We conducted moose surveys in the western Yukon Flats in March and November 2006. The surveys were initiated to estimate early winter moose abundance in the traditional2,269 mi2 moose survey area and to estimate early and late winter moose densities in lands proposed for exchange between the Yukon Flats National Wildlife Refuge (Refuge) and Doyon, Limited (Doyon). The November 2006 population estimate for the traditional 2269 mi2 western Yukon Flats survey area was 418 moose +1- 21% at the 0.90 confidence level; the mean density estimate was 0.18 moose per mi2 +1- 21%, 0.90 confidence leveL We estimated 40% fewer total moose in 2006 compared to 2001 which is a statistically significant decline (P<0.02). The annual rate of decline from 2001 to 2006 is about 8%. Estimated numbers of bulls, cows and calves all follow this declining trend with decreases in 2001, 2005, and 2004 of 18%, 7% and 40%, respectively. The decrease in moose density is likely due to high mortality rates of cow and calf moose as indicated by reported harvest and low numbers of observed calves in moose surveys. Cows comprise a significant portion of moose harvested throughout the Yukon Flats and account for up to 26% of total harvest in the western Yukon Flats. Although bear harvest has significantly increased in the eastern Yukon Flats it has decreased in the western Yukon Flats. Wolf harvest has increased in the western Yukon Flats since 2002. Decreased bear harvest in the western Yukon Flats may be contributing to decreased calf survival. We infer that the moose population in the western Yukon Flats has the capacity to grow quickly based on previous work that documented a high incidence of twinning and good condition of both cow and calf moose. Protection of breeding age cow moose should be the focus for moose management in the Yukon Flats. This objective can be achieved by increased education, outreach and enforcement efforts in partnership with local tribal governments and local residents.