Komodo Dragons - Varanus Komodoensis

The Komodo dragon (Varanus komodoensis) is a species of lizard that inhabits the islands of Komodo, Rinca, Flores, and Gili Motang in Indonesia.  A member of the monitor lizard family (Varanidae), it is the largest living species of lizard, growing to an average length of 2 to 3 metres (6.6 to 9.8 ft) and weighing around 70 kilograms (150 lb). Their unusual size is attributed to island gigantism, since there are no other carnivorous animals to fill the niche on the islands where they live, and also to the Komodo dragon's low metabolic rate.  As a result of their size, these lizards dominate the ecosystems in which they live. Although Komodo dragons eat mostly carrion, they will also hunt and ambush prey including invertebrates, birds, and mammals.

Mating begins between May and August, and the eggs are laid in September. About twenty eggs are deposited in abandoned megapode nests and incubated for seven to eight months, hatching in April, when insects are most plentiful. Young Komodo dragons are vulnerable and therefore dwell in trees, safe from predators and cannibalistic adults. They take around three to five years to mature, and may live as long as fifty years. They are among the rare vertebrates capable of parthenogenesis, in which females may lay viable eggs if males are absent.

Komodo Dragon
Varanus komodoensis
Kingdom: Animalia      
Phylum:  Chordata
Class:  Reptilia
Order: Squamata
Family: Varanidae
Genus: Varanus
Species: V. komodoensis

Komodo dragons were discovered by Western scientists in 1910. Their large size and fearsome reputation make them popular zoo exhibits. In the wild their range has contracted due to human activities and they are listed as vulnerable by the IUCN. They are protected under Indonesian law, and a national park, Komodo National Park, was founded to aid protection efforts.

Population and Location
Komodo dragons are the world’s largest lizards. They can be found on only four islands – Komodo, Rinca, Gili Motang and Nusa Kode - in Komodo National Park, and a handful of small areas of northern and western Flores, just outside the Park. Less than 2500 of these giant lizards inhabit the Park’s dramatic landscape, and they do not exist anywhere else on earth. Komodo dragons, which were discovered by western science in 1910, are thought to have once lived over a much larger area. Growing pressure from human activities has reduced their habitats to the small refuges found today. Due to their extremely limited range, the Komodo dragon is considered to be endangered and in need of protection.

Origins
A member of the monitor family, the Komodo dragon is one of the oldest living lizards, thought to have originated 50 million years ago in either Asia or Australia. There are varying theories as to how it found its way to the Indonesian archipelago. Some scientists believe that dragons crossed from Australia to Southeast Asia around 15 million years ago, when the two continents collided, forming the highlands of New Guinea. Periods of low sea level would have allowed the dragons’ ancestors to migrate westward. Komodo dragons are thought to have differentiated from their Varanus ancestors around four million years ago, extending their range into the eastern islands of Indonesia. Changing sea levels associated with ice ages could have isolated them in their present location.

Size
Komodo dragons owe their outsize proportions to the fact that there are no other large predators to compete with in the isolated area in which they occur. The phenomenon is known as island gigantism. The largest recorded specimen was an impressive 3.13 meters (10 feet 2 inches) in length; large dragons usually weigh up to 90 kg (198 pounds). The largest Komodo dragon ever measured weighed 165.9 kilograms (365 pounds), including undigested food. Female Komodo dragons rarely grow over 2.5 meters (7 feet 6 inches) in length. Scientists believe that Komodo dragons can live up to 50 years, maybe longer.

Reproduction
Female Komodo dragons start mating when they are seven years old, males when they are eight. The mating season is generally from July to August, although mating behaviors have been observed during other months as well, usually during the dry season. Females lay 15 to 30 eggs at a time. The average number of eggs is about 18 per clutch, with one clutch per year. The dragons often lay their eggs in a burrow, sometimes using the ready-made mounds of the megapode (scrub fowl) as added protection. The female digs several false tunnels so that predators cannot easily find her eggs. The eggs incubate for eight to nine months, though the mother only guards them for a total of about three months. The eggs are about the size of swan eggs and have soft and leathery shells. They usually hatch in March or April.

Juveniles
On average, a newborn dragon is just 30.4 cm in length, though this can vary from 28 cm to 55 cm. The average weight is just 80.3 grams. Young dragons look very similar to small monitor lizards. They have yellow spots and dark markings on their bodies that eventually disappear as they grow older. Young dragons that are up to two years of age spend most of their time in trees to protect themselves from being eaten by larger dragons or other predators such as wild boar. The markings make excellent camouflage against tree trunks and leaves, for young dragons must fend for themselves after they are born. Young dragons usually eat other small lizards, eggs, rats, snakes, and insects that live in trees, stumps and logs.

Senses
Komodo dragons can see well (around 300 metres in daylight) and have reasonably good hearing too, but they rely mostly on smell. They use their tongue to detect scents and smells by picking up chemical particles in the air and ground, and then putting them in their Jacobson's organ, a kind of “super nose” located on the roof of their mouth. Dragons can detect specific scents up to five kilometers away. However, they can smell up to 11km away depending on the direction of the wind.

Diet & Hunting
Komodo dragons are carnivorous and not very particular about their meat. The adults mainly prey on deer and wild boar and sometimes other Komodo dragons. If they can, they will hunt water buffalo, palm civets, rats, and birds. They will also eat domestic animals like dogs, chickens and goats. Occasionally they will eat snakes, sea turtle eggs and monkeys. Komodo dragons prefer to eat animals that are already dead (carrion). They reject all plant matter, strictly eating meat in any form. When roused, Komodo dragons can run up to 18 km/h for short bursts, though usually they run at a slower pace of 8-10km/h. Dragons can swim at least 500 metres, but become sluggish in the water because their body temperature cools down.

When hunting, Komodo dragons usually attack sleeping animals or wait in ambush. If they cannot kill prey immediately, they will try to bite the animal on the leg or on the throat. Later, they will follow and wait for the animal to weaken and die before they eat it. Komodo dragon's saliva is not poisonous, but it is highly septic. There are over 60 types of bacteria in the dragon's saliva and at least one of them can cause septicemia. After being bitten, the prey can take a day to a couple of weeks to die from blood poisoning.

Dragons have small, sharp, curved teeth for grasping and ripping - they can eat up to 80 percent of their own body weight at one time. Researchers have witnessed a 42 kg dragon eat a 30 kg boar in just 17 minutes. Dragons eat almost everything, leaving behind only 8-13% of the carcass. Dragons eat whenever there is an opportunity - if there is no prey, they will scavenge and they usually eat or kill about once a month. They can, however, go without eating for several weeks.

The droppings of a Komodo dragon are white due to the presence of uric acid. All reptiles and birds have this in their droppings as well. Their droppings usually contain no water since the dragon’s body will try and conserve all water in their body, especially during the dry season when water is scarce.  Dragons need to drink water, but not often. They drink a lot when it is available, but this is very little in the dry season from April to November. Dragons can get 70% of their water requirement from their prey.

People and dragons
Komodo dragons have no natural predators, but deer poachers are their biggest threat. Timor deer are an essential part of the dragon’s diet and the prey/predator balance is critical for the Komodo dragon to survive. Dragons are thought to have attacked at least ten people and eaten one in the 1970's. The Komodo dragons are no longer fed as it was felt that they were relying too heavily on humans and diverging from their natural patterns of behaviour.
 

Habitat/Place to See Komodo Dragons

KOMODO ISLAND

Komodo is one of the 17,508 islands that make up the Republic of Indonesia. The island has a surface area of 390 km² and over 2000 inhabitants. The inhabitants of the island are descendants of former convicts who were exiled to the island and who have mixed themselves with the Bugis from Sulawesi. The population are primarily adherents of Islam but there are also Christian and Hindu minorities.
 

Komodo is part of the Lesser Sunda chain of islands and forms part of the Komodo National Park. Particularly notable here is the native Komodo dragon. In addition, the island is a popular destination for diving. Administratively, it is part of the East Nusa Tenggara province.

RINCA ISLAND

Rincah, also known as Rinca, is a small island near Komodo island, East Nusa Tenggara, Indonesia. The island is famous for komodo dragons, giant lizards that can measure up to three meters (ten feet) long. Rincah is also populated with many other species such as wild pigs, buffalos and many birds.
 

Being less known and less visited than Komodo it is an excellent place to see the Komodo Dragon in its natural environment with fewer people to disturb them. Day trips can be arranged from Labuanbajo on Flores by small boat. Visitors should check in at the park headquarters.
The island's area is 198 km2.[1]

In June 2008, five scuba divers (three British, one French and one Swedish) were found on the Southern coast of Rincah after having been missing for 2 days. The group had drifted 20 miles (32 km) from where their dive boat abandoned them. They survived on shellfish and oysters.[

GILI MOTANG

Gili Motang is a small island in Eastern Indonesia. It is part of the Lesser Sunda Islands chain, which together with the Greater Sunda Islands to the west make up the Sunda Islands.

The island, volcanic in origin, is approximately 30 km² (12 mi²) in area.

Home to a small population of about 100 Komodo Dragons, Gili Motang is part of Komodo National Park. In 1991 as part of the national park, Gili Motang was accepted as a UNESCO World Heritage Site.

Source: www.gokomodo.org