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Green iguana

The green iguana is a large, arboreal, and primarily herbivorous lizard native to Central and South America, and the Caribbean. Known for its distinctive dorsal spines, dewlap, and vibrant coloration that can vary by region, it is also a popular but demanding pet. This species plays a significant ecological role and has become notably invasive in various subtropical and tropical regions globally.

Key Facts

  • Grows up to 1.7 meters (5.6 ft) in length, with some individuals exceeding 2 meters.
  • Primarily herbivorous, feeding on leaves, flowers, and fruits.
  • Possesses a parietal eye (third eye) on its head, sensitive to light and movement.
  • Males are sexually dimorphic, with longer dorsal spines and more developed jowls.
  • Oviparous, with females laying clutches of 20 to 71 eggs annually.
  • Can be found in trees, near water, and also as skilled burrowers.
Green iguana
Scientific Name
Iguana iguana
Family
Iguanidae
Common Names

American Iguana, Common Green Iguana, Iguana

Geographic Distribution

Mexico, Brazil, Paraguay, Bolivia, Caribbean

Physical Description
  • Large Lizard, Likely the Largest In the Iguana Family.
  • Adults Typically 1.2 To 1.7 m In Total Length; Tail Comprises Much of This Length.
  • Snout-To-Vent Length of Most Green Iguanas Is 30 To 42 cm .
  • Typical Adult Male Weighs Around 4 kg ; Females Typically Weigh 1.2 To 3 kg .
  • Large Males Can Exceed 8 kg and 2 m In Length.
  • Possess A Row of Spines Along Their Backs and Tails.
  • Have A Well-Developed Dewlap Used For Thermoregulation and Display.
  • Sharp, Leaf-Shaped Teeth With Serrations, Capable of Shredding Leaves.
  • Coloration Varies Regionally: Bluish In Southern Areas, Green To Lavender, Black, Or Reddish-Brown On Islands, Red In Western Costa Rica, Orange In Northern Ranges, Bright Blue In Juveniles From El Salvador, Yellow Or Orange In Southeastern Florida.
  • Some Populations, Particularly From Guatemala and Southern Mexico, May Have Small Horns On Their Snouts.
  • Possess A Parietal Eye On the Top of Their Head, Sensitive To Light and Movement.
Diet

Leaves, Flowers, Fruit, Growing Shoots, Grasshoppers, Tree Snails, Birds' Eggs, Chicks, Carrion, Invertebrates, Human Garbage, Poultry Feces

Lifespan Years
Not specified in text
Behavioral Traits
  • Diurnal
  • Arboreal
  • Agile Climbers, Can Fall Significant Distances and Land Unhurt.
  • Often Found Near Water.
  • Skilled Burrowers, Creating Burrows Up To 2.4 Meters Deep.
  • Propel Themselves Through Water With Powerful Tail Strokes.
  • When Frightened, Attempt To Flee and Dive Into Water If Available.
  • When Cornered, Display Dewlap, Puff Up Body, Hiss, and Bob Head.
  • Can Lash With Tail, Bite, and Use Claws Defensively When Threatened.
  • Use 'Head Bobs' and Dewlaps For Social Interactions, Greetings, and Courtship.
  • Juveniles Stay In Familial Groups For the First Year.
  • Males May Shield and Protect Females From Predators Within Familial Groups.
Diet Category
Predators

Various Vertebrate Species, Amphibians, Other Green Iguanas

Threats

Habitat Loss, Pet Trade, Climate Change, Competition With Native Species, Spread of Salmonella

Gestation Incubation Period Days
70-105

About Green iguana

The Green Iguana

The green iguana (Iguana iguana), also known as the American iguana or the common green iguana, is a large, arboreal, and predominantly herbivorous lizard belonging to the genus Iguana. Native to a vast range from southern Brazil and Paraguay northward to Mexico and across the Caribbean, this species is easily recognized by its prominent dorsal spines and a dewlap beneath its throat. While usually green, its coloration can vary significantly by region, exhibiting shades of blue, red, orange, or brown.

Physical Characteristics and Adaptations

Adult green iguanas typically reach lengths of 1.2 to 1.7 meters (3.9 to 5.6 ft), with some males growing over 2 meters (6.6 ft). They possess sharp, serrated teeth adapted for shredding plant matter. A unique feature is the parietal eye, or 'third eye', on their head, which helps detect light changes and movement, aiding in predator avoidance from above. Their whip-like tails can be used as a defense mechanism, and they can detach their tails to escape predators, with regeneration occurring over time.

Habitat and Behavior

Green iguanas are diurnal and arboreal, commonly found in trees near bodies of water. They are agile climbers, capable of surviving falls from significant heights. They are also skilled burrowers, creating tunnels for shelter. Socially, they use head bobs and dewlap displays for communication, courtship, and territorial interactions. While primarily herbivores, wild iguanas may opportunistically consume small invertebrates, eggs, or carrion. Females lay clutches of 20 to 71 eggs annually, with no parental care provided after egg-laying.

Distribution and Invasive Status

Beyond their native range, green iguanas have become highly invasive in many subtropical and tropical regions worldwide, including parts of the United States (Florida, Texas, Hawaii), the Caribbean, and Fiji. Their introduction, often through the pet trade, has led to ecological concerns, including competition with native species and the potential spread of diseases like Salmonella. In some areas, their populations are so significant that eradication efforts have been proposed.

Source: Wikipedia ↗

Frequently Asked Questions

What is the native range of the green iguana?

The native range of the green iguana extends from southern Mexico to central Brazil, Paraguay, and Bolivia, as well as various Caribbean islands including Grenada, Aruba, Curaçao, Bonaire, Trinidad and Tobago, St. Lucia, St. Vincent, Montserrat, Saba, and Útila.

What do green iguanas eat?

Green iguanas are primarily herbivores, feeding on a wide variety of leaves, flowers, fruits, and growing shoots. While wild adults have occasionally been observed eating birds' eggs, chicks, carrion, or small invertebrates, their diet is predominantly plant-based.

Are green iguanas venomous?

No, green iguanas are not venomous. They possess sharp teeth capable of shredding plants and can inflict bites if threatened, but they do not possess venom glands.

How large can a green iguana get?

Adult green iguanas typically grow to between 1.2 to 1.7 meters (3.9 to 5.6 ft) in length from head to tail. Some large males can reach or exceed 2 meters (6.6 ft) in length and weigh over 9 kg (20 lb).

What is the 'third eye' on a green iguana?

Green iguanas have a parietal eye, also known as a third eye or pineal eye, on the top of their head. This organ is sensitive to light and dark changes and can detect movement, helping the iguana to sense predators from above.

Why are green iguanas considered invasive in some areas?

Green iguanas have been introduced to many subtropical and tropical environments outside their native range, often through the pet trade or accidental dispersal. Once established, they can reproduce rapidly and compete with native species for resources, posing a threat to local ecosystems.

What are the main physical characteristics of a green iguana?

Green iguanas are characterized by a row of spines along their backs and tails, a well-developed dewlap under their neck used for thermoregulation and display, and sharp, serrated teeth. Their coloration can vary significantly by region, ranging from green to blue, red, orange, or brown.