Moose population status, trends in productivity, survival and abundance monitored by aerial surveys and other means in four Alaskan study areas during 1950-1972 are reviewed. Moose numbers were high or increasing from 1950 to 1960 in all areas studied due to extensive and repeated wildfire in the 1940s and 1950s, moderate snow severity in the 1950s, predator control in the 1950s, and the restriction of hunting to bulls only prior to 1966. During the 1960s, several winters of severe snow conditions precipitated moderate to high winter moose mortality, mainly in response to varying depth and duration of snow cove, but modified by moose population levels and habitat condition. Mortality primarily affected calves and secondarily affected old moose. Males appeared more susceptible than females. In the most severe cases all age classes were affected, and losses equaled 50 percent or more. Aerial sex and age composition survey data reflected major changes in population structure resulting from winter mortality and from selective mortality such as hunting of bulls. Population composition during recovery following extensive winter mortality was not consistent among study areas, and varied in response to the particular combination of ecological factor prevailing at the time. In one area (Nelchina Basin) a high wolf population probably played a major role in retarding growth of a reduced moose population. Annual increments of 25 to 30 percent occurred during periods favorable to population increase and in areas with mild winters, few predators, and invasive hunting, but did not persist under less favorable circumstances. The potentially great variation in moose production and survival in areas where population and habitat manipulation are minimal should be recognized in formulating management programs.