The Lords of Prey (also known as the "Birds of Prey") were an evil race of raptors that lived in the mountain clefts of Natalia, such as the High Bleaks. They preyed upon rabbits, and thus both races held each other as mortal enemies. The various members of the Lords of Prey include Hawks, Eagles, Owls, and Falcons.
The rabbits of Natalia first discovered the Birds of Prey when Fleck Blackstar and an explorers' expedition led across Ayman Lake from Seddleton came upon the future site of the settlement of Kingston; there, they were attacked by the Birds of Prey and were thus forced to flee across the Lake. Their flight was unsuccessful, however, and upon the waters of Ayman they fought the Battle of Ayman Lake, which the rabbits won in the end.
Over the centuries, the Birds were a constant menace to rabbit civilization, although by the time of the reign of King Jupiter, they were largely subdued.
By the events of The Green Ember, King Jupiter had been slain by Morbin Blackhawk, the leader of the Birds, and the kingdom of the Thirty Warrens had fallen into decay, once more at the mercy of the winged menace of the mountains.