2011 Population Estimates

Total Breeding Duck Population Estimates

Total Breeding Duck Population Estimates

In the traditional survey area, which includes strata 1-18, 20-50, and 75-77, the total duck population estimate (excluding scoters [Melanitta spp.], eiders [Somateria spp. and Polysticta elleri], long- tailed ducks [Clangula hyemalis], mergansers [Mergus spp. and Lophodytes cucullatus], and wood ducks [Aix sponsa]) was 45.6 million birds. This represents an 11% increase over last year's estimate of 40.9 million, and is 35% higher than the long-term average.

Mallard Population Estimates

Mallard Population Estimates

The estimated mallard (Anas platyrhynchos) abundance was 9.2 ± 0.3 million, which was 9% above the 2010 estimate of 8.4 ± 0.3 million, and 22% above the long-term average of 7.5 ± 0.04 million.

Northern Pintail Population Estimates

Northern Pintail Population Estimates

The estimate for northern pintails (A. acuta; 4.4 ± 0.3 million) was 26% above the 2010 estimate of 3.5 ± 0.2 million and similar to the long-term average.

Blue-winged Teal Population Estimates

Blue-winged Teal Population Estimates

The estimate of blue-winged teal abundance (A. discors) was 8.9 ± 0.4 million, which was 41% and 91% above the 2011 estimate and the long-term average, respectively.

Green-winged Teal Population Estimates

Green-winged Teal Population Estimates

The estimated abundance of green-winged teal (A. crecca) was 2.9 ± 0.2 million, which was 17% below the 2010 estimate and 47% above the long-term average.

American Wigeon Population Estimates

American Wigeon Population Estimates

The estimate for American wigeon (A. americana; 2.1 ± 0:1 million) was 14% below the 2010 estimate and 20% below the long-term average.

Gadwall Population Estimates

Gadwall Population Estimates

Estimated abundance of gadwall (A. strepera; 3.3 ± 0.2 million) was similar to the 2010 estimate and 80% above the long-term average (1.8 ± 0.02 million).

Scaup Population Estimates

Scaup Population Estimates

Estimated abundance of scaup (A. affinis and A. marila combined; 4.3 ± 0.3 million) was similar to that of 2010 and 15% below the long-term average of 5.1 ± 0.05 million.

Northern Shoveler Population Estimates

Northern Shoveler Population Estimates

The northern shoveler (A. clypeata) estimate was 4.6 ± 0.2 million which was 14% above the 2010 estimate and 98% above the long-term average.

Redhead Population Estimates

Redhead Population Estimates

Redhead abundance (Aythya americana; 1.4 ± 0.1 million) was 27% above the 2010 estimate and 106% above the long-term average.

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