Iguana

  • CLASS: Reptilla (Reptiles)
  • ORDER: Squamata
  • FAMILY: Iguanidae
  • SUBFAMILY: Iguaninae
  • GENERA: 8
  • SPECIES: 35 currently recognized

LIFE SPAN

4 to 60 years, depending on species

YOUNG

Number of eggs laid: 5 to 40 per clutch, depending on species

Incubation period: 65 to 115 days, depending on species

Age of maturity: 3 years

SIZE

Length: Longest – green iguana Iguana iguana, 5 to 7 feet (1.5 to 2 meters) including tail; smallest – spiny-tailed iguana Ctenosaura sp., 4.9 to 39 inches (12.5 to 100 centimeters) including tail

Weight: Heaviest – blue iguana Cyclura lewisi, up to 30 pounds (14 kilograms)

Category:

guanas are some of the largest lizards found in the Americas, with their whiplike tail making up about half of that length. Like other reptiles, iguanas are cold-blooded, egg-laying animals with an excellent ability to adapt to their environment.

Iguana species vary greatly in size, color, behavior, and their endangered status in the wild. Some, like the green iguana, are quite common; others, like Fiji’s banded iguanas, are endangered. Iguanas native to San Diego County are the desert iguana and the chuckwalla.

HABITAT AND DIET

Galapagos marine iguana

Different iguana species look and act so differently, you might not recognize them as members of the same family. While some iguanas have colors that are vivid and bright, others have rather dull colors. Because iguanas can be found in a variety of habitats, each species has its own unique adaptations. The marine iguana of the Galápagos Islands is a skillful swimmer, and its black coloration helps it to warm its body after swimming in the cold ocean.

In contrast, the green iguana is at home high in the trees of a tropical rainforest, while still other iguanas have adaptations that allow them to live successfully in the dry, hot desert or rocky areas.

With an emerald green body and bands of white or blue, more prominent on the males, Fiji’s iguanas inhabit a multitude of habitats, from coastal swamps and lowland forests to rainforests on Fiji’s volcanic slopes. Highly arboreal, they have long toes with sharp claws and long tails for balance in the treetops. Rarely seen on the ground, banded iguanas move from tree to tree by using the overlapping branches. They are omnivorous, feeding on leaves, flowers, fruits, and small insects.

Adult banded iguanas may reach a length of 21 inches (53 centimeters)—more than half of which is the tail. When fully mature, they weigh between 3.5 and 7 ounces (99 to 199 grams), and males tend to be larger and heavier than females.

The Caribbean islands are rich in reptiles, with more than 500 reptile species, 94 percent of which are found nowhere else on Earth. Several Caribbean iguana species are known collectively as rock iguanas, and some are found on just one or two islands. Female rock iguanas lay a clutch of 5 to 20 relatively large eggs each year; the larger eggs result in large hatchlings that evolved in response to the lack of native predators. Unlike their mainland counterparts, such as green iguanas, the island-dwelling iguanas do not need to produce a lot of offspring as a hedge against predators.

The smallest of the rock iguana group are the Turks and Caicos iguanas. All eat a wide variety of fruits and serve as important seed dispersers for many native plants.

Most iguanas are herbivores, eating fruits, flower buds, and young leaves. Some also eat the occasional juicy mealworm or wax worm! The marine iguana dives in the ocean to scrape algae from rocks.

At the San Diego Zoo and San Diego Zoo Safari Park, our iguanas are offered a fruit salad that includes dark leafy greens and a variety of fruits, while some also receive crickets, mealworms, and wax worms. But because wax worms are high in fat, they are considered the “dessert” part of the menu!

Speaking of food, iguanas themselves are eaten by a variety of natural predators—hawks, owls, snakes—and humans. Green iguanas are bred and raised on farms in Central and South America to be eaten by people. Young iguanas are particularly vulnerable to predation by feral cats, and no iguana is safe from a pack of dogs. The iguana’s whiplike tail can be used for defense, and many species have tails with sharp “spines” that pack an extra “punch.”

FAMILY LIFE

Three endangered Grand Cayman blue iguana hatchlings
Three endangered Grand Cayman blue iguana hatchlings.

No mama for the baby iguana: The females of most iguana species dig a burrow in a sunny area, lay their eggs inside, cover them, and then leave the eggs alone. Even arboreal iguana species leave the trees to lay their eggs. The temperature in the burrow stays a fairly constant 77 to 89 degrees Fahrenheit (25 to 32 degrees Celsius). The warm temperature incubates the eggs. All eggs in a nest usually hatch at the same time, and the young dig out of the burrow without help from the parents. On their own, iguana hatchlings face many dangers.

AT THE ZOO

The San Diego Zoo and San Diego Zoo Safari Park are home to many types of iguanas. As we care for them, we learn important things about them, such as ideal conditions for reproducing or special dietary needs. The information we learn can help us to strengthen the chances of iguana survival in the wild. We’ve had many breeding success stories over the years: the San Diego Zoo was the first zoo in the US to hatch the critically endangered Anegada Island iguana.

The Zoo has a long history of working with Fiji Island banded iguanas, starting with a gift of six of these lizards from the prince of Tonga in 1965, and we welcomed our first hatchling in 1981. Today, the Zoo has the largest and most successful colony of this endangered species outside of Fiji.

Reviews

There are no reviews yet.

Be the first to review “Iguana”

Your email address will not be published. Required fields are marked *