Galapagos Land Iguana

Galapagos Land Iguana
Photo by Peter Wilton

Among the amazing animals that can be found on the famous Galapagos Archipelago are two species of land iguanas. The more common of the two is the Conolophus subcristatus and it can be found on Fernandina Island, Isabela Island, Santa Cruz Island, North Seymour Island, Hood Island and South Plaza Island. The second is the Conolophus pallidus and it can only be found on Sante Fe Island.

Galapagos land iguanas are yellow, orange or a mix of the two. They have blunt heads and long, tapering tails. These iguanas have short legs and long, sharp claws. A row of spines runs down the center of the neck and down the back. They are relatively large iguanas with adult males being up to 3.2 feet long and weighing up to 28 pounds.

Galapagos land iguanas do have specific time frames for breeding. However, this time depends on the island on which the iguana dwells. After mating, the female iguana will wander off to dig a nest in sandy or loose soil, which she will protect for a few days before abandoning it. The female lays anywhere from 2-25 eggs; the eggs will incubate for three to four months. When the eggs hatch, it will take the young about one week to dig their way out of the nest. The young are very vulnerable to predation, but may live more than 50 years, if they get past the first couple. It will take them between 8 and 15 years to reach adulthood, depending on their size.

Galapagos land iguanas are omnivorous. However, their primary source of food is the plant life of their respective islands, particularly, cactus and fallen fruit. Younger iguanas are a source of food for other animals on the islands such as cats, heron, hawks and snakes. Cats will eat the eggs and can feed on land iguanas until they are about four years old, at which time they become too big for the cats. The rest of the animal’s predators can only eat smaller specimens that are up to a year old. Adult Galapagos land iguanas have no natural predators.

These animals are only active during daylight hours. They bask in the sun during the morning, but spend the hottest hours hiding in the shade. At night they sleep in burrows which they dig in the earth. Males of these two species are territorial and do display aggression. When their territory is being encroached upon by another male, they may bob their head up and down or bite the other animal. Another interesting behavior that these animals display is their symbiotic relationship with Darwin’s finches. When a Galapagos land iguana has ticks, it may lift its body up off the ground so that one of these birds can eat the ticks.

Unfortunately, like so many other species on these beautiful islands, the Galapagos land iguana is in need of conservation. They are listed as Vulnerable on the IUCN Red List and they are threatened by invasive species. There are conservation efforts underway at this time. However, the species population has dwindled so much that some of the islands where they were abundant are no longer host to these creatures. Hopefully with a little care on our part and a little more effort for their sake, this won’t happen on any more of the islands in the Galapagos.

Sources

Galapagos Land Iguanas, retrieved 11/07/09, gct.org/iguana.html

Galapagos Land Iguana, arkive.org/galapagos-land-iguana/conolophus-subcristatus/info.html