Monitor, Komodo Island

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Monitor, Komodo Island

Varanus komodoensis

phylum: Chordata

class: Reptilia

order: Sauria

family: Varanidae

status: Vulnerable, IUCN Endangered, ESA

range: Indonesia

Description and biology

The Komodo Island monitor, also called the Komodo dragon or "ora" by the people of Komodo, is the largest living lizard on Earth. An average adult can measure up to 10 feet (3 meters) long and weigh 300 pounds (136 kilograms). Despite its size, it can move quickly on the ground and is an agile swimmer and climber. The monitor has a dark gray, stocky body and stout, powerful legs with sharply clawed feet. It has a large head and a long, forked tongue that it uses to "taste" the air, following the scent of its prey.

The monitor feeds on wild pigs, deer, water buffalo, dogs, goats, rats, snakes, birds, other monitors, and, if given the chance, humans. It attacks by ambushing its prey, lunging from the tall grass of its savanna habitat. The monitor has razor-sharp serrated teeth. One bite is often enough to subdue its prey. If the prey happens to escape, it usually will not live long. The mouth of a monitor is filled with poisonous

bacteria. The bite area becomes infected over the course of a few days, and the prey weakens to the point when it can no longer flee. The monitor then moves in and devours the prey completely—nothing is left. The monitor's yellow tongue and foul mouth odor (caused by the bacteria present) may have inspired legends of fire-breathing dragons.

After mating, female Komodo Island monitors lay 15 to 30 eggs with smooth, leatherlike shells in a hole. They usually lay eggs several times between July and early September. The eggs hatch after about 34 weeks. For the first year of their lives, young monitors live in trees and feed on insects. When they have grown to a length of about 3 feet (0.9 meter), they move to the ground. This helps protect them from predators, including adult monitors.

Habitat and current distribution

The Komodo Island monitor is found only on Komodo, Rintja, and western Flores Islands in Indonesia. Biologists (people who study living organisms) estimate the monitor's total population to be between 4,000 and 5,000.

Monitors prefer to inhabit dry savanna, woodland thickets, and forest fringes and clearings.

History and conservation measures

The Komodo Island monitor once occupied many Indonesian islands. It was discovered on Komodo Island in 1912. Since that time, its population has been drastically reduced—mainly by humans. The monitor has been hunted for sport, for collections, and for its hide. Although laws now limit commercial hunting, the monitor is still sometimes poisoned by villagers who believe it is a threat to children and domestic animals.

The over-hunting of deer by humans in the monitor's range has reduced its available prey. Its habitat also has been reduced by the burning and clearing of woodland to create farmland and villages. The monitor is further disturbed by hordes of tourists who travel to Komodo Island specifically to see the world's largest lizard. The Indonesian government is currently trying to regulate this "ecotourism."

A capitive-breeding program has not been successful in saving the Komodo Island monitors since they do not reproduce well in captivity. They often die from diseases and infections.