The “farmers of the forest” in Anegada — otherwise known as Anegada rock iguanas — are crucial to the survival of native and endangered plant species, according to Kelly Bradley, a conservation biologist from the Fort Worth Zoo who has studied the reptiles since 2001 in partnership with the National Parks Trust.
“Because the iguanas are the largest vertebrate on Anegada, they have a really powerful relationship with the plant community there,” Mr. Bradley said during a Friday press conference with botanists from the United Kingdom-based Kew Gardens. “They consume all the fruit, then they walk around and go to the bathroom planting seeds all over the place.”
In recent weeks, the biologist has been going out with the Kew scientists and NPT staff to capture data.
“There are relationships you don’t see until you have all this data,” she said. “Now we have all the NPT staff and they’re giving information about what they know about the plants. I’m never happier than when I’m in the field with the botanists.”
Early in the three-year research project the botanists have just concluded, the team was able to update a 10-year-old classification, which resulted in the conclusion that the rock iguana should remain on the International Union for Conservation of Nature’s Red List of Threatened Species.
In order to determine whether an animal population is healthy, Ms. Bradley explained, there are various factors to consider. Males and females, for instance, typically should be evenly distributed, and the animals should be in a wide range of habitats, she said.
She added that she isn’t concerned about overpopulation of the rock iguanas.
“Once that population got above carrying capacity, then it would crash; then it would come back,” she explained. “And that’s what you see in healthy populations. You see this oscillation of having too many, then a crash, then not having enough, then rising. That’s when the system is running correctly.”