Mona Ground Iguana

The Mona Ground Iguana, Cyclura cornuta stejnegeri, is a subspecies of the rhinoceros iguana and is endemic to Mona Island, Puerto Rico. It is the largest terrestrial iguana in Puerto Rico. They are scattered throughout the entire island, however they only use the southwest part of the island for nesting. They spend most of their lives underground and can be found in talus slopes, caves and sinkholes usually no more than 5-6 feet underground.

These are prehistoric looking lizards capable of reaching 4 feet in length. They have small horns located in their snout. Their color is generally olive to olive gray with slight brown or blue colorations. Juveniles differ from adults in that they have gray transversal bands through their bodies. These bands last approximately until they are 3 years old. Fruits are the preferred and most important source of food. The diet of adults and juveniles differ slightly but not significantly.

The Mona Ground Iguana mates and nests in the southwest of the island where the sand is softer and there is more direct sunlight. Nesting season begins in the second week of June. Usually one female mates with more than one male in the 2 weeks that the mating season lasts. One month later nesting begins. Females will dig a 3 foot long tunnel located 1-2 feet underground where they deposit from 5 to 19 eggs, with 12 being the average. They will guard the nest for several days but they will not provide parental care for the hatchlings which hatch three months later.