Experts Foster Anegada Rock Iguanas Until Ready for Defense Against Cats

Anegada, Cychlora cream, thrives in places that are flat, barren, and salty. The island seems like a tough place to make a living.

Michael Young, who works in iguana conservation for the Virgin Islands National Parks Trust, explained that for the iguana species on the island, the seemingly unbearable landscape is heaven.

The 10-mile-long island is known for its vast coral reefs, sandy beaches, and flocks of flamingos, and has a population of fewer than 300 people.

The iguana, which could grow up to five feet long and weigh 15 pounds, was the largest vertebrate on this planet for millions of years. Despite the iguana's ferocity, it has been brought to its knees by unlikely predators, such as feral cats that prey on juveniles.

There are very few Anegada rock iguanas, unlike the green overflow iguana, which is native to Central and South America and has been widely introduced elsewhere. The pre-settlement population of about 10,000 iguanas had decreased to about 200 by the 1990s.

Conservation Efforts

Kelly Bradley, a conservation biologist at the Fort Worth Zoo who has worked with this iguana since 2001, estimates that native snakes, Puerto Rican runners, and American birds take up to half of the juveniles in the first week.

This is natural; these animals have spent thousands of years together. Non-native feral cats that are effective predators are upsetting the balance. Iguanas are eaten like popcorn, and only a few survive to adulthood.

The cats most likely arrived in the 18th century with colonial settlers and quickly spread across the island. They have no natural predators, and as their population has grown, the iguana population has dwindled to the point where human intervention is required, The Washington Post reports.

Every summer, Young and Bradley scour the countryside for new iguana nests - tunnels leading to deep chambers where they lay their eggs. Finding a single nest can take days.

They build a nest and hang large steel collars to hunt the emerging young, which can number in the hundreds in a good year. They take them to a "scoop" facility, where they are raised in cages for several years until they are old enough to defend themselves against cats. The experts release the reptiles back into the wild once they deem it is ready to stave off or face its feline predator.

The program was able to release 274 iguanas. In the first two years, Bradley kept track of dozens of radios and more than 80% of them survived.

Hurricane Irma hit Anegada in 2017, just before baiting season, when the team did not catch any events. The British Virgin Islands were then closed during the pandemic, while the island was still recovering from the hurricane. Bradley's fieldwork has been limited in recent years due to both events, and she and Young have collected fewer iguanas.

Young says there have been as many as 64 captive iguanas at the starting facility in previous years, but there are now 48. The Virgin Islands National Parks Foundation built the facility, which includes educational panels about iguanas and the island's flora and fauna. Young shows four American tourists around the area when they arrive.