 Appalled at the depredations visited by feral pigs upon the island's brown booby and masked booby colonies (reduced to 500 and 150 birds, respectively), Stager procured a shotgun and killed all 58 pigs.By 2003, the booby colonies had 25,000 brown boobies and 112,000 masked boobies, the world's second-largest brown booby colony and its largest masked booby colony.When the independence of Algeria in 1962 threatened French nuclear testing sites in Algeria, the French Ministry of Defense considered Clipperton Island as a possible replacement.