Anne Pusey

In January 1979 Craig Packer with colleague and wife Anne Pusey, began their study of lions in Nogorongoro Crater, a 2,000-foot-deep caldera with a hundred square mile floor located at the eastern edge of Tanzania's Serengeti Plain. The craters's cliff walls serve to isolate about 100 lions from their nearby Serengeti counterparts.

Suspecting the lions were subjected to repeated inbreeding and that they may conceal genetic vulnerabilities, the Packers set about reconstructing the family tree of at least five generations of every lion that lived in the crater. The scientific mystery would take ten years to solve.

The method used by the Packers incorporated the monumental task of assembling and organizing all the lion photographs they could find from around the world, from biologists and scientists who had studied the crater lions, through to film crews and tourists who had journeyed to the crater floor since the road granting access was completed in 1959.

In 1979 Packer and Pusey began using lion ID cards with pictures of individuals at various ages, noting field marks such as whisker spots and ear notches to pinpoint lions. They contacted preceding researchers who had photographed or drawn the same lions or their forebears and solicitied photographs taken by tourists, receiving hundreds to help fill in the gaps.

Eventually their catalog put faces on more than 500 individuals, most now dead. Their detective work determined that all of today's crater lions descend from only 15 lions that either survived the flies or invaded Ngorongoro shortly thereafter.

This photo chronology revealed that the entire crater population descended from 15 animals. Only eight individuals survived the plague while the others were males that may have entered the crater from the Serengeti. The plague had removed so many adult males from the crater that fresh blood was able to enter. Once the residents resumed breeding, they had several large sets of sons that monopolized the crater prides and kept any additional immigrant males out. Thus the current crater population has been subject to close inbreeding since 1969, about five lion generations.

Much of what is known about the life of lions in the wild has come from long term studies of them in the Serengeti National Park in Tanzania. Starting in 1966, George Schaller, then I [Brian Bertram], then David Bygott and Jeanette Hanby, and then Craig Packer and Anne Pusey, and several associates, have been able to keep tabs on the fortunes of individually recognized lions and their prides for over 30 years. There have been few other studies of individual wild animals that have been going so long, or that have yielded so much information,