Land Iguana: At a Glance

Scientific name: Conolophus subcristatus
Taxonomy: Reptilia > Squamata > Iguanidae > Conolophus
Conservation Status: Vulnerable (local populations vary; threats include introduced predators and habitat degradation)
Endemic to the Galapagos: Yes
Population: Estimated between 5,000–10,000 individuals
Size: Up to 1 m in length; up to 13 kg
Lifespan: Believed to exceed 60 years in some populations
Diet: Mostly pads and fruits of the Opuntia cactus; juveniles eat insects and small arthropods
Where to see them: South Plaza, Santa Cruz, North Seymour, and other arid islands

Darwin and Iguanas

Darwin was famously unimpressed by Galapagos reptiles. He described land iguanas as “ugly animals” with a “singularly stupid appearance,” and reserved even harsher words for their marine relatives. Fortunately for today’s visitors, his views haven’t stood the test of time.

The “Prehistoric” Look

Modern travellers consistently reach for another comparison: dinosaurs. With their heavy heads, spiny crests, thick limbs and deep-set eyes, land iguanas carry an undeniably ancient look. They are powerful reptiles, often basking in the heat of the day before retreating into burrows they dig in soft tuff or sandy soils.

Distribution and Habitat

Land iguanas are widespread across the archipelago, though populations have fluctuated dramatically over the last two centuries. They typically live in small colonies in arid zones and lava landscapes, sometimes restricted to isolated pockets such as the old tuff cone of Cerro Dragón on Santa Cruz. On islands like Fernandina, females make long seasonal migrations to reach communal nesting sites, journeys that can begin within the caldera itself.

The introduction of pigs, dogs, cats and rats decimated many historic populations, including the original Baltra colony. That lineage was re-established after individuals from North Seymour were reintroduced.

Feeding and Behaviour

Adult land iguanas are mostly vegetarian, feeding heavily on Opuntia pads and fruits, as well as other tough desert plants. Juveniles eat mainly insects and other arthropods before gradually shifting to a plant-based diet. They are opportunistic and have been observed raiding the nests of finches for hatchlings.

Mating occurs toward the end of the year, with egg-laying from January to March. Courtship is forceful: males seize females by the nape before copulation. Nesting and hatching seasons expose eggs and juveniles to numerous predators, from frigatebirds to invasive mammals.

How Iguanas Evolved

Marine and land iguanas share an ancestor believed to have rafted from mainland South America millions of years ago. As the archipelago formed and shifted, populations became isolated on different islands, giving rise to the distinct lineages seen today.

Hybrid Iguanas (South Plaza)

South Plaza Island, in the centre of the Galapagos archipelago, is the only site where land and marine iguanas naturally overlap. The islet is very small, and with no barriers between territories, occasional hybridisation occurs. These hybrids are typically dark with pale irregular bands, have small crests, and tend to resemble marine iguanas in head shape. They are terrestrial, likely sterile and rare to find.

Other Land Iguana Species

Santa Fé Land Iguana (Conolophus pallidus)

Restricted exclusively to Santa Fé Island, this iguana was long recognised as a distinct species due to its paler, almost sandy coloration and longer dorsal spines. Males often have dull yellow tones with darker patches.

Pink Iguana (Conolophus marthae)

First observed in 1986 and formally described in 2009, the Pink Iguana remains one of the rarest reptiles on Earth, with a population of roughly 100 individuals. They inhabit the upper slopes of Volcán Wolf on northern Isabela (off limits to visitors). Their striking pink bodies with irregular black banding are unlike any other iguana in the archipelago.

The species lives entirely within a remote, protected area which is closed to visitors.