Dragon Doings

October 1993

Number 1

14 MORE KOMODO DRAGONS !!!

After a 216 day wait, the first of 1993's Komodo dragons emerged from its egg on August 23 at the Reptile House of the National Zoo (NZP). Over the next month, seventeen dragons hatched out of the twenty-four eggs laid this past January 19 at the Cincinnati Zoo where the NZP female dragon had been sent on a breeding loan in late 1992. After recovery from a nest the female had dug two feet down into the ground, the eggs were brought back to NZP for incubation. As in 1992, some of the eggs were incubated at George Mason University (Fairfax, Virginia) and some at NZP to avoid "having all the eggs in one basket."

Currently fourteen hatchlings survive. The other three died from unknown causes within a couple of weeks of hatching. This survival rate of 58% improves upon last year's rate of 50%, but there is still much to be learned about the optimal incubating conditions for Komodo dragon eggs.

More may be learned in the months to come. Unexpectedly, the female bred a second time with the same Cincinnati male in June and laid another twenty-six eggs. Of those, twenty-one eggs appear to be viable and are currently being incubated at the Cincinnati Zoo. They are expected to hatch sometime in February 1994.

"Herpetological event of the millennium"

Whether it's called "the zoo event of the decade" (Dale Marcellini, Curator of Herpetology) or "the herpetological event of the millennium" (Michael Robinson, National Zoo Director), the successful breeding of Komodo dragons in 1992 and again in 1993 is a significant event for the future of Komodo dragons in captivity and in the wild. It represents the first time that Komodo dragons have been successfully bred outside of Indonesia--an achievement that was recognized by the American Association of Zoological Parks and Aquariums which awarded NZP with the Edward H. Bean Award for most significant animal husbandry event in 1992.

While the exact number of Komodo dragons in the wild is not known, scientists estimate there are 2000 to 5000. In captivity, there are almost certainly no more than thirty adult dragons in the entire world. So between the two dragon hatchings here at NZP, the captive population has been doubled in the past year!

What's happened to the 1992 hatchlings?

Over the summer, homes were found for nine of the thirteen dragons hatched last year. While a number of zoos requested dragons, they were only offered to institutions meeting a number of predetermined criteria. A primary requirement was the ability to appropriately house and care for the dragons. Special emphasis was placed on the dragons having access to sunlight; generally exposure to ultraviolet radiation is important to lizards for proper synthesis of vitamin D3. A second criterion was a willingness and a commitment by the institution and its staff to work closely with NZP on future Komodo dragon research studies. To this end, a Komodo Dragon Trust Fund, administered by the Smithsonian Institution and funded by participating zoos, has been established to support both field research in Indonesia and captive breeding programs in zoos.

As of October 1, dragons have found new homes at Zoo Atlanta, Audubon Zoo in New Orleans, Honolulu Zoo, Rio Grande Zoo in Albuquerque, Fort Worth Zoo, and St. Louis Zoo. Homes have not yet been found for another one or two dragons. Two or three will remain at NZP.

As for the newly hatched dragons, the conditions of the breeding loan stipulate that NZP and Cincinnati Zoo will each receive half the hatchlings. Of the seven that NZP will keep from this clutch, it is not yet decided how many will actually stay here and how many will be placed elsewhere.

Mama dragon returns home

On October 13 the female dragon returned home from the Cincinnati Zoo. The breeding loan had been arranged with the Cincinnati Zoo because they have the only other Komodo dragons in the United States--two males. By breeding the female with one of their males rather than with the NZP male a second time, the diversity of the gene pool represented by the captive population in the United States was increased. (The other male has since been on loan to the San Diego Zoo in order to make room for the NZP female.)

Mama dragon currently is in a holding area in the Reptile House basement. Once repairs to the outdoor Komodo dragon enclosure (behind the Reptile House) are completed (hopefully by the end of October), she will be moved into the exhibit with the male. Be sure to stop by and see her then.

Endangered in Indonesia

While the future of Komodo dragons in captivity seems brighter, they remain an endangered species. To some people, a species numbering several thousand would not seem to be on the brink of extinction, but consider the following facts.

Komodo dragons are found on only three or four islands of the Lesser Sunda chain, a very limited area about one-quarter the size of Rhode Island. In addition, these particular islands are volcanic and lie within the infamous "ring of fire" around the edge of the Pacific Ocean. A nearby volcanic eruption could rain hot ash over the islands or an earthquake could cause a tidal wave, either of which could potentially wipe out a significant number of dragons almost overnight. In fact, active volcanoes are found on the islands directly to the east and to the west of Komodo.

Zoologists have found that, as a general rule, island species are especially vulnerable because of limited genetic diversity within the population and limited opportunities to migrate away from both natural and manmade problems. In addition to volcanic activity, natural disasters could include an epidemic disease that significantly reduced either the population of dragons themselves or the population of a prey species. Dragons in the wild might be very vulnerable to a drastic population drop. Population studies have found that there seems to be a natural gender imbalance of 3.5 males to every female. In other words, the population may have only a total of 450 to 1100 females distributed over the several islands.

While pressures on wild dragon populations due to human activities currently seem to be under control, where there are humans, there is always the possibility of poaching, retaliatory killings by villagers whose livestock have been attacked by dragons, overhunting of prey species, introduction of a non-native species that competes with dragons or preys upon dragon young, or ecotourism out of control. To better understand both the status and ecology of Komodo dragons in the wild, an ongoing field study undertaken jointly between NZP, the World Wildlife Fund, and the Indonesian Ministry of Forestry was begun in 1991. The information collected will be used to develop a management plan for both the species and their habitat.

Indonesian treasure International treasure

Unlike so many other endangered animals, Komodo dragons have long been acknowledged as a national treasure in Indonesia. "Discovered" in only 1910, they have been protected since 1915 under a series of native, colonial, and Republic of Indonesia laws. In more recent times (1980) Komodo National Park was established, encompassing much of their current range. Park staff have made a concerted effort to protect and manage the park and to act as guides and educators for the more than 10,000 visitors who now visit Komodo each year to see the dragons.

For those not fortunate enough to see Komodo dragons in their native homeland, dragons will, hopefully, find homes in more and more zoos as captive breeding and rearing efforts succeed. These animals will serve not only as a hedge against extinction of the species in the event of a catastrophic disaster in Indonesia, but will also serve as ambassadors for the cause of Komodo dragons in the wild and for the cause of endangered animals and conservation in general. And they will remind us that these modern dragons are just as fantastic as the fabled dragons of old.

Want to learn more?

With the hatchings of Komodo dragons at NZP, numerous articles have appeared in newspapers and magazines including Discover (December 1992) and International Wildlife (May-June 1993). Two popular books are available: for adults, Komodo: The Living Dragon by Dick and J. Marie Lutz and, for kids, Komodo Dragon by Susan Schafer. For the truly serious, the definitive work is Dr. Walter Auffenberg's The Behavioral Ecology of the Komodo Dragon, which documents his year-long study of dragons on Komodo in the early 1970's.

Editor: P. A. Jaffray