Species extinct in the wild in limbo

PARIS — For species classified as “extinct in the wild,” the zoos and botanical gardens whose fate hangs in the balance are often gateways to oblivion as gateways to recovery, new research has shown.

The reintroduction of often single-digit populations faces the same challenges that brought these species to the brink of extinction in the first place, including a lack of genetic diversity. But without conservation efforts, experts say, these species’ chances of survival would be even smaller.

According to the results, nearly 100 species of animals and plants that have been wiped out from the wild by hunting, pollution, deforestation, invasive life forms and other causes of extinction have received critical attention from scientists and conservationists since 1950.

Although the “extinct in the wild” category was not added to the authoritative Red List of Threatened Species until 1994, the term could have applied to all.

Of these marginally teetering species, 12 have been reintroduced to some degree in the wild, according to two studies published in the journals Science and Diversity last week.

Other 11, however, have gone the way of dinos, dodos, and dozens of Pacific island trees whose delicate blossoms will never again grace the planet.

Biodiversity loss has reached critical proportions not seen since the impact of a stray asteroid the size of Paris 66 million years ago, wiping out land dinosaurs and ending the Cretaceous Period.

That was one of five so-called mass extinctions in the last half billion years.

Scientists say human activities have propelled the Earth into the sixth, with species disappearing 100 to 1,000 times faster than normal.

“There are many real opportunities to prevent extinctions and return previously lost species to the wild, and we must seize them,” said the international team of 15 authors.

“We have lost 11 species entirely under our care to extinction since 1950.”

– Success Stories –

Another study published in Current Biology last week, looking at the “Great Dying Out” 252 million years ago that wiped out 95 percent of life on Earth, showed that accelerated species loss preceded a broader ecological collapse.

“Currently, we may be losing species faster than in any previous Earth extinction event,” lead author Yuangeng Huang, a researcher at China University of Geosciences, told AFP.

“We cannot predict the tipping point that will send ecosystems into total collapse, but it is an inevitable outcome if we don’t reverse biodiversity loss.”

Recent conservation success stories – some heroic – include the European bison that once roamed Europe.

By the 1920s, their numbers had been reduced so much that surviving specimens were herded to zoos and a breeding program started in Poland.

After being reintroduced in 1952, the broad-shouldered animals thrived and are no longer considered critically endangered by the International Union for the Conservation of Nature (IUCN), the custodians of the Red List.

Red wolves in North America, wild horses in Central Asia, and the desert-dwelling Arabian oryx have all made comebacks with the help of human hands.

So does the world’s largest tortoise, which is native to the Galapagos island of Espanola.

By the 1970s, Chelonoidis hoodensis was eaten to the brim. Fourteen surviving individuals were removed and decades later relocated to another island, where their numbers are increasing.

– ‘Overlooked Category’ –

Pinta giant tortoises on a neighboring Galapagos island — one of 11 species extinct in the wild that didn’t make it — weren’t so lucky.

After living for half a century as the only survivor of his species, a 75-kilogram man named Lonesome George died in 2012.

Other creatures that never made it out of the ICU include Hawaii’s black-faced honeycreeper, a dainty bird devastated by mosquito-borne avian malaria, last seen in 2004; Mexico’s freshwater pupfish Catarina, which was unsuccessfully relocated in captivity when its original habitat dried up due to groundwater abstraction; and five species of snails in the Society Islands, which fell prey to an invasive carnivorous cousin.

Surprisingly, the studies show that species that survive only in controlled environments are in a kind of conservation limbo.

“This is an overlooked category,” the researchers noted.

“Although they are listed as most endangered, extinct species in the wild are not assessed as part of the Red List process.”

“We have largely ignored the magnitude and variability of the risk of extinction in the very species group for which humans are most responsible,” they added.

Of the 84 species that currently have this status, almost half have not benefited from attempts to reintroduce them into the wild. Most are plants, suggesting a possible propensity for animal reintroduction that may not be fully scientifically justified.

At its last World Conservation Congress in 2020, the IUCN called for the reintroduction of extinct species into the wild by 2030.