studies on the avian assemblage that inhabits the araucaria araucana forests are scarce. as a result, the seasonal changes of the assemblage, the effects of snow cover on bird diversity during winter, and the importance of forest structural components for birds are barely known. between 2008 and 2009, we undertook studies of the bird assemblage in these forests in the araucanía district, southern chile. by means of point counts and call surveys, we registered a total of 29 species. we found marked seasonal changes in the assemblage. both bird richness and relative abundance were maximum in summer and minimum in winter. snow depth was negatively related with species richness and bird relative abundance during winter. understory birds (e.g., scelorchilus rubecula, scytalopus magellanicus) were absent when snow was deeper than 1 m. large-tree users (e.g. colaptes pitius, campephilus magellanicus) were not affected by snow depth. bird richness was best predicted by the diameter at breast height of trees through a positive relationship. a. araucana forests provide habitat with a structural complexity that benefits avian diversity and they are important for bird conservation. this is particularly relevant for bird guilds with specific habitat requirements (understory users and large-tree users), which have been the most affected birds by centuries of exploitation of the temperate forests in southern south-america.