Between July 17 and 24, 1989, duck brood surveys were conducted on the Pah River Flats, in interior Alaska, and McCarthy's Marsh, on the Seward Peninsula. Ten plots, 26 square kilometers (km2) in size, on the Pah Flats and 13 plots on the Seward were surveyed, yielding duck production estimates of 212 and 5.22 young/km respectively. Observed production differed significantly (P < .0005) between the two habitats, and is presumed to be low in 1989 due to weather influences. Species composition of adults also differed markedly between the two habitats. It is difficult to obtain precise estimates of variable populations from small-scale surveys and in remote areas. Methods to reduce the variance of estimates of waterfowl brood density include stratification, use of the finite population correction factor in computations, and ratio estimation using an auxiliary variable (number of-waterbodies).
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