Classification and Range
Dumeril's boas occur only on the island of Madagascar, one of the world's biggest islands, located in the Indian Ocean to the east of Africa. They belong to the family of snakes Boidae, which contains the world's largest snake species, including pythons, boas and anacondas. The family Boidae is divided into several subfamilies. Dumeril's boas belong to the subfamily Boinae. The species was named after the 19th century French naturalist A. M. C. Dumeril. Dumeril's boas are closely related to the familiar boa constrictor of Latin America.
Dumeril’s boas are found in the drier parts of Madagascar: the southern and southwestern forests. Their pattern helps them hide effectively in the dry leaf litter of the forest floor.
Length and Weight
Dumeril’s boas reach an average length of 4-5 feet (1.21-1.5 m) and usually weigh less than 20 pounds (9 kg). The maximum recorded length is 7 feet (2.1 m). Females are larger than males.
20-30 years (estimate).
In the wild: Mainly small mammals At the zoo: Domestic rats
As with many other pythons and boas, a male Dumeril's boa uses his "spurs" (the vestigial pelvic remnants adjacent to his cloaca) to tickle and stimulate the female. If she is receptive, she allows him to align his body with hers, opens her cloaca, and lets him insert one of his paired copulatory organs, called hemipenes. Babies are born alive about six to eight months later. Dumeril's boas reach sexual maturity at about 3 to 5 years, males at an earlier age than females.
Probably because there are few large predators on Madagascar, Dumeril's boas have smaller litters than other boa constrictors. As a result, baby Dumeril's boas can be much larger. They are large enough to avoid being eaten by the small predator species. These snakes are independent from birth, and if they find enough food, they grow very rapidly.
Boas and Pythons
Dumeril's boas and other Madagascar boas are relatives of Latin American boas. Elsewhere in the Old World where big snakes are found, they are pythons rather than boas. How did this strange distribution of boas occur? The answer: plate tectonics. At one time, Madagascar, Africa, Australia, India, South America and Antarctica formed a single continent called Gondwana. The relatedness of the South American and Madagascar boas harks back to a time when boas were probably the dominant big snakes throughout Gondwana. As Australia and Africa approached the Eurasian land mass and were invaded by the different animals which occurred there, pythons apparently "took over" and displaced the boas. Some species of lizards found on Madagascar are in a similar situation—their closest living relatives are also in South America, almost half a world away.
Hunting From Ambush
Like other boas and pythons, Dumeril's boas can lay virtually motionless for long periods of time, waiting for an unwary prey animal to pass. When in range, the boa strikes out in a single explosive motion, using its many recurved teeth to grab hold of the prey and quickly wrap it up in the coils of the snake's stout, muscular body. Unable to breathe, the animal succumbs very quickly and is then swallowed whole by the snake.
Location at the Zoo
Currently, Woodland Park Zoo does not have a Dumeril's boa on display. The Day/Night exhibit does have many other species of snakes on display. A few examples of these would be the boa constrictor, desert rosy boa and ball python.
Dumeril's boas are listed as an endangered species. Only about 10% of Madagascar's forests remain, and they are being cut down and the wood burned or used for constructing houses. A number of conservation organizations are actively trying to preserve wildlife and nature reserves in Madagascar. By joining and/or contributing to them, you can help save Dumeril's boas and other magnificent and unusual animals of Madagascar. Dumeril's boas are kept off display.
Woodland Park Zoo participates in the Association of Zoos & Aquariums' (AZA) Species Survival Plan (SSP) for Madagascar boas. Although Dumeril's boas are not on exhibit at this time due to the lack of adequate exhibit space, we retain a number of individuals behind-the-scenes as reserve animals that are part of the cooperatively-managed, captive, self-sustaining zoo population. One day, with greater protection, these animals or their decendants may be used to restock reserves in Madagascar.
Reptiles as Pets
We do not recommend reptiles as pets for most people as they require very specialized diets and environments. We also receive hundreds of requests each year to take former pet iguanas, boas and other reptiles but we cannot accept these due to space, health and unknown backgrounds. If you need to find a reptile or amphibian a new home, we suggest you contact a local herpetological group in your area.
In the Puget Sound region, contact the Pacific Northwest Herpetological Society as a resource. If you do choose to get a reptile as a pet, please learn as much as possible about their care and the best species before making your decision and never accept wild-caught animals as pets or release non-native reptiles or amphibians into the wild.
How You Can Help!
The effort to save endangered species like the Dumeril's boa requires cooperation and support at the international, national, regional and individual levels. You can help in this cause. Join and become active in Woodland Park Zoo and other conservation organizations. Please don't buy products made from wild animal parts. Let your elected representatives know your views about protecting endangered species and wild habitats. Contact Woodland Park Zoo at firstname.lastname@example.org to find out other ways you can support conservation programs at the zoo. Discover more about snakes by contacting the Society for the Study of Amphibians and Reptiles at 303 W. 39th St., PO Box 626, Hays, KS 67601.
Sources and Suggested Reading
Glaw & Vences. 1992. A Fieldguide to the Amphibians and Reptiles of Madagscar. Published by the authors, Cologne, Germany. 331 p.
Mehrtens, John M. 1987. Living Snakes of the World. Sterling, New York, NY. 480 p.
Ross & Marzec. 1990. The Reproductive Husbandry of Pythons and Boas. Institute for Herpetological Research, Stanford, CA. 270 p.
Markle, Sandra. 1995. Outside and Inside Snakes. MacMillian Books, New York, NY. 40 p.
Resmick, Jane P. 1996. Eyes on Nature: Snakes. Kidsbooks, Inc., Chicago, IL. 29 p. Zoobooks. 1992. Snakes. Wildlife Education, Ltd., San Diego, CA. 16 p.