Fortunately for the babies, the adults are too heavy and clumsy to climb trees. Youngsters live in the trees eating anything that fits into their mouth: eggs, grasshoppers, beetles, and geckos. However, their primary diet is the Tokay gecko, an aggressive lizard itself with an unmistakably loud call! The young dragons find them most often in the hollows of tree trunks where the geckos nest and shelter.
When they are about 4 years old and 4 feet long 1. The San Diego Zoo acquired its first two Komodo dragons in They were believed to be a "pair" male and female , but were too young when they arrived for us to be absolutely certain about that.
Named One Eye, that male arrived from the Basel Zoo in Switzerland in , but no offspring were ever produced. We planned to find an easy, safe way to determine the sex of Komodos at a young age. After nine months of blood sampling and ultrasound exams, we found that we could determine the sex of two-year-old dragons successfully. This knowledge is tremendously helpful for managed-care breeding programs.
The technique also proved successful in determining the sex of all our monitor lizards as well as Gila monsters and beaded lizards.
The Kenneth C. Griffin Komodo Kingdom at the Zoo opened in summer The magnificent Komodo dragon is endangered. One study estimated the population of Komodo dragons within Komodo National Park to be 2, Another study estimated between 3, and 3, individuals. On the much larger island of Flores, which is outside the National Park, the number of dragons has been estimated from to Komodo dragons that live outside of the National Park are at greatest risk, as habitat fragmentation and frequent burning of grasslands to hunt Timor deer are the greatest risks to their survival.
On the island of Flores, Komodo habitat is shrinking quickly because of the impact of a human population of approximately 2 million.
San Diego Zoo Wildlife Alliance participates in conservation research to help these carnivorous giants. We are learning about the population biology of Komodo dragons in Komodo National Park.
By studying Komodo dragon births, deaths, survival, and growth, we hope to learn many important things that will enable us to better conserve and manage them.
In addition, we are exploring how things such as prey availability and rainfall influence the biology of the different dragon populations across Komodo National Park. Before we started this project, many basic pieces of information that are needed to manage and conserve Komodo dragons were unknown, including how many Komodo dragons live on each island, how different the populations are among the islands, and if the dragons move much among islands. Over the years we have been able to provide answers to some of these questions.
For example, we now know that despite living across several islands, dragons only occasionally swim to other islands and thus seem to be homebodies.
Furthermore, Komodo dragons tend to remain within the same valleys they were hatched in. Similarly, females often nest in the same nest location each time. They also hunt and ambush prey such as invertebrates, mammals and birds. To catch prey that is out of reach, komodo dragons are able to stand on their hind legs and use their tails as support. They have also been known to use their tails to knock down large deer and pigs.
Komodo dragons eat by tearing large chunks of flesh and swallowing them whole while holding the carcass down with their forelegs.
Because of their slow metabolism, large dragons can survive on as little as 12 meals a year. Because the Komodo dragon does not have a diaphragm, it cannot suck water when drinking, nor can it lap water with its tongue. Instead, it drinks by taking a mouthful of water, lifting its head, and letting the water run down its throat.
A komodo dragon can eat a whopping 80 percent of its body weight in a single feeding. Komodo Dragons are mostly active during the day but have shown some nocturnal behaviour.
They are solitary animals that only come together to breed and eat. They are quite fast creatures and can move rapidly in brief sprints up to 20 kilometres per hour Young komodo dragons can climb trees easily with the use of their strong claws.
Because of their large size, Komodo Dragons are able to conserve body heat by sleeping in their burrows reducing their need to bask in the mornings. They typically hunt in the afternoons and stay in shaded areas during the hottest parts of the day.
Although not strictly venomous, the bite of a Komodo Dragon is not just dangerous for the physical damage the Komodo is capable of causing, it is also heavily dosed with dangerous bacteria.
If a victim is lucky enough to escape being eaten, because of the bacteria, it is likely to die eventually. A komodo dragon will follow its escapee until this happens usually within a week , and then consume it.
The Komodo Dragon breeding season occurs between May and August. Around 20 eggs are laid in September which are deposited in abandoned megapode nests Megapode — stocky, medium-large chicken-like birds with small heads and large feet.
This system, along with an undulatory walk, in which the head swings from side to side, helps the dragon sense the existence and direction of food. At times, these reptiles can smell carrion, or rotting flesh, up to 2. This lizard's large, curved and serrated teeth are its deadliest weapon, tearing flesh with efficiency.
The tooth serrations hold bits of meat from its most recent meal, and this protein-rich residue supports large numbers of bacteria. Some 50 different bacterial strains, at least seven of which are highly septic, have been found in the saliva. Researchers have also documented a venom gland in the dragon's lower jaw.
In addition to the harmful bacteria, the venom prevents the blood from clotting, which causes massive blood loss and induces shock. The Komodo's bite may be deadly, but not to another Komodo dragon. Those wounded while sparring with each other appear to be unaffected by the bacteria and venom.
Scientists are searching for antibodies in Komodo dragon blood that may be responsible. The lizard's throat and neck muscles allow it to rapidly swallow huge chunks of meat. Several movable joints, such as the intramandibular hinge, open its lower jaw unusually wide. The dragon's stomach also easily expands, enabling an adult to consume up to 80 percent of its own body weight in a single meal. When threatened, Komodo dragons can throw up the contents of their stomachs to lessen their weight in order to flee.
Komodo dragons are efficient eaters, leaving behind only about 12 percent of their prey. They eat bones, hooves and sections of hide, as well as intestines after swinging them to dislodge their contents. At the Smithsonian's National Zoo, the Komodo dragon eats rodents, chicks and rabbits. Occasionally, he consumes fish and carcass meals of beef. Because large Komodos cannibalize young ones, the young often roll in fecal material, thereby assuming a scent that the large dragons are programmed to avoid.
Young dragons also undergo rituals of appeasement, with the smaller lizards pacing around a feeding circle in a stately ritualized walk. Their tail is stuck straight out and they throw their body from side to side with exaggerated convulsions. Determining the sex of a Komodo dragon is challenging for researchers, as no obvious morphological differences distinguish males from females.
One subtle clue is a slight difference in the arrangement of scales just in front of the cloaca. Courtship opportunities arise when groups assemble around carrion to feed, and mating occurs between May and August. Dominant males compete for females in ritual combat. Using their tails for support, they wrestle in upright postures, grabbing each other with their forelegs as they attempt to throw the opponent to the ground. Blood is often drawn, and the loser either runs away or remains prone and motionless.
Females lay about 30 eggs in depressions dug on hill slopes or within the pilfered nests of megapodes — large, chicken-like birds that make nests of heaped earth mixed with twigs that may be as long as 3 feet 1 meter in height and 10 feet 3 meters across.
Delays in egg laying may occur, which could help the clutch avoid the brutally hot months of the dry season. Additionally, unfertilized eggs may have a second chance with subsequent mating. While the eggs incubate in the nest for about nine months, the female may lay on the nest to protect the eggs. No evidence of parental care for newly hatched Komodos exists. The hatchlings weigh less than 3. Their early years are precarious, and they often fall victim to predators, including other Komodo dragons.
At 5 years old, they weigh about 55 pounds 25 kilograms and average 6. At this time, they begin to hunt larger prey.
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