Back in 1992, no one could predict that a single project with Cuban iguanas at Guantanamo Bay would lead to an extensive research program in the Caribbean to rescue critically endangered rock iguanas from extinction. It all began when Allison Alberts, then a young postdoctoral fellow with San Diego Zoo Global, joined fellow researchers Tandora Grant and Jeff Lemm in Cuba. Next, they went to Jamaica for a few days to participate in a recovery planning program that eventually led to the formation of the IUCN Iguana Specialist Group.
These were exciting years for conservation researchers because Jamaican iguanas were rediscovered in 1990—after being declared extinct in the mid-1940s—when a tiny population of fewer than 50 was found in the Hellshire Hills near Kingston. Soon after, rock iguana conservation programs were launched, with the Association of Zoos and Aquariums recommending assurance populations of endangered iguanas in zoos, to protect against catastrophic loss in the wild. In 2000, Glenn Gerber joined the team as a postdoctoral fellow, setting up projects in several countries and eventually overseeing the Caribbean field program that included successive postdoctoral fellows Charles Knapp, Stesha Pasachnik, and Giuliano Colosimo. In addition to Cuba and Jamaica, our teams have worked in The Bahamas, Turks and Caicos, Puerto Rico, Dominican Republic, Cayman Islands, Dominica, and the British Virgin Islands.
Working with the least endangered rock iguanas in Cuba, the team was soon posing conservation questions and refining techniques like egg collection and incubation. They also pioneered a new technique in the region for rock iguanas called headstarting: hatchlings would be raised in protected care for several years until they weighed more and had a better chance of evading predators, such as mongooses and cats, when released. Tandora says that “iguanas are resilient—they adapt well to reintroduction programs—and know immediately where to find food, dig nests, find mates. You don’t need to prepare them for release like birds and mammals.”
The first step is to find wild nests and wait for hatchlings to emerge, then add transponder chips so they can be tracked throughout their life, including annual health checks—and iguanas can live as long as 60 years. The goal is to raise them at island facilities and release headstarted youngsters. For example, Jamaican iguanas need to weigh at least 2 pounds before release, which could take 3 to 7 years.
We look for relatedness among founders living in zoos and in island facilities as well as any changes in genetic diversity from the original groups after years of headstarting and translocations to new islands. Knowing how these iguanas are related determines breeding pairs and release strategies, which are maintained in a studbook format for each species. Tandora manages the pedigree analysis for Jamaican and Grand Cayman blue iguanas—both species are considered among the rarest lizards in the world. At the Griffin Reptile Conservation Center, Jeff Lemm oversees our breeding program for Jamaican, Grand Cayman, and Anegada iguanas.
In the Turks and Caicos, which has over 200 islands, Glenn Gerber works with the smallest rock iguana species and oversees reintroductions and long-term population studies. Volunteers are essential for helping with this fieldwork that includes navigating between islands on our dedicated research vessel: some on his team have made 25 trips with Glenn so far. He has also worked extensively on Little Cayman and on Anegada, where he and Jeff Lemm began headstarting youngsters in 1997.
After working together for 25 years, the team is optimistic about the future for iguanas. As island nations take on responsibilities for restoring habitat and predator control, and technologies and education improve, iguanas have become flagship species for conservation in the region. For the team, this is their life’s work. Along with dedicated partners and buy-in from islanders and their governments, saving an endangered species will always depend on those who share a long-term vision.