Summary

Description

Early and late duck production surveys of 125 randomly selected waterbodies and of sections of the Nowitna and Sulatna rivers were conducted on the Nowitna NWR in 1987. Totals of 389and 347 broods were observed during the early and late surveys, respectively. American wigeon broods were the most commonly observed. Northern pintail broods were apparently more abundant than in past years. Overall duck production increased over 1986 on 20 waterbodies surveyed both years, but individual species showed inconsistent changes between years. Average brood sizes for all species changed only slightly from 5year running averages. Mean hatch dates and onset of flight dates were earlier than in past years for most species. Mallard and northern pintail broods were the most commonly observed on the Nowitna and Sulatna rivers. The number of broods observed on the rivers declined substantially from early to late surveys.