Jamaican iguana

Photograph by Joel Sartore, National Geographic Photo Ark
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The critically endangered Jamaican iguana is the largest animal native to Jamaica. It faces a variety of threats, including invasive species and loss of its habitat.

Photograph by Joel Sartore, National Geographic Photo Ark

What is the Jamaican iguana?

Jamaican iguanas are darkly colored reptiles with scaly skin, long tails, and triangular stripes running along the length of their spines. Their scale color can range from gray to blue and green. The iguanas are the largest animals native to Jamaica.

Habitat and diet

Historically, these iguanas used to inhabit a much larger range on the southern coasts of Jamaica, but today they can only be found in a location known as the Hellshire Hills. This dry forest full of rocky, limestone outcrops is considered one of the world’s most threatened ecosystems, and iguanas can really only be found in its most remote corners.

With long toes and sharp claws, Jamaican iguanas can haul themselves into trees where they eat leaves, fruit, and flowers. While plants make up most of their diets, the reptiles will also eat snails, insects, and other small animals when available.

Reproduction

After mating, female Jamaican iguanas start digging burrows to test out soil composition. Excavations may begin long before the actual egg-laying, as each female searches for the right spot to lay her eggs. When she’s ready, the female lays between six and 20 eggs in a clutch and then covers them back up with sand and dirt.

Unlike sea turtles, which return to the ocean after egg-laying, the female iguana’s work is not yet done. For up to two weeks, the female remains at the nesting site to guard it from other female iguanas. When confronted, the iguana extends the fold of skin beneath her neck, known as a dewlap, as a way to warn off intruders. But if the others fail to take the hint, the female will actually bite and chase other females in an effort to keep her eggs safe from disturbance.

After 85 to 87 days, the young iguanas hatch from their eggs and claw their way to the surface. Then, they must do their best to survive on their own—a feat made easier by the little ones’ tendency to hide out in the trees.

Threats to survival

Jamaican iguanas face an array of threats in the few enclaves of forest where they remain. Chief among these are invasive species like the mongoose, which preys on iguana eggs and young, as well as cats, which have been observed hunting and killing juvenile iguanas. Feral hogs may also be a problem, as they have been documented tearing up iguana nests on other islands. What’s more, the dogs locals use to hunt hogs are dangerous, too, as one of the few animals on Jamaica that can take down a full grown iguana.

With just about 200 of the reptiles left in the wild, and all of those restricted to under four square miles of remote dry forests, the iguanas may be particularly susceptible to habitat loss, as well. Cutting down trees for use in the charcoal industry is an important source of income for the people who live near Jamaican iguanas, and this practice has already degraded as much as a third of the species’ habitat, according to the International Union for Conservation of Nature (IUCN).

Some have also proposed opening the Hellshire Hills to other kinds of development, such as limestone mining, housing settlements, and tourism operations, all of which would further imperil these rare lizards.

Conservation

Today, the fact that there are still Jamaican iguanas scurrying around the wild is considered a conservation success story. This is because most experts believed the species had gone extinct back in the 1940s.

But a single sighting by a hunter in 1970 hinted that the species hadn’t blinked out quite yet. Then another sighting in 1990 confirmed that Jamaican iguanas were still hiding out in the Hellshire Hills and spurred conservation action.

The first step in saving the iguanas was to protect them from their invasive predators. Extensive trapping efforts helped reduce the mongoose population in the reptile’s habitat, and releases of captive-bred iguanas further bolstered the population so that it could grow to where it is today.

The IUCN still considers the Jamaican iguana to be critically endangered. However, between 1991 and 2013, reports indicated that the number of nesting females and annual hatchlings increased more than six-fold, providing new hope for the species.