California Condors are North America's biggest birds, flying or otherwise. They are also one of the world's rarest birds; a Critically Endangered species. The last two wild California Condors were taken out of the wild in 1987 to join the remaining 25 captive individuals in a mass effort to repopulate the species. Conservation organizations, AZA accredited zoos, and public support in all, and two decades later... wild California Condors unabashedly roam Central California's skies again. However, the battle is far from over. The main threat to the sky giants was, and continues to be, lead poisoning. Lead fragments from exploded bullets are found in the carrion they eat, which travels into their blood stream and, if without intervention from biologists, eventually kills them. Biologists are able to track and monitor their health them thanks to GPS devices that are plainly seen attached to their enormous wings.