Fiji Crested Iguana
Encyclopedia
The Fiji crested iguana (Brachylophus vitiensis) is a critically endangered
species of iguana
native to some of the northwestern islands of the Fiji
ian archipelago, where it is found in dry forest.
name, Brachylophus, is derived from two Greek words: brachys (βραχῦς) meaning "short" and lophos (λοφος) meaning "crest" or "plume", denoting the short spiny crests along the back of this species. The specific name, vitiensis, is a Latin
adjective derived from the Latin word for Fiji: Viti.
The species is closely related to the Fiji banded iguana and B. bulabula
. The genus Brachylophus has been suggested to be the descendants of a more widespread lineage of (now extinct) Old World
iguanids that diverged from their New World
relatives in the Paleogene
. Alternatively, the ancestors of these iguanas may have rafted
9000 km west across the Pacific Ocean from the Americas, where their closest relatives are found.
The discovery of Brachylophus vitiensis began when Dr. John Gibbons of the University of the South Pacific
was invited to the screening of the movie Blue Lagoon
. The director filmed part of the movie on a remote island and included shots of the native wildlife to enhance the feel of the movie, including a large colorful iguanid. Gibbons, who had been studying the Fiji banded iguana at the time, travelled to the island and identified it as a distinct species.
, Monuriki
, and Macuata
. Yadua Taba holds the highest concentration of the species, containing approximately 98% of all individuals, which is estimated to be 6,000 animals. This is the only legally protected population, as Yadua Taba is a National Trust of Fiji reserve and lacks the feral
goat
s which have destroyed the lizard's habitat on other islands.
The Fiji crested iguana is a large stocky lizard distinguished from the Fiji banded iguana by the presence of three narrow, cream to white colored bands on males, rather than the broader bluish bands of the latter species. These whitish bands often have chevrons of black scales close to them. Brachylophus vitiensis is distinguished by its larger size growing to 76 centimetres (29.9 in) in length and weighing as much as 300 gram (0.661386786554633 lb). It is further distinguished by the presence of a taller spiny "crest" on its back with spines as long as 1.5 centimetre (0.590551181102362 in) running from the nape of the neck to the base of its tail, and its ability to rapidly change color from green to black when aroused. It uses this ability when threatened. Along with turning black it opens its mouth and lunges at its attacker.
When Fiji crested iguanas first hatch from their egg
s they are dark green, but after several hours their skin becomes bright emerald green and narrow white bands can be seen along their body.
Their eyes are reddish orange or pinkish gold in color.
and as such its name is not allowed to be mentioned in the presence of women or the offender may be beaten with a stick. The majority of Fijians, however, are terrified of the crested iguana because of its behavior when threatened.
s threaten the regeneration of native food trees for the iguanas, but the government of Fiji has taken steps to eradicate the trees.
A secondary threat is introduced predators in the forms of rat
s, mongoose
s, and cat
s which prey on the iguanas and their eggs. Additionally the iguana has been hunted as a food source and for the illegal animal trade.
In 2002, five adult iguanas were stolen from the sanctuary, but Fiji Custom officers caught the smuggler before he boarded his international flight. Since this incident, tourist visits to the sanctuary have been prohibited and only researchers are permitted to visit the island. In order to protect iguanas in the sanctuary from diseases and parasites, it is not permitted to return to the island any lizard that has been removed.
Critically endangered
Version 2010.3 of the IUCN Red List of Threatened Species identified 3744 Critically Endangered species, subspecies and varieties, stocks and subpopulations.Critically Endangered by kingdom:*1993 Animalia*2 Fungi*1745 Plantae*4 Protista-References:...
species of iguana
Iguanidae
Iguanidae is a family of lizards, composed of iguanas and related species.-Classification of Iguanidae:Two different classification schemes have been used to define the structure of this family. These are the "traditional" classification and the classification presented by Frost et al. .Frost et...
native to some of the northwestern islands of the Fiji
Fiji
Fiji , officially the Republic of Fiji , is an island nation in Melanesia in the South Pacific Ocean about northeast of New Zealand's North Island...
ian archipelago, where it is found in dry forest.
Taxonomy and etymology
The genericGenus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
name, Brachylophus, is derived from two Greek words: brachys (βραχῦς) meaning "short" and lophos (λοφος) meaning "crest" or "plume", denoting the short spiny crests along the back of this species. The specific name, vitiensis, is a Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
adjective derived from the Latin word for Fiji: Viti.
The species is closely related to the Fiji banded iguana and B. bulabula
Brachylophus bulabula
Brachylophus bulabula is a species of iguanid lizard endemic to some of the larger central and northwestern islands of Fiji , where it occurs in Fijian wet forest. It was discovered by a team led by a scientist from the Australian National University in 2008...
. The genus Brachylophus has been suggested to be the descendants of a more widespread lineage of (now extinct) Old World
Old World
The Old World consists of those parts of the world known to classical antiquity and the European Middle Ages. It is used in the context of, and contrast with, the "New World" ....
iguanids that diverged from their New World
New World
The New World is one of the names used for the Western Hemisphere, specifically America and sometimes Oceania . The term originated in the late 15th century, when America had been recently discovered by European explorers, expanding the geographical horizon of the people of the European middle...
relatives in the Paleogene
Paleogene
The Paleogene is a geologic period and system that began 65.5 ± 0.3 and ended 23.03 ± 0.05 million years ago and comprises the first part of the Cenozoic Era...
. Alternatively, the ancestors of these iguanas may have rafted
Rafting event
Oceanic dispersal is a type of biological dispersal that occurs when organisms transfer from one land mass to another by way of a sea crossing on large clumps of floating vegetation. Such matted clumps of vegetation are often seen floating down major rivers in the tropics and washing out to sea,...
9000 km west across the Pacific Ocean from the Americas, where their closest relatives are found.
The discovery of Brachylophus vitiensis began when Dr. John Gibbons of the University of the South Pacific
University of the South Pacific
The University of the South Pacific is a public university with a number of locations spread throughout a dozen countries in Oceania. It is an international centre for teaching and research on Pacific culture and environment. USP's academic programmes are recognised worldwide, attracting students...
was invited to the screening of the movie Blue Lagoon
The Blue Lagoon (1980 film)
The Blue Lagoon is a 1980 American romance and adventure film directed by Randal Kleiser. The screenplay by Douglas Day Stewart was based on the novel The Blue Lagoon by Henry De Vere Stacpoole. The film stars Brooke Shields and Christopher Atkins...
. The director filmed part of the movie on a remote island and included shots of the native wildlife to enhance the feel of the movie, including a large colorful iguanid. Gibbons, who had been studying the Fiji banded iguana at the time, travelled to the island and identified it as a distinct species.
Distribution and habitat
The species is restricted to dry forest habitats, which is one of the most threatened vegetation types in the Pacific. It was once known from 14 islands in the western part of Fiji; however, recent surveys in the past two years have only confirmed the species on three islands: Yadua TabaYadua Taba
Yadua Tabu is a volcanic islet in Fiji, an outlier to the northern island of Vanua Levu, and immediately south of the larger island Yadua. Yadua Tabu covers an area of 0.7 square kilometres and has a maximum altitude of 100 meters...
, Monuriki
Monuriki
Monuriki is an uninhabited tiny island in the Pacific Ocean, off the coast of Viti Levu in a group of islands known as the Mamanuca Islands. The island is of volcanic origin and is approximately 1 kilometre long and 600 metres wide. The land area is approximately 0.4 square kilometres surrounded on...
, and Macuata
Macuata
Macuata is one of Fiji's fourteen Provinces, and one of three based principally on the northern island of Vanua Levu, occupying the north-eastern 40 percent of the island. It has a land area of 2004 square kilometers....
. Yadua Taba holds the highest concentration of the species, containing approximately 98% of all individuals, which is estimated to be 6,000 animals. This is the only legally protected population, as Yadua Taba is a National Trust of Fiji reserve and lacks the feral
Feral
A feral organism is one that has changed from being domesticated to being wild or untamed. In the case of plants it is a movement from cultivated to uncultivated or controlled to volunteer. The introduction of feral animals or plants to their non-native regions, like any introduced species, may...
goat
Goat
The domestic goat is a subspecies of goat domesticated from the wild goat of southwest Asia and Eastern Europe. The goat is a member of the Bovidae family and is closely related to the sheep as both are in the goat-antelope subfamily Caprinae. There are over three hundred distinct breeds of...
s which have destroyed the lizard's habitat on other islands.
Description
When Fiji crested iguanas first hatch from their egg
Egg (biology)
An egg is an organic vessel in which an embryo first begins to develop. In most birds, reptiles, insects, molluscs, fish, and monotremes, an egg is the zygote, resulting from fertilization of the ovum, which is expelled from the body and permitted to develop outside the body until the developing...
s they are dark green, but after several hours their skin becomes bright emerald green and narrow white bands can be seen along their body.
Their eyes are reddish orange or pinkish gold in color.
Diet
Fiji crested iguanas are herbivorous feeding on the leaves, fruit, and flowers of trees and shrubs, particularly hibiscus flowers of the Vau tree (Hibiscus tiliaceus). Captive hatchlings have been observed eating insects; however, adults will not.Reproduction
The breeding season occurs during the months of March and April, with courtship and mating commencing in January. The Fiji crested iguana is oviparous and has one of the longest incubation periods of any reptile at 189 days. Females guard the nest of four to six eggs, which is unusual for iguanids. Hatchlings emerge from their eggs in the rainy season and obtain moisture by licking wet leaves.Folklore
The Fijian name for iguana is "vokai", although some tribes call it "saumuri". Two tribes regard the iguana as their totemTotem
A totem is a stipulated ancestor of a group of people, such as a family, clan, group, lineage, or tribe.Totems support larger groups than the individual person. In kinship and descent, if the apical ancestor of a clan is nonhuman, it is called a totem...
and as such its name is not allowed to be mentioned in the presence of women or the offender may be beaten with a stick. The majority of Fijians, however, are terrified of the crested iguana because of its behavior when threatened.
Threats
The biggest threat this iguana faces is habitat loss due to fires, storms, agricultural development, and competition from feral goats. Goats were introduced to Yadua Taba in 1972 and numbered over 200 by the late 1970s. The vegetation on the island during this time was severely depleted by a combination of grazing and fires used to drive goats for ease of capture. After the discovery of the Fiji crested iguana, the island was declared a sanctuary and all but a few goats were removed and fires banned. As a result, the dry forest on the island has recovered to a great extent and is the best remaining example of dry forest Pacific. Invasive Leucaena treeLeucaena
Leucaena is a genus of flowering plants in the subfamily Mimosoideae of the legume family Fabaceae. It contains about 24 species of trees and shrubs, which are commonly known as Leadtrees. They are native to the Americas, ranging from Texas in the United States south to Peru...
s threaten the regeneration of native food trees for the iguanas, but the government of Fiji has taken steps to eradicate the trees.
A secondary threat is introduced predators in the forms of rat
Rat
Rats are various medium-sized, long-tailed rodents of the superfamily Muroidea. "True rats" are members of the genus Rattus, the most important of which to humans are the black rat, Rattus rattus, and the brown rat, Rattus norvegicus...
s, mongoose
Mongoose
Mongoose are a family of 33 living species of small carnivorans from southern Eurasia and mainland Africa. Four additional species from Madagascar in the subfamily Galidiinae, which were previously classified in this family, are also referred to as "mongooses" or "mongoose-like"...
s, and cat
Cat
The cat , also known as the domestic cat or housecat to distinguish it from other felids and felines, is a small, usually furry, domesticated, carnivorous mammal that is valued by humans for its companionship and for its ability to hunt vermin and household pests...
s which prey on the iguanas and their eggs. Additionally the iguana has been hunted as a food source and for the illegal animal trade.
In 2002, five adult iguanas were stolen from the sanctuary, but Fiji Custom officers caught the smuggler before he boarded his international flight. Since this incident, tourist visits to the sanctuary have been prohibited and only researchers are permitted to visit the island. In order to protect iguanas in the sanctuary from diseases and parasites, it is not permitted to return to the island any lizard that has been removed.