A nearly extinct Caribbean reptile is showing signs of a comeback after years of conservation efforts. The population of the Sombrero ground lizard (Pholidoscelis corvinus) has increased from fewer than 100 individuals in 2018 to over 1,600 in 2024. The enormous population jump is detailed in a survey published on December 18.
A Sombrero ground lizard (Pholidoscelis corvinus) filmed in 2023. CREDIT: © Justin Springer / Rewild.
Sombrero ground lizards are a small reptile that primarily eats the eggs of ground-nesting birds, corn, and other plants. It is endemic to Sombrero, the northernmost island of the Lesser Antilles and about 55 miles off the coast of Anguilla. This small Caribbean island is in the top three of the world’s 36 biodiversity hotspots, with several species doing so too only found on this 94 hectare island. The colorful Sombrero Island bee, a future pygmy gecko, the Sombrero Island wind scorpion, and countless others all call this place home. The island is also home to large seabird colonies and has been designated an Important Bird Area.
“The Critically Endangered Sombrero Ground Lizard is an endemic species, meaning it is only found on Sombrero Island and nowhere else in the world,” Farah Mukhidasays a natural resources manager and executive director at Anguilla National Trust Popular science. “It is a beautiful little reptile with its black-blue scales.”
A study from 1999 it was estimated that only between 396 and 461 individuals remained. Sombrero Island was also once on the brink of environmental collapse. Mining, a population of invasive mice, deforestation and major hurricanes had all taken their toll.
“That it has managed to survive decades of phosphate mining, invasive species and now climate change, with longer periods of drought, higher temperatures and even stronger hurricanes and storm surges sweeping across the island, is absolutely astonishing and shows just how resilient this lizard is. ,” says Mukhida.
Important conservation efforts will begin in 2021 have focused on removing the invasive mice and planting more native species on the island. Experts from the Anguilla National Trust, Fauna & Flora and Re:wild have been working to help restore the Sombrero ground lizard and its island habitat. The lizards are showing tremendous signs of improvement, with their population increasing by about 16 times in six years.
“We were absolutely ecstatic when we analyzed the results of our population surveys and discovered this huge increase in their numbers,” says Mukhida.
The island itself has been declared pest-free and is much greener. Native plants, including the sea bean, sea grape and prickly pear, are already showing healthy new growth. Conservationists also express some cautious optimism for the future.
“This is a remarkable turnaround for this bold and charismatic lizard, but while we celebrate this recovery, we recognize that much more needs to be done to secure their future and that of other Caribbean wildlife,” says Jenny Daltry , Caribbean Alliance Director, Fauna & Flora and Re:wild, said in a statement. “The combined impacts of biodiversity loss and climate collapse are being felt with greater intensity every year in the Caribbean and around the world. We continue to work to help our partners in Jamaica and St. Vincent and the Grenadines recover from the devastation caused by Hurricane Beryl earlier this year.”
Efforts will continue to conserve this biodiversity hotspot in the face of a changing landscape. One of the factors promoting this recovery is the island’s distance from the mainland and the relatively low number of visitors. The team is constantly vigilant to ensure they can respond quickly as more invasive rodents arrive. The continued rewilding here will also require constant maintenance of the island’s flora, including building soil reserves and sowing additional seeds.
“These restoration interventions have cascading effects: they attract insects that help pollinate plants, they attract birds that drop seeds, they provide food and shelter for lizards that also serve as seed dispersers, pollinators and nutrient transporters,” says Mukhida. “We are committed to Sombrero’s recovery, sharing lessons learned and building on successes.”
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