeding population estimates (thousands) for Southern Alberta.
Species/Ponds 1995 1996 1997 1998 1999 2000 2001
Ducks
Dabblers
Mallard 778.5 793.8 883.6 950.1 1031.8 833.2 743.8
Am. black duck 0.0 0.0 0.0 0.0 0.0 0.0 0.0
Gadwall 410.6 404.2 308.3 360.2 332.5 310.9 256.8
Am. wigeon 179.8 191.1 190.5 150.3 179.6 225.2 186.8
Am. green-winged teal 245.3 314.5 324.4 92.2 190.5 308.1 190.5
Blue-winged teal 430.8 505.9 358.5 521.9 391.5 577.8 367.8
N. shoveler 267.6 373.8 443.2 329.4 408.2 380.4 267.8
N. pintail 198.2 333.5 472.8 166.3 115.0 188.8 66.1
Subtotal 2510.7 2916.8 2981.3 2570.5 2649.2 2824.4 2079.5
Divers
Redhead 95.2 102.7 188.9 67.6 180.7 106.8 54.0
Canvasback 60.5 67.0 68.5 68.6 56.1 73.2 31.9
Scaups 366.5 376.4 347.7 243.1 228.2 292.3 201.9
Ring-necked duck 9.0 10.1 37.4 11.9 52.0 16.2 20.2
Goldeneyes 31.4 6.1 6.9 44.7 5.8 26.5 22.6
Bufflehead 68.3 103.5 91.3 73.9 69.5 70.9 59.2
Ruddy Duck 128.5 302.2 87.1 123.6 73.4 74.3 51.6
Subtotal 759.4 967.8 827.9 633.3 665.8 660.3 441.3
Miscellaneous
Oldsquaw 0.0 0.0 0.0 0.0 0.0 0.0 0.0
Eiders 0.0 0.0 0.0 0.0 0.0 0.0 0.0
Scoters 10.9 0.3 1.3 0.0 0.3 0.0 1.8
Mergansers 10.4 5.9 9.8 5.4 8.1 5.1 8.5
Subtotal 21.3 6.2 11.1 5.4 8.4 5.1 10.3
Total Ducks 3291.4 3890.9 3820.2 3209.2 3323.4 3489.7 2531.1
Canada Goose 158.0 160.2 109.8 191.6 151.8 269.5 213.5
Am. coot 232.9 234.4 377.5 260.0 342.3 418.8 207.4
Ponds 688.7 903.9 1100.4 559.3 716.0 553.1 425.7
Strata 26-29 Mergansers
Population
0
10000
20000
30000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 26-29 Mallard
Population
500000
600000
700000
800000
900000
1000000
1100000
1200000
1300000
1400000
1500000
1600000
1700000
1800000
1900000
2000000
2100000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 26-29 Gadwall
Population
100000
200000
300000
400000
500000
600000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 26-29 American wigeon
Population
0
100000
200000
300000
400000
500000
600000
700000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 26-29 American green-winged teal
Population
0
100000
200000
300000
400000
500000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 26-29 Blue-winged teal
Population
200000
300000
400000
500000
600000
700000
800000
900000
1000000
1100000
1200000
1300000
1400000
1500000
1600000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 26-29 Northern shoveler
Population
100000
200000
300000
400000
500000
600000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 26-29 Northern pintail
Population
0
1000000
2000000
3000000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 26-29 Redhead
Population
0
100000
200000
300000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 26-29 Canvasback
Population
20000
30000
40000
50000
60000
70000
80000
90000
100000
110000
120000
130000
140000
150000
160000
170000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 26-29 Scaups
Population
100000
200000
300000
400000
500000
600000
700000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 26-29 Ring-necked duck
Population
0
10000
20000
30000
40000
50000
60000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 26-29 Goldeneyes
Population
0
10000
20000
30000
40000
50000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 26-29 Bufflehead
Population
10000
20000
30000
40000
50000
60000
70000
80000
90000
100000
110000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 26-29 Scoters
Population
0
10000
20000
30000
40000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 26-29 Ruddy Duck
Population
0
100000
200000
300000
400000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 26-29 Canada Goose
Population
0
100000
200000
300000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 26-29 American coot
Population
0
100000
200000
300000
400000
500000
600000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 26-29 Ponds
Population
400000
500000
600000
700000
800000
900000
1000000
1100000
1200000
1300000
1400000
Year
1960 1970 1980 1990 2000 2010
Strata 26-29 Dabblers
Population
1000000
2000000
3000000
4000000
5000000
6000000
7000000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 26-29 Divers
Population
300000
400000
500000
600000
700000
800000
900000
1000000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 26-29 Miscellaneous
Population
0
10000
20000
30000
40000
50000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 26-29 Total Ducks
Population
2000000
3000000
4000000
5000000
6000000
7000000
8000000
Year
1950 1960 1970 1980 1990 2000 2010
Table 4. Status of waterfowl breeding population estimates (thousands, adjusted for visibility
bias) by species and stratum with comparison against the previous year and the previous long-term
mean for Central Alberta.
Stratum % Change From
Species/Ponds 75 76 2001 Total 2000 Total Long-Term
Mean
2000 Long-Term
Mean
Ducks
Dabblers
Mallard 224.6 278.8 503.3 516.8 419.1 -2.6% 20.1%
Am. black duck 0.0 0.0 0.0 0.0 0.0 -- --
Gadwall 55.2 31.4 86.6 56.9 54.6 52.3% 58.6%
Am. wigeon 39.7 21.8 61.5 44.3 90.4 39.0% -32.0%
Am. green-winged
teal
36.6 34.0 70.7 327.3 118.1 -78.4% -40.2%
Blue-winged teal 55.5 20.6 76.1 246.8 141.2 -69.2% -46.1%
N. shoveler 23.6 77.4 101.0 99.1 81.6 2.0% 23.8%
N. pintail 3.3 2.6 5.9 10.8 20.0 -45.2% -70.4%
Subtotal 438.5 466.7 905.1 1301.9 925.0 -30.5% -2.1%
Divers
Redhead 5.6 14.5 20.1 18.0 33.8 11.6% -40.6%
Canvasback 21.7 3.2 24.9 10.6 35.1 135.1% -29.3%
Scaups 147.0 61.7 208.7 181.0 150.6 15.3% 38.6%
Ring-necked duck 23.8 8.1 32.0 28.5 39.2 12.1% -18.6%
Goldeneyes 43.9 14.7 58.7 35.1 41.0 67.0% 43.2%
Bufflehead 92.3 71.6 163.9 133.9 161.1 22.4% 1.7%
Ruddy Duck 18.4 12.6 31.0 67.8 52.1 -54.2% -40.5%
Subtotal 352.7 186.5 539.2 474.9 513.0 13.5% 5.1%
Miscellaneous
Oldsquaw 0.0 0.0 0.0 0.0 0.0 -- --
Eiders 0.0 0.0 0.0 0.0 0.0 -- --
Scoters 14.5 1.7 16.2 8.8 8.1 84.4% 100.4%
Mergansers 18.2 0.7 18.9 15.5 8.9 21.7% 112.8%
Subtotal 32.7 2.4 35.1 24.3 16.9 44.3% 106.9%
Total Ducks 823.9 655.6 1479.4 1801.1 1454.9 -17.9% 1.7%
Canada Goose 43.8 32.9 76.7 114.5 42.2 -33.0% 81.9%
Am. coot 27.9 21.0 48.9 548.6 146.0 -91.1% -66.5%
Ponds 139.6 266.4 406.0 427.2 480.8 -5.0% -15.6%
Table 5. Long-term trend in adjusted May pond estimates (thousands) by stratum with
comparisons against the previous year and the previous long-term mean for Central Alberta.
Stratum (2001)
Year 75 76 Total
1989 160.4 251.5 411.9
1990 174.4 315.5 489.9
1991 166.1 252.1 418.2
1992 137.2 282.0 419.2
1993 156.2 245.3 401.5
1994 147.2 238.2 385.4
1995 175.1 330.9 505.9
1996 239.3 329.6 569.0
1997 394.1 405.4 799.5
1998 170.5 225.5 395.9
1999 209.0 337.2 546.2
2000 129.0 298.2 427.2
2001 139.6 266.4 406.0
1989-2000 Mean 188.2 292.6 480.8
Percent Change:
From 2000 8.2% -10.6% -5.0%
From 1989-2000 Mean -25.8% -8.9% -15.6%
Appendix 2. Long-term trend in adjusted waterfowl breeding population estimates (thousands) for Central Alberta.
Species/Ponds 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998
Ducks
Dabblers
Mallard 380.2 380.0 369.4 380.9 346.4 384.4 434.0 381.6 431.9 382.8
Am. black duck 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
Gadwall 59.3 62.6 32.1 41.3 31.7 41.1 29.4 64.6 68.3 99.2
Am. wigeon 62.0 84.2 101.6 82.4 97.7 97.2 139.0 115.6 110.8 57.6
Am. green-winged teal 50.6 41.1 57.5 62.7 82.4 121.9 144.0 146.1 167.9 41.4
Blue-winged teal 161.3 160.2 127.2 158.2 55.6 95.1 76.1 163.6 117.0 183.4
N. shoveler 87.4 101.4 60.7 100.6 46.8 65.0 62.6 76.1 113.5 87.4
N. pintail 35.2 23.5 7.2 8.4 2.9 12.5 13.8 18.1 74.4 13.3
Subtotal 835.9 852.9 755.8 834.5 663.4 817.3 899.0 965.8 1083.8 865.0
Divers
Redhead 21.7 26.3 15.0 72.8 31.7 23.1 9.6 18.4 35.7 50.2
Canvasback 28.9 37.6 5.6 13.7 59.0 42.8 10.6 90.4 26.7 61.3
Scaups 128.0 194.9 124.6 153.4 136.9 131.9 126.3 182.5 159.2 81.1
Ring-necked duck 24.7 20.2 18.0 15.5 25.1 88.2 86.2 44.2 26.1 32.2
Goldeneyes 28.5 50.6 39.4 25.2 39.4 55.7 71.0 16.4 73.5 47.0
Bufflehead 87.0 135.2 156.1 220.3 116.7 90.8 136.8 232.2 231.8 202.5
Ruddy Duck 64.7 44.2 5.7 62.8 60.7 4.9 27.5 57.6 7.5 194.8
Subtotal 383.6 509.1 364.4 563.8 469.6 437.4 468.1 641.7 560.6 669.1
Miscellaneous
Oldsquaw 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
Eiders 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
Scoters 9.0 11.4 12.6 10.7 3.4 10.1 11.8 0.5 11.5 4.3
Mergansers 6.6 39.5 2.4 6.0 9.3 3.3 11.3 1.3 0.6 1.3
Subtotal 15.6 50.8 15.0 16.8 12.7 13.4 23.1 1.9 12.1 5.5
Total Ducks 1235.1 1412.8 1135.1 1415.1 1145.7 1268.1 1390.2 1609.4 1656.5 1539.7
Canada Goose 12.5 19.0 15.4 19.8 18.9 20.7 43.3 48.2 29.1 71.1
Am. coot 26.4 158.7 21.6 64.0 62.6 39.7 31.9 37.7 243.3 375.3
Ponds 411.9 489.9 418.2 419.2 401.5 385.4 505.9 569.0 799.5 395.9
Species/Ponds 1999 2000 2001
Ducks
Dabblers
Mallard 640.5 516.8 503.3
Am. black duck 0.0 0.0 0.0
Gadwall 68.6 56.9 86.6
Am. wigeon 93.0 44.3 61.5
Am. green-winged teal 174.0 327.3 70.7
Blue-winged teal 150.1 246.8 76.1
N. shoveler 78.4 99.1 101.0
N. pintail 19.8 10.8 5.9
Subtotal 1224.5 1301.9 905.1
Divers
Redhead 82.9 18.0 20.1
Canvasback 34.5 10.6 24.9
Scaups 207.0 181.0 208.7
Ring-necked duck 61.8 28.5 32.0
Goldeneyes 9.9 35.1 58.7
Bufflehead 190.3 133.9 163.9
Ruddy Duck 27.3 67.8 31.0
Subtotal 613.7 474.9 539.2
Miscellaneous
Oldsquaw 0.0 0.0 0.0
Eiders 0.0 0.0 0.0
Scoters 2.9 8.8 16.2
Mergansers 9.3 15.5 18.9
Subtotal 12.2 24.3 35.1
Total Ducks 1850.4 1801.1 1479.4
Canada Goose 93.8 114.5 76.7
Am. coot 142.4 548.6 48.9
Ponds 546.2 427.2 406.0
Strata 75-76 Mergansers
Population
0
10000
20000
30000
40000
50000
60000
70000
80000
90000
100000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 75-76 Mallard
Population
0
100000
200000
300000
400000
500000
600000
700000
800000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 75-76 Gadwall
Population
0
10000
20000
30000
40000
50000
60000
70000
80000
90000
100000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 75-76 American wigeon
Population
0
100000
200000
300000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 75-76 American green-winged teal
Population
0
100000
200000
300000
400000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 75-76 Blue-winged teal
Population
0
100000
200000
300000
400000
500000
600000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 75-76 Northern shoveler
Population
0
10000
20000
30000
40000
50000
60000
70000
80000
90000
100000
110000
120000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 75-76 Northern pintail
Population
0
100000
200000
300000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 75-76 Redhead
Population
0
10000
20000
30000
40000
50000
60000
70000
80000
90000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 75-76 Canvasback
Population
0
10000
20000
30000
40000
50000
60000
70000
80000
90000
100000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 75-76 Scaups
Population
0
100000
200000
300000
400000
500000
600000
700000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 75-76 Ring-necked duck
Population
0
10000
20000
30000
40000
50000
60000
70000
80000
90000
100000
110000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 75-76 Goldeneyes
Population
0
100000
200000
300000
400000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 75-76 Bufflehead
Population
30000
40000
50000
60000
70000
80000
90000
100000
110000
120000
130000
140000
150000
160000
170000
180000
190000
200000
210000
220000
230000
240000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 75-76 Scoters
Population
0
10000
20000
30000
40000
50000
60000
70000
80000
90000
100000
110000
120000
130000
140000
150000
160000
170000
180000
190000
200000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 75-76 Ruddy Duck
Population
0
10000
20000
30000
40000
50000
60000
70000
80000
90000
100000
110000
120000
130000
140000
150000
160000
170000
180000
190000
200000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 75-76 Canada Goose
Population
0
10000
20000
30000
40000
50000
60000
70000
80000
90000
100000
110000
120000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 75-76 American coot
Population
0
100000
200000
300000
400000
500000
600000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 75-76 Ponds
Population
300000
400000
500000
600000
700000
800000
Year
1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001
Strata 75-76 Dabblers
Population
200000
300000
400000
500000
600000
700000
800000
900000
1000000
1100000
1200000
1300000
1400000
1500000
1600000
1700000
1800000
1900000
2000000
2100000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 75-76 Divers
Population
100000
200000
300000
400000
500000
600000
700000
800000
900000
1000000
1100000
1200000
1300000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 75-76 Miscellaneous
Population
0
100000
200000
300000
Year
1950 1960 1970 1980 1990 2000 2010
Strata 75-76 Total Ducks
Population
0
1000000
2000000
3000000
4000000
Year
1950 1960 1970 1980 1990 2000 2010