Castro Verde is the main area of cereal steppes in Portugal (ca. 80000 ha), having international importance for several steppe bird species with unfavourable conservation status. In spring 2006, a large-scale census of bird populations in the region was carried out. In the current paper, we (a) update the 2006 population estimates using correction for detectability, (b) report the results of a second census carried out in 2011, (c) explore the likely impacts of the 2005 drought event and land use changes on the observed population trends in the period 2006-2011. Correcting for the detectability bias of the 2006 counts resulted in an increase in population estimates ranging from 6