"It was April in 1981 when a party of four camped for two days and nights on
the forested slopes of Mount Evermann, the central peak of Socorro, a volcanic
island in the Pacific some 400 kilometres southwest of Baja California, Mexico.
Their fruitless search confirmed their suspicions: the Socorro dove, an
endearingly tame bird unique to the island, had disappeared, eaten by the cats
of Spanish colonists, pushed out by grazing sheep and shot from the sky by
But the species had not vanished. Fifty six years prior to this search, in
1925, 17 Socorro doves had been collected from the island and transported to a
bird keeper in California in the US. Somehow, almost 100 years later, the
descendants of these birds – the last Socorro doves on the planet – are still
with us, distributed across captive facilities in Europe and North America.
It’s a strange liminal space: disappeared from the wild, yet not entirely
extinct. And it’s one not peculiar to the Socorro dove. Our research has
confirmed that at least 33 animals and 39 plants no longer have wild
populations, but survive under human care in places such as zoos, aquariums,
botanic gardens and seed banks.
These species are categorised as “extinct in the wild” under the IUCN Red List
of Threatened Species, the system conservation biologists use to evaluate and
communicate extinction risk. It’s a diverse set that includes the manicillo, a
relative of the peanut only found in Bolivia; the Tali palm originally
identified from a lone specimen on the campus of Dhaka University in
Bangladesh; and a number of tree snails from the remote Society Islands in the
In one sense, here is something worth celebrating: a group that has given
extinction the slip. But what does the future look like for these species?
Human care will not preserve them indefinitely. On the contrary, the longer
they spend in captivity the more they risk becoming inbred or losing the
genetic diversity that helps them resist diseases and other threats.
Eventually, outright extinction looms, especially if their populations are
*** Xanni ***
Chief Scientist, Xanadu
Partner, Glass Wings
Manager, Serious Cybernetics