The azure jay (Cyanocorax caeruleus) (Brazilian Portuguese: Gralha-azul, meaning blue jackdaw) is a passeriform bird of the crow family, Corvidae. It is found in the Atlantic Forest, especially with Araucaria angustifolia, in south-eastern Brazil (São Paulo to Rio Grande do Sul), far eastern Paraguay and far north-eastern Argentina. It is the state bird of Paraná.
The azure jay has a total length of approximately and it weighs about, and is the largest South American corvid. Its plumage is intensely blue with a contrasting black head and upper chest. Males and females are similar, although the females typically are smaller.
Its breeding season is from October to January. This bird is a social breeder. It lays 2–4 eggs and its nest is made of sticks. It is placed above the ground in an Araucaria tree.
It feeds extensively on the nut-like seeds of Araucaria angustifolia, but it is not strictly limited to this, and also feeds on insects and fruit. Like other corvids, azure jays are highly intelligent. Their communication is complex, consisting of at least 14 distinct vocalizations. They form groups of 4 to 15 individuals that are well organized in hierarchies. These groups remain stable for up to two generations.