The Cuban Rock Iguana ( _Cyclura nubila_ ) is a large reptile native to Cuba and its surrounding islands. It is recognized for its robust build and adaptations that allow it to thrive in its rocky, coastal environment. This species represents a fascinating aspect of Caribbean biodiversity, making it a subject of interest for enthusiasts and researchers.
Identifying the Cuban Rock Iguana
The Cuban Rock Iguana is a large lizard. Adult males reach lengths of up to 1.5 meters (5 feet) from snout to tail and weigh around 7 kilograms (15 pounds). Females are smaller, two-thirds the size of males. This species is characterized by a stocky body and a powerful tail covered in sharp, keeled scales, which serves as a defense mechanism.
The coloration of these iguanas varies by sex. Males display shades from dark gray to reddish-brown, while females exhibit an olive-green hue with distinct dark stripes or bands. Both sexes have black limbs with pale brown oval spots and solid black feet.
Juveniles are dark brown or green with faint diagonal bands that fade as they mature. They possess a dewlap, a flap of skin under the throat, and a row of spines extending down their back to their thick tail. Their eyes feature a red sclera and golden iris, which provides excellent vision.
Natural Habitat and Lifestyle
The Cuban Rock Iguana inhabits rocky coastal areas across mainland Cuba and its numerous surrounding islets, including Isla de la Juventud. These habitats feature limestone formations, dry forests, and scrubland. A subspecies, _Cyclura nubila caymanensis_, is also found on the Cayman Islands of Little Cayman and Cayman Brac.
These reptiles are diurnal. They are ground-dwelling lizards, though younger individuals may climb trees to escape predators. Cuban Rock Iguanas are known for their burrowing habits, digging shelters near cacti or thistles, providing protection and food. In areas lacking these plants, they create burrows in dead trees, hollow logs, or limestone crevices.
Males are territorial and use head bobbing and lateral displays to defend their areas. Females are more tolerant of each other, except when guarding their nests.
Diet and Reproduction
The Cuban Rock Iguana is primarily herbivorous, with 95% of its diet consisting of plant matter such as leaves, flowers, and fruits from various species, including purslane, prickly pears, and black mangroves. Their robust jaws and flat teeth are adapted for grinding tough plant material. While predominantly plant-eaters, they are also opportunistic omnivores, scavenging on the carcasses of birds, fish, and crabs. Young iguanas may consume more insects, gradually transitioning to an almost entirely vegetarian diet as they mature.
Reproduction occurs during the wet season, with mating in May and June. Males engage in courtship displays, including head-bobbing and dewlap extensions, to attract females. After mating, females lay a single clutch of eggs, numbering between 3 and 30, in June or July.
These eggs, averaging 70-100 grams each, are buried in sandy nests, often in sun-exposed areas. They are sometimes laid in sites previously excavated by Cuban crocodiles. The incubation period lasts 90 to 120 days. Females guard their nests after laying, exhibiting defensive behaviors like head shaking and hissing.
Conservation and Pet Considerations
The Cuban Rock Iguana is listed as Vulnerable by the IUCN Red List, with its wild population declining due to various threats. Habitat loss, degradation, and fragmentation caused by urbanization and agricultural development pose significant challenges to their survival. Predation by introduced species such as feral cats, dogs, pigs, and mongooses also impacts iguana populations, particularly eggs and hatchlings. The illegal pet trade is another threat, due to their appeal to hobbyists, leading to poaching.
Conservation efforts include captive-breeding programs, which bolster their numbers and serve as models for other endangered Caribbean lizards. The species is listed under Appendix I of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), prohibiting commercial international trade in wild-caught specimens. Despite these regulations, illegal trade persists, with animals sometimes obtained without proper CITES permits.
Keeping Cuban Rock Iguanas as pets involves legal and ethical considerations due to their protected status and complex care. As a CITES Appendix I species, acquiring one legally requires proof of captive breeding and proper documentation. These are large lizards, with adults needing substantial enclosure space; a minimum size of 8 feet long by 4 feet wide by 6 feet high is recommended for a single adult.
They require specific environmental conditions, including a basking spot temperature of 115-120°F, a warm side between 85-90°F, and humidity levels of 60-80%. UVB lighting is also necessary for their health. With a potential lifespan of 60-70 years in captivity, owning a Cuban Rock Iguana is a long-term commitment. Their powerful jaws can deliver a strong bite, requiring cautious handling, despite their generally docile temperament.