Text and photos by Mary L. Peachin
April/May 2012, Vol. 16. No 5
Biting to kill, once the Komodo, the world’s largest monitor lizard, gets a taste of blood, it is impossible to separate it from its prey. Its toxic saliva produces a deadly bacterial infection, one that that slowly kills larger animals. Once the animal dies, even the hide will be devoured. They have no predators.
Komodos congregate while feeding or mating. Otherwise, they tend to fight with one another and cannibalize the young, weak and old. Hatchlings, to avoid being eaten, live in trees for two years.
The toxic saliva that kills other animals does not affect the Komodo. Older lizards often die from starvation.
Researchers have recently discovered that, like snakes, Komodo’s also have venom that interacts with the saliva bacteria.
In Komodo National Park, Indonesia, an estimated 2,500 dragons live on five of the Park’s islands. They swim, propelled by their long tail, to inhabited islands.
By sunning in the daylight, they reach their optimal temperature. This provides them with energy to hunt. They can smell prey as far as seven miles away. Close to ten feet in length, they weigh as much as 150 pounds.
Females lay up to eighteen eggs which incubate for ten months. Mating begins between May and August, and eggs are laid in September. About twenty eggs are deposited in abandoned or self-dug nests. The eggs are incubated for seven to eight months, hatching in April, a time when insects are most plentiful. Young Komodo dragons are vulnerable and therefore dwell in trees, safe from other predators and cannibalistic adults. They take about eight to nine years to mature, and are estimated to live for up to thirty years.
Komodo’s arid, hilly island provides scenic views. Two rangers, carrying forked sticks, led us for an hour and a half hike. We sighted most of the dragons hanging out near the ranger station.
As we climbed from the visitor center on Loh Liang to a hill overlooking the bay, we could see our dive liveaboard boat The Arenui in the distant bay. We also saw the dragon’s prey, water buffalo and Timor deer. Several times we sighted Komodos along the trail, one drinking from a stream.
Locally, the Komodos are called “Ora.” Their population has increased to 1,100 on Komodo Island with about half of them living on nearby Rinca Island. They are considered the most famous indigenous species found in Indonesia 17,000 island archipelago.
Komodo National Park 1,817 square kilometers (0.7 square miles) includes the islands of Komodo, Rinca, Padar, Gili Motang along with several small islands in Sapa Strait located between Flores and Sambawa.
Recent research suggests that the size of the Komodo dragons may be descendants of an extinct prehistoric Pleistocene population of carnivorous varanid lizards that once inhabited Indonesia and Australia. Similar Australia fossil discoveries of V. komodoensis have been found dating back about four million years ago. Their size allowed them to dominate ecosystems.
In 1910, Western scientists first recorded Komodo dragons. Their large size and fearsome reputation made them popular zoo exhibits, but their were susceptible to disease and do not live well in captivity. In the wild, their range has been limited by human activity. They are now under the protection of Indonesian law, which create Komodo National Park.
The Komodo dragon prefers hot and dry places, and is typically found in dry open grassland, savanna, or low elevation tropical forest. They are primarily active during the day, although some nocturnal activity has been recorded. They are capable of running rapidly in brief sprints up to twelve miles per hour (20 k). They can dive to depths of fifteen feet, ( 4.5 m). Young dragons, because of their strong claws, are proficient at climbing trees. In order to reach prey, they are capable of standing on its hind legs, while using their tail as support. Mature dragons use their claws as weapons, their size makes climbing impractical.
For shelter, the Komodo dragon digs holes that measure three to ten feet ( 1–3 m) using their powerful front legs and claws. Their habit of sleeping in these burrows allows them to conserve body heat throughout the night thus minimizing basking time. Hunting in early afternoon, they spend the hottest part of the day in the shade. Resting places, usually located on ridges cleared of vegetation and offering a cool sea breeze, are marked with droppings. The ridges serve as a great place to ambush prey.
While Komodos prefer the ease of eating carrion, when ambushing prey, they make a stealthy approach. When the opportunity arises, the dragon will suddenly charge the underside or throat of the animal. They use their strong tails to knock down large pigs and deer.
Using their forelegs to hold the prey, they tear and swallow large chunks of flesh. Loosely articulated jaws, flexible skulls, and expandable stomachs allow the dragons to swallow prey, as large as a goat, in one gulp. But the process may take twenty minutes to complete. Komodos prefer to avoid vegetable contents in the stomach and intestines.
Red saliva lubricates the food. They have been observed trying to speed up the process by pushing a carcass against a tree to help force it down their throats. During the swallowing process, in order to avoid suffocating, the dragon breathes through a small tube, located under its tongue, which connects to its lungs.
After eating as much as 80 percent of its body weight, the dragon lazes in a sunny location to speed digestion. This is done to prevent undigested food from rotting or poisoning the dragon. Their slow metabolism allows them to survive with an average of twelve meals a year.
After digestion, the Komodo dragon regurgitates a gastric pellet, a mass of horns, hair, and teeth covered in a putrid mucus. It may then rub its face in the dirt or brush, an indication that it does not like its own mucus scent.
Similar to most animals in the wild, the largest eat first followed by size hierarchy. Larger males assert their dominance while smaller males submissively rumble hisses or use aggressive body language. Some of equal size may resort to wrestling.
Because Komodos are not capable of digesting bones, their excrement is mostly white. Their diet includes invertebrates, other reptiles, smaller Komodo dragons, birds and their eggs, small mammals, monkeys, wild boar, goats, deer, horses, and water buffalo. Younger dragons eat insects, eggs, geckos, and small mammals. They have been known to eat the occasional human. Their raiding of graves caused Komodo Island villagers to move gravesites from sandy to clay ground and pile rocks on top of them.
The Komodo drinks by using buccal pumping, the same a process used for respiration to suck in water. Lifting their head allows water to run down their throats.
As we walked among the dragons, I didn’t feel threatened, but always concerned. They appear to avoid encounters with humans and the younger ones scurried away. Older dragons are known to retreat from humans unless cornered. When threatened, they will hiss, and swing their tail. I have great respect for wild animals, and for sure, I wound never allow my presence to threaten them.