Cyanocorax caeruleus is rare to locally common in south-east Brazil (south São Paulo south to Rio Grande do Sul), north-east Argentina (Misiones and north Corrientes). A small number of records exist for Paraguay^1,2,5,7, but these are not considered credible⁹. Populations have apparently declined substantially, particularly in the west of its range, and is now most common in south-east Brazil⁷.