A rookery is a colony of breeding animals, generally birds. A rook is a Northern European and Central Asian member of the crow family, which nest in prominent colonies (multiple nests) at the tops of trees. The term is applied to the nesting place of birds, such as crows and rooks, the source of the term. The breeding grounds of colony-forming seabirds and marine mammals (true seals or sea lions) and even some turtles are also referred to as rookeries.
The term rookery was also borrowed as a name for dense slum housing in nineteenth-century cities, and especially London.
Paleological evidence points to the existence of a pterodaustro rookery.