Land Iguana Facts | Galapagos Islands Wildlife Guide
The two species of land iguanas—Galapagos and Santa Fe—look almost identical; they are yellowish in color and bigger than their marine relatives.
Physical Characteristics
- Galapagos land iguana adults may weigh up to 175 pounds and may be 39 inches long
- The similar-looking Santa Fe land iguanas, limited only to Santa Fe Island, are, on average, slightly bigger and more yellow than the Galapagos land iguana. They have more pronounced spines, and they can exceed 3.3 feet in length
- A spikey dorsal crest runs along their neck and back
- Yellowish in color with splotches of black, white and brown
- Toes have long, sharp claws
- Noses are short and blunt
Range and Habitat
Galapagos land iguanas are endemic to the Galapagos Islands, and they are found on the islands of South Plaza, Isabela, Santa Cruz, Fernandina, Hood and North Seymour, with South Plaza offering the best viewing opportunities. Land iguanas formerly existed on most of the other islands in the archipelago as well, but hunting and competition by introduced animals such as goats, rats, pigs and pet cats and dogs, which prey on iguana eggs, caused their demise. They prefer drier, scrubbier areas and live in burrows.
Feeding Habits
The preferred food of Galapagos land iguanas and Santa Fe land iguanas is the prickly pear cactus. They are sometimes seen standing on their hind legs while they try to reach the pads and yellow flowers of the succulent. Their mouths are incredibly leathery, enabling them to eat the cactus pads whole without removing the spines. They will also eat insects and carrion, if those can be found.
Behavior and Communication
Land iguanas live in small colonies, though sometimes they can be found alone. Males will engage in head-butting to defend their territories because they are highly territorial. Land iguanas are known to live for at least 60 years.
Breeding and Reproduction
Land iguanas reach sexual maturity between 6 and 10 years of age. Males aggressively court females, and then the females will search extensively for suitable nesting areas. In fact, some will travel up to nine miles until they find the right place to lay their eggs. Then, they dig a hole 18 inches deep and may lay from 2 to 25 eggs. They will defend their nests for a few days, at least, to make sure other females will not lay in the same place. Hatching occurs after approximately 100 days of incubation.
Conservation
Land iguanas are a threatened species because of introduced rats and cats, mainly. Darwin wrote that when he and his team explored Santiago Island, they could not find an appropriate place to pitch their tents, as there were too many land iguana burrows. Sadly, the iguana population on Santiago Island has since disappeared. Goats also invade their habitat, potentially eating up their food supplies. Conservation efforts seek to manage domestic and feral animals, as well as protect their habitats in general.