Peregrine falcons have made a remarkable recovery from near-extinction following pesticide bans. Urban peregrines now nest on cathedrals and skyscrapers, but still face illegal persecution in some areas.
Peregrine recovery represents one of conservation biology's great welfare and population successes. But illegal persecution continues, with nests disturbed, eggs destroyed, and birds shot or poisoned on some grouse moors. Each persecution incident represents both a criminal act and a welfare failure. The ease with which this species recovers when protected demonstrates the power of effective wildlife law enforcement.