Nestled deep in the open sea around 600 miles off the coast of Ecuador lies the Galapagos Islands, an ecological marvel that has fascinated scientists since the days of Darwin. Though the entire archipelago spans a mere 17,000 square miles of ocean (about half the size of South Carolina), it’s home to nearly 9,000 species of wildlife, many of them endemic to the islands, meaning they’re found nowhere else on Earth.
Take into account that multiple new species are discovered daily around the world and it’s no surprise that scientists are constantly making exciting discoveries in the Galapagos Islands. And sometimes, those discoveries even include species long-presumed extinct among wildlife experts.
Recently, not one but two locally extinct species were discovered to be thriving once again on the islands: the cactus finch and geckos! The reappearance of these species was no coincidence. It came as the result of a painstaking effort among wildlife officials to remove an invasive predator population. In doing so, they made the first steps in restoring and re-wilding the delicate ecosystem of the Galapagos Islands.
Now, when you think “invasive predator,” the massive pythons wreaking havoc on the everglades might spring to mind. Those causing destruction in the Galapagos were a little less terrifying. Rather than man-eating snakes, the culprits behind the devastation were rats.
Numerous Species Flourish on Galapagos Islands Following Rat Removal
Since removing the rats from the islands, scientists have been treated to all sorts of incredible discoveries. First, they found a healthy and growing population of Galapagos Rails (Pachays), an endemic bird never before seen on Pinzón Island. Scientists believe that they migrated from Santiago Island, finding Pinzón the ideal habitat sans rats.
Next, sightings of Cactus Finches soared, a bird species considered extinct on the islands for more than four decades. Then came the most exciting of all: the return of geckos. Unlike their avian neighbors, geckos have never been seen on the islands. The only evidence they ever lived in the area was subfossil records dating back more than 5,000 years. Now, however, the lizards appear to be recolonizing Rábida Island.
“The management measures implemented on these islands in recent decades have been effective. And today, we can see the results,” said Danny Rueda Córdova, director of Galapagos National Park. “The islands have once again become the habitat of endemic species of great importance to the ecosystem. On Pinzón, the Giant Tortoises returned to nest after more than 150 years. Because of our work to remove invasive rodents, the population now reproduces naturally without human intervention.”
Paula Castaño, native species manager at Island Conservation, was similarly amazed by the results of the rat removal. “It is extraordinary to see the change that has taken place on these two islands in the last decade without the presence of rodents,” she said.
“It is inspiring to see how new species establish themselves,” Castaño continued. “And how species that were present, such as the Galapagos Hawks, reproduce successfully and are colonizing new territories and fulfilling their role as top predators, maintaining the balance of the islands’ ecosystem.”