dcsimg

Lifespan, longevity, and ageing

provided by AnAge articles
Maximum longevity: 15 years (wild)
license
cc-by-3.0
copyright
Joao Pedro de Magalhaes
editor
de Magalhaes, J. P.
partner site
AnAge articles

Conservation Status

provided by Animal Diversity Web

The Galapagos Land Iguana is listed as a threatened species by the World Conservation Union (Baillie and Groombridge 1996). Threats include destruction of eggs and young lizards by introduced rats and cats, and destruction of food plants by introduced goats.

IUCN Red List of Threatened Species: vulnerable

license
cc-by-nc-sa-3.0
copyright
The Regents of the University of Michigan and its licensors
bibliographic citation
Bruin, T. 2000. "Conolophus subcristatus" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Conolophus_subcristatus.html
author
Tami Bruin, Michigan State University
editor
James Harding, Michigan State University
original
visit source
partner site
Animal Diversity Web

Benefits

provided by Animal Diversity Web

No adverse effects.

license
cc-by-nc-sa-3.0
copyright
The Regents of the University of Michigan and its licensors
bibliographic citation
Bruin, T. 2000. "Conolophus subcristatus" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Conolophus_subcristatus.html
author
Tami Bruin, Michigan State University
editor
James Harding, Michigan State University
original
visit source
partner site
Animal Diversity Web

Benefits

provided by Animal Diversity Web

This species was observed by Darwin early in the 19th Century; Darwin noted its similarity to iguanas on the South American mainland, as well as its obvious adaptations to local conditions. These and other observations of Galapagos wildlife contributed in part to Darwin's theory of evolution.

Today the Land Iguanas are an important part of the unique Galapagos fauna, and studies of their biology, as well as conservation programs, are continuing.

license
cc-by-nc-sa-3.0
copyright
The Regents of the University of Michigan and its licensors
bibliographic citation
Bruin, T. 2000. "Conolophus subcristatus" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Conolophus_subcristatus.html
author
Tami Bruin, Michigan State University
editor
James Harding, Michigan State University
original
visit source
partner site
Animal Diversity Web

Trophic Strategy

provided by Animal Diversity Web

The Land Iguana is largely a vegetarian. The prickly pear cactus (Opuntia) is a major food source; the lizard eats the cactus fruit and leaves by moving the cactus around in its mouth until all the spines are worked off (Mattison 1989).

license
cc-by-nc-sa-3.0
copyright
The Regents of the University of Michigan and its licensors
bibliographic citation
Bruin, T. 2000. "Conolophus subcristatus" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Conolophus_subcristatus.html
author
Tami Bruin, Michigan State University
editor
James Harding, Michigan State University
original
visit source
partner site
Animal Diversity Web

Distribution

provided by Animal Diversity Web

The Galapagos Land Iguana is native to the Galapagos Islands, off the coast of Ecuador. It is formerly widely distributed on these islands, though its numbers are now greatly reduced (Mattison 1989, Cogger and Zweifel, 1998).

Biogeographic Regions: oceanic islands (Native ); pacific ocean (Native )

license
cc-by-nc-sa-3.0
copyright
The Regents of the University of Michigan and its licensors
bibliographic citation
Bruin, T. 2000. "Conolophus subcristatus" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Conolophus_subcristatus.html
author
Tami Bruin, Michigan State University
editor
James Harding, Michigan State University
original
visit source
partner site
Animal Diversity Web

Habitat

provided by Animal Diversity Web

The lizards live in land burrows, which offer protection from the hot sun. Many islands on which the iguanas live are quite arid.

Terrestrial Biomes: scrub forest

license
cc-by-nc-sa-3.0
copyright
The Regents of the University of Michigan and its licensors
bibliographic citation
Bruin, T. 2000. "Conolophus subcristatus" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Conolophus_subcristatus.html
author
Tami Bruin, Michigan State University
editor
James Harding, Michigan State University
original
visit source
partner site
Animal Diversity Web

Life Expectancy

provided by Animal Diversity Web

Average lifespan
Status: captivity:
15.0 years.

Average lifespan
Sex: male
Status: captivity:
7.3 years.

license
cc-by-nc-sa-3.0
copyright
The Regents of the University of Michigan and its licensors
bibliographic citation
Bruin, T. 2000. "Conolophus subcristatus" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Conolophus_subcristatus.html
author
Tami Bruin, Michigan State University
editor
James Harding, Michigan State University
original
visit source
partner site
Animal Diversity Web

Morphology

provided by Animal Diversity Web

The Galapagos Land Iguana is yellow or brown in color with spots throughout its ventrum and dorsum. A spikey dorsal crest runs along the neck and back. This is a large (>48 in), heavy bodied lizard, with thick back legs and smaller front legs. There are long, sharp claws on its toes. It has a short blunt head and pleurodont teeth. Its tail is quite a bit longer than its trunk. (Mattison 1989).

license
cc-by-nc-sa-3.0
copyright
The Regents of the University of Michigan and its licensors
bibliographic citation
Bruin, T. 2000. "Conolophus subcristatus" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Conolophus_subcristatus.html
author
Tami Bruin, Michigan State University
editor
James Harding, Michigan State University
original
visit source
partner site
Animal Diversity Web

Reproduction

provided by Animal Diversity Web

These lizards have a mating ritual where the male agressively courts the female. Males defend territories around their burrows that both they and females use as shelter, and most courtship occurs around these burrows. Females are attracted to male's territories with burrows, but these burrows are not used for nesting. (Werner 1982).

Female Land Iguanas lay soft-shelled eggs with permeable shells. About 25 eggs are laid in burrows in moist sand or under leaf litter. On the arid, rocky island of Fernandina, females may travel more than 15 km to find good nest sites, sometimes within the crater of a dormant volcano. When places to lay eggs become scarce, competition between females occurs and some eggs already laid may be disturbed by another iguana (Werner 1983, Mattison 1989). Hatchlings appear in about three to four months, and may take about a week to dig out of the nest cavity (Terraquest 1996).

license
cc-by-nc-sa-3.0
copyright
The Regents of the University of Michigan and its licensors
bibliographic citation
Bruin, T. 2000. "Conolophus subcristatus" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Conolophus_subcristatus.html
author
Tami Bruin, Michigan State University
editor
James Harding, Michigan State University
original
visit source
partner site
Animal Diversity Web

Biology

provided by Arkive
Galapagos land iguanas are active during the day. They maintain their body temperature by basking in the sun to warm up and seeking shade when they become too hot. In the morning they can be found basking, but during the heat of midday they tend to retreat into shade. At night they sleep in burrows which they dig themselves (5). This species is omnivorous but tends to mainly eat plants and the fruits and pads of cactus trees. They may remove the spines with their claws, and these cacti provide them with plenty of moisture during dry spells (2) (5). This species has an interesting relationship with Galapagos finches; the iguanas often raise themselves from the ground and allow the finches to remove ticks from their bodies (2). Males defend territories, with displays involving head bobbing, biting and tail thrashing (5). During courtship, males aggressively court the females (4). After mating, the females set off on a migration to suitable egg-laying habitat. On Ferdinanda Island, females are known to travel up to 15 km to reach a suitable nesting site (4). They then lay two to 20 eggs in a 50 cm deep burrow. The nest site is guarded for a number of days after laying, in order to prevent other females from laying in the same place and damaging the eggs (5). The young hatch after 85 to 110 days; it then takes them up to a week to dig their way out of the burrow (5). Maturity is reached between eight and 15 years. If they survive the first years of life, when they are most vulnerable to predation and food scarcity, land iguanas can live for up to 50 years (2).
license
cc-by-nc-sa-3.0
copyright
Wildscreen
original
visit source
partner site
Arkive

Conservation

provided by Arkive
In 1976, wild dogs wiped out the last colonies of land iguanas around Conway Bay on Santa Cruz Island. This prompted the Charles Darwin Research Station (CDRS) and the Galapagos National Park Service (GNPS) to initiate an emergency rescue scheme for the 60 remaining survivors. They then discovered that a similar level of destruction was occurring on Isabella Island. The GNPS and CDRS established a recovery programme, including a captive breeding scheme based on Santa Cruz. The captive breeding programme continues today, and land iguanas are returned to the wild when they reach a size beyond which they are safe from cat predation (2) (6). This breeding programme is accompanied by a campaign to work towards the eradication and tighter control of introduced animals. Other important measures include the maintenance of suitable habitat for the species, and continued monitoring of the populations (2).
license
cc-by-nc-sa-3.0
copyright
Wildscreen
original
visit source
partner site
Arkive

Description

provided by Arkive
There are two species of land iguana found in the Galapagos; this species Conolophus subcristatus, is found on six islands and Conolophus pallidus is found only on Santa Fe (2). This species is very large, growing to lengths of over a meter (2). The short head is blunt and the back legs are thick and powerful, with long sharp claws on the toes (4). It is yellowish in colour with blotches of white, black, rust and brown (5) and a row of spines passes along the centre of the neck and back (4).
license
cc-by-nc-sa-3.0
copyright
Wildscreen
original
visit source
partner site
Arkive

Habitat

provided by Arkive
This iguana lives in the drier areas of the islands on which they occur, in scrubby habitats (5) (4). Females require access to areas of sandy or loose soil in which to lay their eggs; some females even use the ash around dormant volcanic craters (4).
license
cc-by-nc-sa-3.0
copyright
Wildscreen
original
visit source
partner site
Arkive

Range

provided by Arkive
Land iguanas are endemic to the Galapagos Islands off the coast of Ecuador (4). Conolophus subcristatus is native to six islands (2). In 1835 when Charles Darwin first went to the Galapagos, land iguanas were extremely numerous; he wrote: “I cannot give a more forcible proof of their number, then by stating that when we were left at Santiago Island, we could not for some time find a spot free from their burrows on which to pitch our single tent”. Sadly, this once thriving Santiago Island population has become completely extinct (6).
license
cc-by-nc-sa-3.0
copyright
Wildscreen
original
visit source
partner site
Arkive

Status

provided by Arkive
Classified as Vulnerable (VU D2) by the IUCN Red List (1) and listed on Appendix II of CITES (3).
license
cc-by-nc-sa-3.0
copyright
Wildscreen
original
visit source
partner site
Arkive

Threats

provided by Arkive
In the early 1800s, whalers and settlers came to the Galapagos Islands. It is likely that they ate land iguanas, but the most serious problem they caused resulted from the introduction, both accidental and deliberate, of predators such as cats and dogs and domestic animals such as goats and pigs (6). Introduced animals are still the main threat facing this species today (2). Cats and rats hunt eggs and young iguanas and introduced goats destroy food plants (4). The natural predators of land iguanas include hawks, herons, and snakes, all of which cannot prey on young after they reach around one year of age, as they become too large. However, cats can continue to kill young iguanas until they reach three or four years of age; cat predation is a huge problem preventing the natural success of the species (5).
license
cc-by-nc-sa-3.0
copyright
Wildscreen
original
visit source
partner site
Arkive

Galapagos land iguana

provided by wikipedia EN

The Galapagos land iguana (Conolophus subcristatus) is a species of lizard in the family Iguanidae. It is one of three species of the genus Conolophus. It is endemic to the Galápagos Islands (Ecuador), in the dry lowlands of Fernandina, Isabela, Santa Cruz, North Seymour, Baltra, and South Plaza Islands.[1][2][3]

Taxonomy

The land iguanas in the Galápagos vary in morphology and coloration among different populations.[4] In addition to the relatively widespread and well-known Galapagos land iguana (C. subcristatus), there are two other species of Conolophus: the Galapagos pink land iguana (C. marthae) from northern Isabela Island and the Santa Fe land iguana (C. pallidus) from Santa Fe Island.[4][5] Based on mtDNA, the land iguanas and marine iguana diverged about 8–10 million years ago.[6][7] Within the land iguana genus, the oldest split based on mtDNA, about 5.7 million years old, is between C. subcristatus and C. marthae.[7][8] A more recent study that included both mtDNA and nuclear DNA indicates that the land iguanas split from the marine iguana about 4.5 million years ago, and among the land iguanas C. subcristatus and C. marthae split from each other about 1.5 million years ago.[9] The differentiation between the last two species, C. subcristatus and C. pallidus, is less clear and it has been questioned whether they are separate species.[4] Based on mtDNA and cytochrome b, they fall into three monophyletic groups: C. subcristatus of western islands (Isabela and Fernandina), C. subcristatus of central islands (Santa Cruz, Baltra and South Plaza) and C. pallidus. Although the exact pattern is uncertain, it is possible that C. pallidus is closer to one of the C. subcristatus groups than the two C. subcristatus groups are to each other.[8]

Its specific name subcristatus is derived from the Latin words sub meaning "lesser" and cristatus meaning "crested", and refers to the low crest of spines along the animal's back, which is not as tall as in most iguanas.

Anatomy and morphology

Charles Darwin described the Galapagos land iguana as "ugly animals, of a yellowish orange beneath, and of a brownish-red colour above: from their low facial angle they have a singularly stupid appearance."[10] The Galapagos land iguana grows to a length of 0.9 to 1.5 m (3–5 ft) with a body weight of up to 11 kg (25 lb), depending upon which island they are from.[11][12] Being cold-blooded, they absorb heat from the sun by basking on volcanic rock, and at night sleep in burrows to conserve their body heat.[11] These iguanas also enjoy a symbiotic relationship with birds; the birds remove parasites and ticks, providing relief to the iguanas and food for the birds.[2][13]

Diet and longevity

 src=
Feeding
 src=
Feeding on fallen cactus pads

Land iguanas are primarily herbivorous; however, some individuals have shown that they are opportunistic carnivores supplementing their diet with insects, centipedes and carrion.[2] Because fresh water is scarce on the islands it in habits, the Galapagos land iguana obtains majority of its moisture from the prickly-pear cactus that makes up 80% of its diet: fruit, flowers, pads, and even spines.[2][11] During the rainy season it will drink from available standing pools of water and feast on yellow flowers of the genus Portulaca.[11][13]

the Galapagos land iguana has a 60to 69-year lifespan.[2][12]

Reproduction

 src=
Basking

Galapagos land iguanas become sexually mature anywhere between eight and fifteen years of age, depending on which island they are from.[2] Mating season also varies between islands, but soon after mating, the females migrate to sandy areas to nest, laying 2–20 eggs in a burrow about 50 cm (20 in) deep.[2] The eggs hatch anywhere from 90 to 125 days later.[2][12]

On South Plaza Island, where the territories of marine iguanas and land iguanas overlap, the two sometimes interbreed, resulting in a hybrid iguana that shows a mixture of features from each species.[2] The most likely unions tend to be between male marine iguanas and female land iguanas. Despite their long separation time and their being two distinct species from different genera, the offspring are viable, although likely sterile.[2][4]

Population

It is estimated that between 5,000 and 10,000 land iguanas are found in the Galapagos.[2] These iguanas were so abundant on Santiago Island at one time that naturalist Charles Darwin remarked when it was called King James Island that "...when we were left at James, we could not for some time find a spot free from their burrows on which to pitch our single tent".[11][14] In the years since then, entire populations (including all the animals on Santiago Island) have been wiped out by introduced feral animals such as pigs, rats, cats, and dogs.[2][11]

Evolutionary history

Researchers theorize that Galapagos land iguanas and marine iguanas evolved from a common ancestor since arriving on the islands from South America, presumably by rafting.[15][16] The marine iguana diverged from the land iguana some 8 million years ago, which is older than any of the extant Galapagos islands.[6] It is therefore thought that the ancestral species inhabited parts of the volcanic archipelago that are now submerged. The two species remain mutually fertile in spite of being assigned to distinct genera, and they occasionally hybridize where their ranges overlap.

Recovery efforts

 src=
Male
 src=
Yellow land iguana at the Charles Darwin Research Station
 src=
Galapagos land iguana on North Seymour Island.

Beginning in the early 1990s, the Galapagos land iguana has been the subject of an active reintroduction campaign on Baltra Island. These animals became extinct on Baltra by 1954, allegedly wiped out by soldiers stationed there who shot the iguanas for amusement.[2][13] However, in the early 1930s, William Randolph Hearst had translocated a population of land iguanas from Baltra to North Seymour Island, a smaller island just a few hundred metres north of Baltra, because he could not understand why no iguanas were present there. Hearst's translocated iguanas survived, and became the breeding stock for the Charles Darwin Research Station captive breeding program that has successfully reintroduced the species to Baltra and a number of other areas.[2] Visitors today frequently see iguanas on both the runway of the Baltra airport or while they cross the road.

References

  1. ^ a b World Conservation Monitoring Centre (1996). "Conolophus subcristatus". IUCN Red List of Threatened Species. IUCN. 1996: e.T5240A11121212. doi:10.2305/IUCN.UK.1996.RLTS.T5240A11121212.en.CS1 maint: uses authors parameter (link)
  2. ^ a b c d e f g h i j k l m n "Land iguanas" (PDF). Charles Darwin Research Station Fact Sheet. Charles Darwin Foundation for the Galapagos Islands. 2006. Archived from the original (PDF) on 2007-06-06. Retrieved 2007-10-14.
  3. ^ Swash, A.; and R. Still (2000). Birds, Mammals & Reptiles of the Galápagos Islands. Yale University Press. pp. 118–119. ISBN 0-300-08864-7.CS1 maint: uses authors parameter (link)
  4. ^ a b c d Rassmann, Kornelia; Markmann, Melanie; Trillmich, Fritz; Tautz, Diethard (2004), "Tracing the Evolution of the Galapagos Iguanas", Iguanas: Biology and Conservation, California: University of California Press, pp. 71–83, ISBN 978-0-520-23854-1
  5. ^ Gentile, Gabriele; Anna Fabiani; Cruz Marquez; Howard L. Snell; Heidi M. Snell; Washington Tapia; Valerio Sbordonia (2009). "An overlooked pink species of land iguana in the Galapagos". Proceedings of the National Academy of Sciences of the United States of America. National Academy of Sciences of the United States of America. 106 (2): 507–11. doi:10.1073/pnas.0806339106. PMC 2626733. PMID 19124773.
  6. ^ a b "Explaining the Divergence of the Marine Iguana Subspecies on Espa". amnh.org.
  7. ^ a b Black, Richard (5 January 2009). "Pink iguana rewrites family tree". BBC News. BBC. Retrieved 20 May 2017.
  8. ^ a b Gentile; Fabiania; Marquez; Snell; Snell; Tapia;and Sbordonia (2009). "An overlooked pink species of land iguana in the Galápagos". Proceedings of the National Academy of Sciences of the United States of America. National Academy of Sciences of the United States of America. 106 (2): 507–511. doi:10.1073/pnas.0806339106. PMC 2626733. PMID 19124773.CS1 maint: uses authors parameter (link)
  9. ^ MacLeod, A.; A. Rodríguez; M. Vences; P. Orozco-terWengel; C. García; F. Trillmich; G. Gentile; A. Caccone; G. Quezada; S. Steinfartz (2015). "Hybridization masks speciation in the evolutionary history of the Galápagos marine iguana". Proceedings of the Royal Society B. 282 (1809): 20150425. doi:10.1098/rspb.2015.0425. PMC 4590447. PMID 26041359.
  10. ^ Darwin, Charles (1989), The Voyage of the Beagle: Charles Darwin's Journal of Researches, New York: Penguin Classics, p. 401, ISBN 978-0-14-043268-8
  11. ^ a b c d e f Rogers, Barbara (1990), Galapagos, New York: Mallard Press, p. 51, ISBN 978-0-7924-5192-1
  12. ^ a b c Rosenthal, Ellen (1997), "Days and nights of the iguana: in the Galapagos, a devoted pair work to save land iguanas", Animals, archived from the original on 2017-03-12
  13. ^ a b c Kricher, John (2006), Galapagos: A Natural History, New Jersey: Princeton University Press, pp. 9, 51, 91, 200, ISBN 978-0-691-12633-3
  14. ^ Darwin, Charles (1839), Narrative of the surveying voyages of His Majesty's Ships Adventure and Beagle between the years 1826 and 1836, describing their examination of the southern shores of South America, and the Beagle's circumnavigation of the globe. Journal and remarks., London: Henry Colburn, p. 488
  15. ^ Rassmann, K.; Tautz, D.; Trillmich, F.; Gliddon, C. (1997). "The micro – evolution of the Galápagos marine iguana Amblyrhynchus cristatus assessed by nuclear and mitochondrial genetic analysis". Molecular Ecology. 6 (5): 437. doi:10.1046/j.1365-294X.1997.00209.x.
  16. ^ Marine Iguana. marinebio.org.

 title=
license
cc-by-sa-3.0
copyright
Wikipedia authors and editors
original
visit source
partner site
wikipedia EN

Galapagos land iguana: Brief Summary

provided by wikipedia EN

The Galapagos land iguana (Conolophus subcristatus) is a species of lizard in the family Iguanidae. It is one of three species of the genus Conolophus. It is endemic to the Galápagos Islands (Ecuador), in the dry lowlands of Fernandina, Isabela, Santa Cruz, North Seymour, Baltra, and South Plaza Islands.

license
cc-by-sa-3.0
copyright
Wikipedia authors and editors
original
visit source
partner site
wikipedia EN