Searching for a Needle in the Haystack: Re-Discovery of Endangered Species
Tracking down presumed-extinct species is no easy task. This endeavor is sometimes akin to searching for a needle in a haystack. In the midst of the biodiversity crisis we face during this period known as the Anthropocene, or the Age of Humans, often referred to as the Sixth Extinction, the rediscovery of lost species is causing significant excitement within the scientific community.
“The rediscovery of long-lost species amidst the challenges of habitat degradation and human-induced threats, highlights the urgent need for conservation efforts in the face of the ongoing biodiversity crisis.”
Considering each species as a unique book in the library of biodiversity, feeling excitement is entirely justified. When Pierre Mvogo Ndongo went to Sierra Leone in January 2021 to search for “lost” species of land crabs, he intimately experienced the sensation of searching for a needle in a haystack. The vastness of the geographic area considered a ‘haystack’ was the reason for this. The only clue for the Afzelius crab (Afrithelphusa afzelii), last seen in 1796, was a tag on a specimen that read “Sierra Leone.” For about two centuries, this species had been considered lost, raising questions: Could it be found again? Or was it still alive? These were significant inquiries, but given that it had never entered any scientific record lists until now, this species likely had, in all probability, become extinct.
These crabs, known as unique members of an Afro-tropical family, were typically vibrant species found in rainforests, often away from permanent water sources. They could climb trees, inhabit rock crevices, dig into swamps, or create burrows on the forest floor. The five known species in Africa were living in Sierra Leone, Guinea, and Liberia. Afrithelphusa afzeliihad not been seen for a staggering 225 years, and the only information on where to search for it was the geographical location indicated by the tag, which simply read ‘Sierra Leone.’ This was indeed a rather nonspecific geographic description, as it encompassed a large geographic area.
Researchers concluded that the specimen must have been collected within walking distance of Freetown, leading them to initiate their search in the surrounding forest. However, this was still a very vague search step. The research team inquired with the local community about the presence of any land crabs away from rivers and streams until they encountered someone who could assist. According to one of the responses, they were quite fortunate. A local person they met led the research team to his farm at the edge of the forest, where, after intensive searches, the species was rediscovered. In addition to the rediscovered Afzelius crab, two new freshwater crab species were also found through this process.
The habitats of these crabs are under threat due to the destruction of forests for agriculture and fuelwood. Deforestation is one of the most significant factors triggering the biodiversity crisis. The population size of this crab species must have significantly dwindled, considering it hasn’t appeared on any species list for 225 years, remaining in a lost status.
“In the midst of the Anthropocene, the rediscovery of presumed-extinct species evokes significant excitement within the scientific community, emphasizing the critical impact of human activities on global biodiversity.”
A similar situation unfolded recently for a lost bird species. The black-naped pheasent piegon(Otidiphaps insularis) was captured on camera in Papua New Guinea, 140 years after its last sighting. This species, not heard from for over a century, was considered among the extinct bird species. However, after a month of searching, the observation team in the field captured images of the species in the depths of a forest on a small island off Papua New Guinea in September. According to BBC, John Mittermeier, one of the leaders of the discovery expedition, described it as feeling like finding a “unicorn.” Researchers hope that this discovery will contribute to preventing the extinction of the species.
We are in a time when the biodiversity crisis is keenly felt. The loss of species that have navigated the challenging paths of evolutionary history to reach the present, all due to human impact, represents a significant cost to global biodiversity. Therefore, discoveries like these excite ornithologists and especially scientists dedicated to biodiversity. Some team members had previously attempted to find this large ground dove. In 2019, a few members searched Fergusson Island, the species’ sole habitat, but found no trace of the bird. The team expanded their fieldwork until 2022, reaching villages on the western slope of Mount Kilkerran, the island’s highest peak. Jason Gregg, a conservation biologist and leader of the discovery team, noted, “[There], we began meeting hunters who had seen and heard the black-eared ground dove.” A local individual, in particular, provided a promising lead, having spotted the dove several times in a rugged area with slopes and valleys and even heard its distinctive call.
Researchers set up camera traps in the area, and eventually, a few days before the team left the island, they captured images of the bird. Jordan Boersma, a researcher from Cornell University, mentioned, “Browsing through the photos, the image of this bird passing right by our camera stunned me.” The captured images represent the first documented example of the long-lost bird since 1882, the year Charles Darwin passed away.
Discoveries like these are the moments ornithologists, biogeographers, and conservation biologists have always dreamed of. Very little is known about this species — a creature that has been absent for nearly 150 years. Researchers believe the population size of the species is represented by very low numbers. However, the team hopes that the information they have gathered can be used to aid in the conservation of the remaining birds. Similar to the African crab species found two centuries later, this species is also threatened due to habitat degradation from deforestation and agricultural activities. The population decline is attributed to tree felling. Undoubtedly, habitat loss poses a significant threat to this species, leaving it with nowhere to escape, just like the African crab species found after two centuries.
One of today’s most significant threats to natural life is the loss of forests due to the increasing human population. Let me emphasize this once again at the end of the text because species facing such threats lack the capacity to combat them, and the irreversible harm caused by losing each species impacts the world heritage of biodiversity, which amounts to 3.8 billion years.