Trends in Duck Breeding Populations 1955-2011

• Main Authors: Zimpfer, Nathan L., Rhodes, Walter E., Silverman, Emily D., Zimmerman, Guthrie S., Richkus, Ken D.
• Format: Text
• Language: unknown
• Published: DigitalCommons@University of Nebraska - Lincoln 2011
• Subjects: Northern Shoveler; Polysticta stelleri; Shoveler
• Online Access: https://digitalcommons.unl.edu/usfwspubs/289; https://digitalcommons.unl.edu/context/usfwspubs/article/1288/viewcontent/2011Trends_in_Breeding_Duck_Populations.pdf

Services' (CWS) Waterfowl Breeding Population and Habitat Survey. We do not include information from surveys conducted by state or provincial agencies. In the traditional survey area, which includes strata 1-18, 20-50, and 75-77 (Figure 1), the total duck population estimate (excluding scoters [Melanitta spp.], eiders [Somateria spp. and Polysticta stelleri ], long- tailed ducks [Clangula hyemalis], mergansers [Mergus spp. and Lophodytes cucullatus], and wood ducks [Aix sponsa]) was 45.6 ± 0.8 [SE] million birds. This represents an 11% increase over last year's estimate of 40.9 ± 0.7 million, and is 35% higher than the long-term averagea (1955-2010; Table 1). 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 (Table 2). 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; Table 3). 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 (Table 4). 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 (Table 5). The estimate of blue-winged teal abundance (A. discors) was 8.9 ± 0.4 million, which was 41% and 91% above the 2010 estimate and the long-term average, respectively (Table 6). 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 (Table 7). 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 (Table 8). Redhead abundance (Aythya americana; 1.4 ± 0.1 million) was 27% above the 2010 estimate and 106% above the long-term average (Table 9). The canvasback estimate (A. valisineria; 0.7 ± 0.05 million) was ...