Four people tented for two days and nights on the wooded slopes of Mount Evermann, the primary peak of Socorro, a volcanic island in the Pacific 400 km southwest of Baja California, Mexico, in April 1981. The island’s endearingly gentle Socorro dove had gone, devoured by Spanish colonists’ cats, forced out by sheep, and shot from the sky by hunters.
The species survived. In 1925, 17 Socorro doves were taken off the island to a California bird keeper. The last Socorro doves on Earth are still alive in confined institutions in Europe and North America approximately 100 years later.
It’s in a peculiar limbo—extinct yet not extinct. Not only the Socorro dove. We found that at least 33 animals and 39 plants live in zoos, aquariums, botanic gardens, and seed banks.
In one sense, this is something that should be celebrated: a tribe that has beaten back the threat of extinction. So what does the future hold for these different kinds of animals? Even with human care, they cannot be preserved permanently. On the other hand, the longer they are kept in captivity, the greater the possibility there is that they will become inbred or that they would lose the genetic variety that helps them defend themselves against illnesses and other dangers. There is always the possibility of complete extinction, particularly if their population sizes are low.
The life of a prisoner
Due to a peculiarity of the red list, conservationists do not regularly measure the number of seeds, plants, or animals that are kept in captivity, nor do they monitor any changes in their condition in the same manner that we do for endangered species that live in the wild. A species that has been extinct in the wild and formerly had thousands of members is indistinguishable from a species that only has a few members left in captivity. We have found a way to overlook the impending extinction of the precise group of animals that is most directly attributable to our actions as a species.
The findings of our investigation into this group have shown some causes for worry. It seems that these populations were initially established by a very small number of people, and it would be necessary to have very large populations—ideally numbering in the thousands—in order to provide the best protection possible against the genetic erosion and extinction that may occur in the future. Sadly, the majority of known species are only kept in very modest numbers (in the hundreds or less), and only a select few institutions house these specimens (fewer than eight in most cases).
Bison native to Europe
Exists there any chance? Maybe unexpectedly so, the answer is yes. In contrast to the eleven species that have been extinct as a result of human activity, twelve have been successfully reintroduced into their natural habitat. Examples include the European bison, which was extinct in the wild as recently as 1927 but is currently prospering in its original area in Russia and Eastern Europe as a result of reintroduction operations that began in the 1950s and utilized stock from European zoos.
The fact that more should follow is encouraging: two-thirds of animals that were once extinct in the wild and just under a quarter of plants that were once extinct in the wild have already been put back into their native habitats. Although it’s possible that these fledgling populations have not yet attained the real “wild” status, as evidenced by, for example, the production of viable young, this is nonetheless an encouraging beginning. They demonstrate that going extinct in the wild does not have to be an inevitable conclusion; rather, it can serve as a springboard for the long-term restoration of a species.
