Date of this Version
Published in Administrative Report (2006) 24 pages.
This report summarizes information about the status of duck populations and wetland habitats during spring 2006, focusing on areas encompassed by the U.S. Fish and Wildlife (USFWS) and Canadian Wildlife Services’ (CWS) Waterfowl Breeding Population and Habitat Survey. This report does 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. 1), 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 36.2 ± 0.6 [SE] million birds. This was 14% greater than last year’s estimate of 31.7 ± 0.6 million birds and 9% above the 1955-2005 long-term averagea (Tables 1-12; Appendix A). Mallard (Anas platyrhynchos) abundance was 7.3 ± 0.2 million birds, which was similar to last year’s estimate of 6.8 ± 0.3 million birds and the long-term average. Blue-winged teal (A. discors) abundance was 5.9 ± 0.3 million birds. This value was 28% greater than last year’s estimate of 4.6 ± 0.2 million birds and 30% above the long-term average. The estimated abundance of green-winged teal (A. crecca; 2.6 ± 0.2 million) was 20% greater than last year and 39% above the long-term average. The estimated number of gadwall (A. strepera; 2.8 ± 0.2 million) was 30% greater than last year and was 67% above the long-term average, whereas the estimated number of redheads (Aythya americana; 0.9 ± 0.1 million) increased 55% over 2005 and was 47% above the long-term average. The abundance of canvasbacks (A. valisineria; 0.7 ± 0.1 million) increased 33% over last year and was 23% over the long-term average. Northern shovelers (Anas clypeata; 3.7 ± 0.2 million) were 69% above their long-term average. Although the abundances of most species increased over last year and were greater than their long-term averages, American wigeon (A. americana; 2.2 ± 0.1 million) and scaup (Aythya affinis and A. marila combined; 3.2 ± 0.2 million) were 17% and 37% below their long-term averages, respectively. The estimate for scaup was a record low for the second consecutive year. The abundance of northern pintails (Anas acuta; 3.4 ± 0.2 million) was 18% below the 1955-2005 average, although this year’s estimate was 32% greater than that of last year.