Photo Courtesy: [William Warby/Flickr] / CC BY 2.0
The boomslang tree snake is fatally poisonous and a bit of a pop culture phenomenon
The boomslang snake is a member of the Colubridae family of snakes. This snake family is the largest in the world and you can find them everywhere on the planet except in Antarctica. If you’re being formal, you would call a boomslang by the name Dispholidus typus, but Its more common name is a combination of the Afrikaans and Dutch words for tree (boom) and snake (slang).
Boomslang snake physical characteristics
Boomslangs are sexually dimorphic, which means that the male and female of the species look very different from each other. A female boomslang is usually olive-brown; males are much brighter creatures. You’ll find male boomslangs that have green, yellow and pinkish bodies with black or blue-edged scales. Hatchlings and young boomslangs are grey, with massive green eyes. Their coloring begins to change after about one month.
A typical adult boomslang may be between three and five feet long, though they can be longer than six feet. They’re lightweights but can still pack a punch. On average, a boomslang weighs two-thirds of a pound.
Boomslangs have their largest teeth at the back of their mouths — they’re “rear-toothed” snakes (opisthoglyphous). The seven or eight teeth in the front part of the mouth are followed by three large, grooved fangs placed under each eye. Those fangs are three to five millimeters high. They aren’t always three to five millimeters high, though, since a boomslang can lay those fangs down when they aren’t in use. Boomslang can — and must — open their mouth wide (as much as 170 degrees) in order to grab hold of prey with those teeth and to inject venom into them. (More about that venom later!)
An average boomslang’s life lasts for eight years. Those lives sometimes end when the boomslang are eaten by large carnivorous birds, like secretary birds, falcons, kestrels, ospreys and raptors.
Natural habitat
Boomslangs are found in sub-Saharan African, meaning the countries in Africa that lay south of the Sahara Desert. The snake is most commonly found in the central and southern portions of sub-Saharan Africa, particularly in Botswana, Swaziland, Namibia, Mozambique, and Zimbabwe, but specimens have also. been encountered as far north as Chad and Nigeria, and as far east as Guinea.
A typical adult boomslang may be between three and five feet long, though they can be longer than six feet. They’re lightweights but can still pack a punch. On average, a boomslang weighs two-thirds of a pound.
If you’re looking for a boomslang in sub-Saharan Africa, you’re most likely to find them in wood grasslands, arid savannas, karoo scrubs, and lowland forests. As their name suggests, they’re almost entirely arboreal, meaning they live almost entirely in the trees. They can climb and glide through trees to hunt.
Boomslang snake’s diet
Boomslangs primarily eat birds (including eggs and nestlings), lizards, frogs, chameleons, insects and other prey small enough to swallow. Whatever they eat, they swallow whole. They’ll even eat snakes, including other boomslangs.
This species of snake is diurnal, meaning they’re active during the day and asleep — or at least quiet — during the night. When it’s cooler, a boomslang will brumate or lay dormant for a time, often inside weaverbirds’ nests that are woven out of vegetation.
As a general rule, boomslangs are timid creatures that avoid anything that’s too large to kill and swallow.
Reproductive behavior
Boomslang breeding season lasts approximately from July to October. Male boomslangs will sometimes engage in ritualistic combat over the right to mate. In addition, like most fish, amphibians, reptiles, and all birds, boomslangs are oviparous. This means that they lay eggs — as many as 30 at a time (or “per clutch”).
A female boomslang often lays her eggs in a hollow tree trunk or log. The eggs incubate there for roughly three months before being hatched. When hatched, a baby boomslang is about eight inches long and harmless. They don’t develop poison until they’re about a foot-and-a-half long and as thick as an adult’s little finger.
More than a pretty face — beware of the poison
A human being bitten by a boomslang will experience headaches, nausea, mental disorders, and sleepiness on the way to potentially more serious side effects. Eventually, victims will bleed from their gums, nose, and even eyes before dying of hemorrhage or respiratory arrest.
The boomslang is among the minority in the common Colubridae snake family. Most colubrid snakes are not poisonous but the boomslang is different. It has a haemotoxic venom that compromises the blood clotting system. That venom destroys red blood cells, causing hemolysis, disrupting blood clotting, and producing tissue damage and organ failure.
Just 0.0006 milligrams of venom is enough to kill a bird within minutes. A human being bitten by a boomslang will experience headaches, nausea, mental disorders, and sleepiness on the way to potentially more serious side effects. Eventually, victims will bleed from their gums, nose, and even eyes before dying of hemorrhage or respiratory arrest.
A victim’s body might seem to turn blue because of all the internal bleeding. Boomslang venom is slow-acting, though, so the symptoms emerge slowly over many hours or even days. This will become all the more real when you meet Karl P. Schmidt shortly.
What kinds of treatment are available? A monovalent anti-venom is produced by South African Vaccine Producers located in Sandringham, Johannesburg, South Africa. (Monovalent means that antivenom for boomslangs is effective only against the single species. Polyvalent antivenoms can respond to venoms from more than one species.) The use of this anti-venom can make the difference between surviving and succumbing to the snake’s poison.
The story of the boomslang’s first known victim
Everyone thought boomslangs were harmless and beautiful until September 26, 1957. How can we be sure of that date?
Karl P. Schmidt knew a lot about snakes. He had worked for New York’s American Museum of Natural History and for Chicago’s Field Museum and also had been president of the American Society of Ichthyologists and Herpetologists from 1942 to 1946. With this background, he had lots of experience handling deadly snakes.
In September 1957, he was sent a young boomslang snake by Marlin Jenkins, director of the Lincoln Park Zoo to be identified. While handling and underestimating the power of the snake, he was bitten on his thumb.
At that time, rear-toothed snakes like boomslangs were not thought to be poisonous. So Schmidt was not alarmed. Rather than seek medical attention, he took occasional notes of the effects of the snakebite from 4:30 in the afternoon until 6:30 the next morning. His notes of 6:30 the morning after the bite said his mouth and nose were bleeding, but not excessively. At 1:30 that afternoon, he vomited. When help reached him, he was unresponsive and sweat-covered. By 3:00 p.m. he was dead as the result of respiratory arrest and cerebral hemorrhage.
Since Schmidt’s death in 1957, seven other people have reportedly been killed by boomslang venom.
Pop-culture phenomenon
If the name boomslang sounds familiar and you’re not a snake fan, there are a few possible reasons for that. In Harry Potter and the Chamber of Secrets, the shredded skin of a boomslang snake is a required ingredient for making Polyjuice Potion. Other ingredients include lacewing flies, leeches, fluxweed, knotgrass, and powdered horn of a Bicorn.
There are other literary references to this snake. Long before Harry Potter came Agatha Christie. In her novel Death in the Clouds, the venom of a boomslang snake was used as a murder weapon. Moving from movies and books to the small screen, an episode of Quincy, M.E. featured boomslang venom as a murder weapon too.
Comic books more your style? You’ll recognize Boomslang as the name of a Marvel Comics supervillain – part of the Serpent Society that first appeared in Captain America #310 in October 1985.
If you’re going to encounter a boomslang anywhere, it seems safest to do so in the pages of a novel, on the screen of a movie theatre or television set, or in the pages of a comic book.
A deeper dive – Related reading from the 101:
- 40 Deadly Animals In The United States, Ranked | Science101
There are plenty of dangerous animals much closer to home… and some that may surprise you. - Learn all about the green anaconda | Science101
“Anaconda” is a word that pops up all over popular culture. What do you know about the anaconda?