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Department of Pla nninii and Natu ial Resources
Division of Fish and Wildlife
U.S.V.I. Animal Fact Sheet #08
* Size Largest of the islands lizards
* Color Juveniles Bright emerald green
* Adults Green and dark stripes
* Spines Run the length of the body
* Cheek Scale Large and Green
The name iguana is derived from the Spanish
equivalent to the Carib Indian name "iwana". The
green iguana is a reptile and is cold blooded. This
means that the animals do not create or maintain
their own body heat. To warm up they must find an
area that is warm or to bask in the sun to warm up
Iguanas are lizards in which the eyes are the
predominant sense organs. Their eyes have well
developed eyelids and round pupils. Their tongues
are short and thick with a slight fork at the tip.
They have spines running from the back of their
head to the tail tip.
Reptiles have one advantage over birds and
mammals, at least in the Caribbean. They do not
need to maintain a constant body temperature and
therefore need less food. As a result they can
survive in habitats such as the dry east end of St.
Thomas and St. Croix, where food is limited.
The most obvious feature of iguanas is their dry
scale covered skin. This covering of scales reduces
water loss and may facilitate the uptake of solar
energy. Certain scales have been modified into
spines along the head and backbone, which can
dissuade attackers. They also have dewlaps (throat
fans) as well as fringes on the toes that are used for
display. Their limbs are well developed and they are
Juveniles are born with brightly colored green
skin, which helps them to hide amongst the leaves
of tropical trees. As the iguana ages, the color fades
to an aged brown, grey and black color.
Distribution & Habitat
Iguanas are found throughout tropical and sub-
tropical regions of the world. Green iguanas are
found throughout the Americas. The species found
in the U.S. Virgin Islands is the Green Iguana,
(Iguana iguana). The Ground Iguana, Cyclura
pinguis, is found in Puerto Rico as well as Anegada
but has not been found in the rest of the VI.
It is possible that the green iguana is not native to
the Virgin Islands. One hypothesis is that
Precolumbian Indians exterminated the ground
iguana (Cyclura) hunting them for food and
introduced the green iguana from South America to
replace them as a food source. Iguanas are
considered to be indigenous animals by the
Department of Planning and Natural Resources.
Iguanas occupy both xeric habitats (any habitat
with little rainfall), and in mesic habitat (habitat
with plentiful rainfall and well drained soils). In the
USVI green iguanas they are found throughout the
islands, in Acacia thickets, along mangrove edges,
on cemetery walls. Iguanas are diurnal (they are
active in the day). They spend their time
thermoregulating (maintaining heir body
temperature by moving from sun to shade and back
again) and foraging on bushes, trees, on open rocky
ground, cliff faces, and rocky crevices. Juveniles
sleep in low trees and bushes, adults probably sleep
in large trees, in rock piles; rock crevices; or in
Iguanas are herbivores, meaning that their diet is
primarily comprised of plants, fruits and seeds.
Iguanas consume a great variety of plant materials,
although they mainly feed on leaves and fruits,
especially as adults. As juveniles their diet may
include insects as well as plants. This is not
unusual, many species of lizards will shift their
diets with maturity and seasonal changes in the
availability of food.
In most reptiles there is sexual dimorphism (the
two sexes differ in adult size, shape or color). The
males of many lizards are bigger than the females.
The difference between the sexes are particularly
striking among the iguanid families. Males tend to
be more brightly colored, especially in the breeding
season, and in some species they possess erectile
crests and throat fans which play a role in courtship
and territorial displays.
All reptiles practice internal fertilization, the
sperm being introduced directly into the female's
cloaca, the common opening, which transmits eggs
or sperm and excretory products.
Male iguanas and other lizards have evolved
paired organs called hemipenes, which are used to
fertilize the females. Only one hemipene is used at
Breeding is greatly influenced by environmental
factors such as temperature and the duration of
daylight. In the VI, iguanas breed in late January to
early March. During this time we see iguanas
scurrying across our roads.
Most lizards exhibit little maternal care, except
for finding and excavating a suitable site for egg
laying. A female typically lays her eggs beneath a
log or beneath a rock where humidity is relatively
high. The green iguana will lay as many as 45 eggs
in one clutch. Iguanas lay eggs, which are resistant
to drying out. These eggs possess a shell, which
may be pliable or parchment-like in texture. The
incubation period is long compared to other lizards,
about three months. Hatching from the egg is
facilitated by the presence of a sharp, forward
pointing egg tooth, which is later shed.
What you can do to HELP
+ DO NOT FEED IGUANAS!! Iguanas are
attracted to food and become very abundant if
fed. They will also loose their natural fear of
humans and become aggressive. At restaurants
they may jump on patrons and bite or scratch
them. They may also try to steal food from
+ Reducing the amount of pesticides and
chemicals we use to control pests will help our
+ Remember it is illegal to take, catch, possess,
injure, harass, or kill any indigenous species.
The only exceptions are for people holding valid
permits from the Division of Fish and Wildlife.
+ Report poachers to your local Environmental
Enforcement office, or dial 911.
+ For more information on this and other animals
in the Virgin Islands please visit out website at:
Written by William Coles 2002.
THIS PUBLICATION WAS PRODUCED WITH
FUNDS FROM THE WILDLIFE
CONSERVATION AND RESTORATION
FOR MORE INFORMATION ON
OUR NATIVE ANIMALS CONTACT
DIVISION OF FISH AND WILDLIFE
6291 ESTATE NAZARETH, 101,
ST. THMAS, VI 00802
PHONE 340-775-6762 FAX 340-775-3972
45 MARS HILL, ST. CROIX, VI 00840
PHONE 340-772-1955 FAX 340-772-3227