Komodo Dragon

## Description

The Komodo dragon (Varanus komodoensis) is a member of the monitor lizard family Varanidae that is endemic to the Indonesian islands of Komodo, Rinca, Flores, and Gili Motang. It is the largest extant species of lizard. As a result of their size, Komodo dragons are apex predators and dominate the ecosystems in which they live. Komodo dragons were first recorded by Western scientists in 1910. Their large size and fearsome reputation make them popular zoo exhibits.

## Appearance

Komodo dragons have a tail as long as their body and a long, yellow, deeply forked tongue. Their skin is usually gray in color reinforced by armored scales, which contain tiny bones called osteoderms that function as a sort of natural chain mail. This rugged hide makes Komodo dragon skin a poor source of leather. Additionally, these osteoderms become more extensive and variable in shape as the Komodo dragon ages, ossifying more extensively as the lizard grows. These osteoderms are absent in hatchlings and juveniles, indicating that the natural armor develops as a product of age and competition between adults for protection in combats over food and mates.

## Distribution

Komodo dragons are found in the Indonesian islands of Komodo, Rinca, Flores, and Gili Motang. These lizards prefer hot and dry places and typically live in dry, open grassland, savanna, and tropical forest at low elevations.

## Behavior

Komodo dragons are most active in the day, although they exhibit some nocturnal activity. They are solitary and come together only to breed and eat. These lizards are capable of running rapidly in brief sprints up to 20 km/h (12 mph), diving up to 4.5 m (15 ft), and climbing trees proficiently when young through use of their strong claws. To catch out-of-reach prey, Komodo dragons may stand on their hind legs and use their tail as a support. As they mature, their claws are used primarily as weapons, as their great size makes climbing impractical. For shelter, Komodo dragons dig holes with their powerful forelimbs and claws. These holes can measure from 1 to 3 m (3.3 to 9.8 ft) wide. Because of their large size and habit of sleeping in these burrows, these lizards are able to conserve body heat throughout the night and minimize their basking period the morning after. Komodo dragon hunt in the afternoon, but stay in the shade during the hottest part of the day. These special resting places, usually located on ridges with cool sea breezes, are marked with droppings and are cleared of vegetation. They serve as strategic locations from which Komodo dragons ambush deer.

## Venom

In late 2005, researchers at the University of Melbourne speculated the perentie (Varanus giganteus ), other species of monitors, and agamids may be somewhat venomous. The team believes the immediate effects of bites from these lizards were caused by mild envenomation. Bites on human digits by a lace monitor (V. varius ), a Komodo dragon, and a Spotted tree monitor (V. scalaris ) all produced similar effects: rapid swelling, localized disruption of blood clotting, and shooting pain up to the elbow, with some symptoms lasting for several hours.

## Diet

Komodo dragons are carnivores. Although they have been considered as eating mostly carrion, they will frequently ambush live prey. Their diet is wide-ranging and includes invertebrates, other reptiles (including smaller Komodo dragons), birds, bird eggs, small mammals, monkeys, wild boar, goats, deer, horses, and water buffalo. Young Komodos will eat insects, eggs, geckos, and small mammals, while adults prefer to hunt large mammals. Occasionally, they attack and bite humans.

## Reproduction

Komodo dragons exhibit a rare behavior for lizards; they may be monogamous and form "pair bonds". Mating occurs between May and August, with the eggs laid in September. During this period, males fight over females and territory by grappling with one another upon their hind legs, with the loser eventually being pinned to the ground. These males may vomit or defecate when preparing for the fight. The winner of the fight will then flick his long tongue at the female to gain information about her receptivity. Females are antagonistic and resist with their claws and teeth during the early phases of courtship. Other courtship displays include males rubbing their chins on the female, hard scratches to the back, and licking. Females lay their eggs from August to September and may use several types of the locality. They make many camouflage nests/holes to prevent other dragons from eating the eggs. Clutches contain an average of 20 eggs, which are incubated around 7-8 months. Hatching is an exhausting effort for the neonates, which break out of their eggshells with an egg tooth that falls off before long. After cutting themselves out, the hatchlings may lie in their eggshells for hours before starting to dig out of the nest. They are born quite defenseless and are vulnerable to predation. Young Komodos spend much of their first few years in trees, where they are relatively safe from predators. They become reproductively mature at 8-9 years of age.

## Population

### Threats

Volcanic activity, earthquakes, loss of habitat, fire, loss of prey due to poaching, tourism, and illegal poaching of the dragons themselves have all contributed to the vulnerable status of the Komodo dragon.

### Number

According to the Wikipedia resource, in 2015 the total population size of the Komodo dragon was 3,014 individuals. Currently, this species is classified as Vulnerable (Vu) on the IUCN Red List.

### Ecological niche

As a result of their size, Komodo dragons dominate the ecosystems in which they live. They are top predators and also scavengers. These lizards eat recently dead animals preventing the spread of disease and assist with a sort of “natural recycling”.

## Fun Facts

The Komodo dragon is also known as the Komodo monitor or the Komodo Island monitor in the scientific literature. To the natives of Komodo Island, it is referred to as ora, buaya darat (land crocodile), or biawak raksasa (giant monitor).

Komodo dragons can see objects as far away as 300 m (980 ft) and can distinguish colors.

Komodo dragons use their tongue to detect, taste, and smell stimuli with the vomeronasal sense using the Jacobson's organ, rather than using the nostrils. With the help of a favorable wind and their habit of swinging their head from side to side as they walk, Komodos can detect carrion from 4-9.5 km (2.5-5.9 mi) away.

Some of the scales on the skin of Komodos are reinforced with bone and have sensory plaques connected to nerves to facilitate their sense of touch. The scales around the ears, lips, chin, and soles of the feet may have three or more sensory plaques.

The eating habits of Komodo dragons follow a hierarchy, with the larger animals generally eating before the smaller ones. Dragons of equal size may resort to "wrestling." Losers usually retreat, though they have been known to be killed and eaten by victors.

The Komodo dragon drinks by sucking water into its mouth via buccal pumping, a process also used for respiration; the animal lifts its head and lets the water run down its throat.

Komodo dragons prefer to avoid encounters with humans. Juveniles are very shy and will flee quickly into a hideout if a human comes closer than about 100 meters (330 ft). Older animals will also retreat from humans from a shorter distance away. If cornered, they will react aggressively by gaping their mouth, hissing, and swinging their tail. If they are disturbed further, they may start an attack and bite.