The Fernandina Island tortoise, Chelonoidis phantasticus, is a rare reptile native to the Galápagos Islands. This species holds scientific interest due to its unique evolutionary history and its long-standing mystery. Its story highlights the biodiversity of the Galápagos archipelago.
The Rediscovery of a Lost Species
For over a century, the Fernandina Island tortoise was considered extinct, known only from a single male specimen collected in 1906 by the California Academy of Sciences expedition. For decades afterward, only anecdotal evidence, such as droppings and bite marks on cacti, hinted at its continued presence on the remote island. Scientists speculated the species might have succumbed to frequent volcanic activity on Fernandina Island.
In February 2019, an expedition led by the Galápagos National Park Directorate and Galápagos Conservancy discovered a female tortoise on Fernandina Island. This individual, nicknamed “Fernanda” after her island home, was found in an isolated patch of vegetation on the lower, northwestern flank of the volcano. Her discovery provided an opportunity to confirm the species’ persistence.
To verify her species, blood samples were sent to geneticists at Yale University. Researchers compared Fernanda’s DNA with a sample from the 1906 male specimen. In May 2021, genetic tests confirmed Fernanda is Chelonoidis phantasticus, genetically distinct from other Galápagos tortoise species. This re-established the species’ existence.
Unique Characteristics and Volcanic Home
The Fernandina Island tortoise, Chelonoidis phantasticus, is recognized by its saddleback shell. This shell shape, more pronounced in males, features a flared outer edge and saddlebacking at the front. This adaptation allows the tortoise to extend its neck higher, enabling it to reach sparse vegetation in drier, lower elevation environments. Fernanda is estimated to be over 50 years old, but her growth appears stunted, possibly due to limited vegetation in her habitat.
Fernandina Island provides a challenging environment. It is the youngest and third-largest island in the Galápagos, characterized by its active shield volcano, La Cumbre. The island’s landscape is dominated by recent lava flows and a rocky surface, with sparse vegetation. La Cumbre volcano has erupted frequently, with nearly 30 recorded eruptions since 1800, including recent events in 2020 and 2024.
Despite the geologically active landscape, the tortoise survives by adapting its diet. Chelonoidis phantasticus is a terrestrial tortoise, feeding on grasses, herbs, shrubs, and cacti. Constant volcanic activity and lava flows reshape the island, creating isolated patches of vegetation where tortoises seek refuge and sustenance. This species’ ability to persist in such an extreme environment underscores its resilience.
Safeguarding Its Future
The Fernandina Island tortoise is critically endangered, according to the IUCN. Fernanda’s rediscovery prompted conservation efforts aimed at preventing the species from vanishing again. Fernanda currently resides at the Fausto Llerena breeding center on Santa Cruz Island, where she is cared for.
Conservationists from the Galápagos National Park Directorate and Galápagos Conservancy are conducting expeditions to Fernandina Island. The primary goal is to locate additional individuals, especially a male, to establish a breeding program. Signs such as tracks and scat from at least two to three other tortoises have been found, offering hope Fernanda is not the last of her kind.
Searching the rugged, volcanic terrain of Fernandina Island presents challenges due to extensive lava fields and the active volcano. Despite these difficulties, the broader significance of conserving Chelonoidis phantasticus extends beyond this single species. Its survival contributes to the unique biodiversity of the Galápagos ecosystem, which is a living laboratory for evolution. These conservation efforts could provide a model for saving other rare species.