The Galapagos Land Iguana resembles the mythical creatures of the past-dragons with long tails, clawed feet and spiny crests. Land Iguanas have a spiky dorsal crest which runs along the neck and back. They are heavily bodied with thick back legs and smaller front legs.
This is one of three species of land iguana found in the Galapagos Islands, with the others being the Santa Fe land iguana (Conolophus pallidus) and the Galapagos pink land iguana (Conolophus marthae). Together, these three species belong to the genus Conolophus. They are part of the large family Iguanidae and are closely related to the marine iguanas, from which they diverged about 8–10 million years ago.
While at one time these lizards were recorded as being abundant in their land, today they are endangered across much of their natural range.
Appearance & Characteristics
Though the exact taxonomy has been disputed many times over the last few years, by current standards there are three recognised species of Land Iguana found in the Galapagos Islands. Each has can be distinguished by it’s colouring, and range.
The Galapagos Land Iguana – ‘Conolophus subcristatus‘ is native to six islands, the Santa Fe Land Iguana ‘Conolophus pallidus‘ is found only on the island of Santa Fe and the Galapagos Pink Land Iguana ‘Conolophus marthae‘ is only found in specific Northern areas of Isabela Island.
The Galapagos variety is the largest of species within its genus, generally measuring over 1 metre (3 feet) long. The male of the species often weighs up to 13 kilograms.
Their yellowish-orange belly and brownish red back make them more colourful then their cousins the Marine Iguana. Their yellowish skin is often adorned with white, black, and brown blotches. They have a short head, powerful hind legs with sharp claws, and despite their intimidating appearance, they are primarily herbivores.
They also have pleurodont teeth (Having the teeth attached by their sides to the inner side of the jaw, as in some lizards) and its tail is quite a bit longer than its trunk.
Common Name | Scientific Name | Size | Weight | Location | Appearance |
Galapagos Land Iguana | Conolophus subcristatus | 0.9-1.5m (3-5 ft) | Up to 13kg (29 lb) | Fernandina, Isabela, Santa Cruz, North Seymour, Baltra, South Plaza | Yellowish-orange with brownish-red |
Santa Fe Land Iguana/ Barrington Land Iguana | Conolophus pallidus | Up to 0.91 m (3 ft) | Up to up to 11 kg (25 lb) | Santa Fe Island | Lighter, uniform color |
Galapagos Pink Land Iguana | Conolophus marthae | Examples measured 1.08 m (3 ft 7 in) | Limited Data – Examples measured 5 kg (11 lb) | Northern Isabela Island | Pink with dark stripes |
Location And Habitat
The Galapagos land iguanas are found in the dry lowlands of the islands of Fernandina, Isabela, Santa Cruz, North Seymour, Baltra, and South Plaza. These islands are part of the Galapagos Province of the Republic Of Ecuador. These iguanas prefer habitats that offer ample sun for basking, such as volcanic rocks.
They live in the drier areas of the islands and in the mornings are found sprawled beneath the hot equatorial sun. However, to escape the heat of the midday sun, they seek the shade of cactus, rocks, trees or other vegetation. At night they sleep in burrows dug in the ground, to conserve their body heat.
Behaviour And Traits Of The Galapagos Land Iguana
Part of the adaptation to the drier environment includes a conservation of energy by slow movement. This makes the animals seem lazy or stupid. Land Iguanas burrow into the ground creating tunnels which provides a place for nesting, shade during the day and protection at night.
The Land Iguanas show a fascinating interaction with Darwin’s Finches, raising themselves off the ground and allowing the little birds to remove ticks. The birds can often be seen sitting on the iguanas’ backs, picking ticks from between their scales, providing relief to the iguanas and food for the birds.
Galapagos Land Iguana Diet
Land Iguanas feed mainly on low-growing plants and shrubs, such as the cactus, as well as fallen fruits and cactus pads, including the spines of the plants. These succulent plants provide them with both food and moisture they require during long, dry periods. While they are primarily herbivorous, some individuals display carnivorous behaviours, eating carrion, and insects such as centipedes when the opportunity arises.
They get most of the water that they need from the prickly-pear cactus, which makes up around 80% of its diet, including all parts of the plant. In the rainy season, they can be found yellow flowers of the genus Portulaca, and drinking from standing pools of water. These water pools are only usually available in the rainy season and fresh water can be quite scarce in the dry season.
Reproduction And Lifespan
Land Iguanas reach maturity between 8 and 15 years of age. Males are territorial and will aggressively defend specific areas, that typically include more than one female. Territorial displays involve rapid nodding of the head and sometimes, biting and tail-thrashing battles.
Following the mating period, the female Iguanas migrate to suitable areas to nest, and will lay between 2 and 25 eggs in a burrow dug in the sandy soil. The female defends the burrow for a short time, to prevent other females from nesting in the same place.
The young Iguanas hatch 3 – 4 months later (90 to 125 days) and take about a week to dig their way out of the nest. If they survive the first difficult years of life, when food is often scarce and predators are a danger, land Iguanas can live long lives, between 60 to 69 years in the wild.
On South Plaza Island, land iguanas and marine iguanas sometimes interbreed, resulting in a hybrid iguana.
Predators And Threats
Charles Darwin visited Galapagos in 1835, he wrote about the abundance of the land iguanas. However, when whalers and settlers started visiting Galapagos in the early 1800’s, they brought with them goats, pigs, dogs, cats and other domestic animals. Over time these animals escaped or were abandoned with drastic results. This had a horrific impact on the native land iguana populations.
Cats hunt the young iguanas and dogs kill adults. Goats wipe out entire areas of vegetation that the iguanas depend on for food. Today, the abundant iguanas that Darwin wrote about on Santiago Island are extinct. On some of the other islands they are nearly gone.
Conservation Status
It’s estimated that there are between 5,000 and 10,000 of these land iguanas left in the Galapagos Islands. The Conolophus subcristatus species is listed as ‘Vulnerable’ on the IUCN Red List, and the latest assessment was carried out in 2020. Conservation efforts have been made to reintroduce the iguana to areas where they were previously extinct, such as Baltra Island.
The other two species of land iguanas in the Galapagos are also in a fragile state. The Galápagos Pink Land Iguana is listed as ‘Critically Endangered’, and the Santa Fe Land Iguana/ Barrington Land Iguana is listed as ‘Vulnerable’.
5 Fun Galapagos Land Iguana Facts For Kids
- The Galapagos land iguana can grow up to 1.5 meters long – that’s longer than most bicycles!
- They have a special – perhaps symbiotic – relationship with birds called Galapagos Finches (Darwin’s Finches). The birds help them by picking off ticks, and in return they get a good feed!
- These iguanas love to eat prickly pear cactus, even the spiky bits!
- They can live for more than 60 years, which is quite old for a lizard.
- Even though they look fierce, they are mostly herbivores and mainly eat plants.