US Fish & Wildlife Service
Date of this Version
2004
Citation
Published in Administrative Report (2004) 19 pages.
Abstract
This report summarizes information about the status of duck populations and wetland habitats during spring 2004, focusing on areas encompassed by the U.S. Fish and Wildlife and Canadian Wildlife Services’ Waterfowl Breeding Population and Habitat Survey. The estimates 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 (Fig. 2), the total duck population estimate (excluding scoters [Melanitta spp.], eiders [Somateria and Polysticta spp.], long-tailed ducks [Clangula hyemalis], mergansers [Mergus and Lophodytes spp.], and wood ducks [Aix sponsa]) was 32.2 ± 0.6 [SE] million birds, 11% below (P < 0.001) last year’s estimate of 36.2 ± 0.7 million birds and 3% below the 1955-2003 long-term average (P = 0.053). Mallard (Anas platyrhynchos) abundance was 7.4 ± 0.3 million birds, which was similar to last year’s estimate of 7.9 ± 0.3 million birds (P = 0.177) and the long-term average (P = 0.762). Blue-winged teal (A. discors) abundance was 4.1 ± 0.2 million birds. This value was 26% below last year’s estimate of 5.5 ± 0.3 million birds (P < 0.001) and 10% below the long-term average (P = 0.073). Of the other duck species, only estimates of northern shovelers (A. clypeata; 2.8 ± 0.2 million) and American wigeon (A. americana; 2.0 ± 0.1 million) were significantly different from 2003 estimates (P < 0.003), and both were 22% below 2003 estimates. Compared to the long-term averages, gadwall (A. strepera; 2.6 ± 0.2 million; +56%), green-winged teal (A. crecca; 2.5 ± 0.1 million; +33%) and shovelers (+32%) were above their 1955-2003 averages (P < 0.001), as they were in 2003. In 2004, northern pintails (A. acuta; 2.2 ± 0.2 million; -48%) and scaup (Aythya affinis and A. marila combined; 3.8 ± 0.2 million; -27%) remained well below their long-term averages (P < 0.001). Wigeon also were below their long-term average in 2004 (-25%; P < 0.001). Estimates of redheads (A. americana) and canvasbacks (A. valisineria) were unchanged from their previous year and long-term averages (P ≥ 0.396).