Extinction represents the permanent loss of a species from the planet, a final verdict in the history of life. However, certain animals have challenged this finality, reappearing in the wild after being absent for decades, centuries, or even millennia. The compelling stories of these resurrected species offer a rare sense of hope and demonstrate the remarkable tenacity of nature when faced with ecological collapse. These reappearances highlight the imperfections in scientific observation and significantly shift conservation priorities.
Defining Extinction and the Lazarus Phenomenon
The International Union for Conservation of Nature (IUCN) provides the global standard for classifying a species as Extinct (EX). This classification is assigned only when there is no reasonable doubt that the last individual has died, based on exhaustive surveys throughout its known and expected habitat. A separate category, Extinct in the Wild (EW), applies to species that survive only in captivity or as populations outside their historical range. The reappearance of a species that was declared Extinct is known in biology as the “Lazarus phenomenon.” The term Lazarus species refers to an organism that reappears after a long period of absence, often due to incomplete sampling or the creature surviving in an isolated, unstudied location.
Species Rediscovered (The Hidden Survivors)
The most dramatic examples of species returning from presumed extinction are those that were simply found again, having maintained a secret existence unknown to researchers. These rediscoveries are typically attributed to the species inhabiting remote, specialized, or deep-sea environments where human observation is limited.
Coelacanth
The Coelacanth is perhaps the most famous example. This lobe-finned fish was known only from fossils dating back 409 to 66 million years, and scientists believed it had vanished entirely during the Cretaceous period. This assumption was shattered in December 1938 when a specimen was caught off the coast of South Africa near the Chalumna River. The fish was identified by museum curator Marjorie Courtenay-Latimer. It was later determined that this deep-dwelling species, Latimeria chalumnae, lived in caves at depths between 90 and 300 meters. A second species, Latimeria menadoensis, was discovered in Indonesian waters in 1997, confirming the genus’s hidden survival.
Lord Howe Island Stick Insect
Another remarkable case is the Lord Howe Island Stick Insect, often called the “tree lobster,” which was considered extinct by 1920. The species disappeared from its native Lord Howe Island after the introduction of black rats following a shipwreck in 1918. In 2001, a tiny population was rediscovered on Ball’s Pyramid, a sheer, uninhabited volcanic sea stack located 23 kilometers away. The entire surviving population, estimated to be only 24 individuals, was found clinging to a single, isolated shrub on the rocky outcrop. This minuscule, hidden refuge preserved the species until scientists began a captive breeding program with just two pairs of the rare insects.
Bermuda Petrel
A historical avian example is the Bermuda Petrel, or Cahow, which was thought to be extinct for over 300 years. The nocturnal seabird vanished from the main islands of Bermuda after the arrival of human settlers and the introduction of non-native predators like rats and pigs. Its eerie cries were once so unsettling to Spanish sailors that they believed the islands were haunted. In 1951, a small colony of the petrels was rediscovered on a few tiny, rocky islets in Castle Harbour. The initial finding consisted of only 18 nesting pairs, a precarious foundation for the species’ future.
Species Recovered (Through Conservation Intervention)
Some species that were functionally extinct in the wild were saved only by intensive conservation strategies involving human intervention. These animals were actively rescued from the brink of total collapse rather than simply rediscovered.
California Condor
The California Condor, one of North America’s largest flying birds, reached this grim state by the mid-1980s due to habitat loss and lead poisoning from scavenged carcasses. By 1982, only 22 individuals remained in the wild, prompting the controversial decision to capture all remaining condors by 1987 to start a captive breeding program. To accelerate reproduction, which is naturally slow as the birds typically lay only one egg every other year, scientists used a technique called double-clutching. This involves removing the first egg to encourage the female to lay a second egg, effectively doubling the annual production. The population slowly grew in captivity, allowing reintroduction efforts to begin in 1992, successfully establishing free-flying populations in California and Arizona.
Black-footed Ferret
The Black-footed Ferret, a small, nocturnal predator native to the Great Plains, was considered extinct twice in the 20th century. Its population plummeted due to the deliberate extermination of its primary prey, the prairie dog, and the introduction of sylvatic plague. A small, isolated population was rediscovered in Wyoming in 1981, but disease reduced the number to only 18 individuals by 1986. These 18 ferrets became the foundation of a nationwide captive breeding and reintroduction program. The ferrets are now released into the wild at various sites across the western United States, but their recovery is a constant effort. Recently, genetic diversity, which was extremely low due to the small number of founders, has been boosted through conservation cloning, adding a unique genetic line to the captive stock.
Arabian Oryx
The Arabian Oryx represents a global success story in reversing the status of a species declared Extinct in the Wild (EW). The white antelope was hunted to extinction in its native Arabian Peninsula by 1972. Conservationists launched “Operation Oryx” in the 1960s, capturing the last few wild individuals to establish a “World Herd” in zoos and private collections. The goal was always reintroduction, and the first major release occurred in Oman in 1982. Through sustained captive breeding, habitat protection, and reintroduction across several Middle Eastern countries, wild populations were successfully re-established. In 2011, the Arabian Oryx became the first mammal to be downgraded by the IUCN from Extinct in the Wild to Vulnerable.