Puff Adder (Bitis arietans)
Species: Puff Adder (Bitis arietans)
What does the name mean? I have been unable to find the origin, or meaning, of the term “Bitis” except that it used to describe the African vipers that have a common threat display that involves hissing loudly whilst inflating and deflating their bodies, keeled scales, and a distinctive triangular head. The Puff adder (Bitis arietans) was the first to be described (type species) by German naturalist Blasius Merrem in 1820. All subsequent adders found in Africa with similar characteristics have been placed in this genus.
The first description the species was Clotho arietans. “Clotho” was the Greek Goddess of fate, the spinner of the thread of destiny.
The word “arietans” is also quite vague in its origin but more than likely is derived from the Latin words “arieto”,”arietare”, and “arietatus” which when translated means “to strike violently”
Description: This is a thick robust heavily built snake. It has the distinctive triangular head normally associated with the genus.
The average length for these snakes is 90cm-1.1m (2.95ft-3.28ft). There are however records of specimens exceeding 1.9m (6.23ft) although this is rare. What these snakes lack in length, they make up in bulk. Specimens exceeding 4kg (8.8 lbs) are not uncommon.
The puff adder (like most members of the Viperidae family), is an ambush predator and thus colours vary greatly depending on the geographic location. It is also not uncommon to find a variation in colour within a relatively small area.
Dorsally, colours range from yellow,light brown, dark brown, orange, ochre, tan, beige overlaid with black lighter edged chevron shaped bands on the body and black cross-bands on the tail. Typically there are between 16-23 chevron shaped markings. The belly is white or yellow with several dark blotches randomly scattered along the length of the body.
The markings on the head consist of two oblique dark bands that extend from the eye to the supralabials, and dark blotches on the crown and between the eyes.
The term “cryptic colouration” is often used to describe the appearance of puff adders.
The colouration and heavily keeled scales give this species a generally dull appearance, although there have been some particularly bright specimens recorded from some regions (Eastern Cape). A striped phase of the species has also been recorded.
These snakes have “front-hinged” fangs situated at the front of the mouth which fold into the roof of the mouth within a protective sheath when the mouth is closed. When the mouth opens the fangs unfold outwards, similar to the action of a “switch-blade”.
Venom: The venom is cytotoxic (tissue destroying). This species is responsible for more fatalaties than any other African snake, including the Black Mamba . This statistic is slightly misleading and bears no relevance to the potency of the venom itself. Although the puff adder is classified as the most dangerous snake in Africa, it is neither the deadliest, nor the most venomous snake in Africa.
Although bites are common, only a small proportion results in human fatality.
This may seem confusing at first, but the answer lies in the statistics. In South Africa alone the puff adder is responsible for 60% of all recorded snakebites, the remaining 40% can be divided between the other venomous snakes found in the region which includes the cobras, mambas and other members of the genusBitis.
The average venom yield per bite is between 100-300mg with the maximum yield of around 700mg.100mg is fatal in humans. A bite from this snake may result in death after 26 hours if treatment is not received.
Deep necrosis may result in severe cases which may lead to the amputation of the affected limb, and extensive reconstructive surgery is often needed.
Death usually results from kidney failure and other complications as a result of extensive swelling.
Distribution: This species is the most common and widespread venomous snake in Africa. It’s geographic range includes: South Africa, Namibia, Swaziland, Lesotho, Botswana, Zimbabwe, Mozambique, Malawi, Angola, Zambia, Tanzania, Kenya, Uganda, Burundi, Rwanda, Congo, Democratic republic of Congo (Zaire), Gabon, Equatorial Guinea, Burkina Faso, Cameroon, Nigeria, Niger, Central African Republic, Benin, Togo, Ghana, Ivory Coast, Liberia, Sierra Leone, Ethiopia, Eritrea, Guinea, Guinea Bissau, Gambia, Senegal, Mauritania, Mali, Chad, Algeria, Morocco, Saudi Arabia, Oman, and Yemen.
Habitat: The Puff adder is found in all habitats except for true deserts and rain forests and mountain tops. The preferred habitat for the species includes open grassland, savanna, open woodlands and rocky outcrops.
Habits: Puff adders are described as being both diurnal and nocturnal although they are mostly active at night.
This species “willingness to bite” is greatly exaggerated. As with all snakes, it is reluctant to bite unless provoked. Although I do not reccomend this, it is quite possible to stand next to a puff adder without enticing a bite.
The species is quite sluggish preferring to rely on its cryptic colouration and patterns for camouflage, and will only bite if trodden on, or surprised.
Despite its “sluggish” behaviour, this is arguably the fastest striking snake in the world. It can strike within.25 of a second both forward and to the side. Stories of them being able to strike backwards are unfounded and untrue.
These snakes are predominantly terrestrial although they have been observed climbing shrubs and small bushes.
As a result of this most bites from this species occur below the knee.
This snake is fond of swimming, and can often be found on roads at night.
When disturbed these snakes will coil themselves into a defensive posture and hiss loudly, hence its common name “Puff adder”. It is a warning best heeded!
Reproduction: Puff adders are ovoviviparous. Ovoviviparity means that the young develop within an egg, and are nourished by the egg yolk, but instead of being incubated externally, the eggs are retained within the organisms body until they are ready to hatch. The average litter size is between 20-50 young. Litters of80 young have been recorded on several occasions. The record size of a litter was recorded by a large female which had a litter of 156 young.
The young measure between 13-20cm (5.1-7.87in).
The gestation period in this species is between 7-9 months although some records show a gestation period over 12 months.
Mating usually occurs in spring.
Diet: Prey items usually consist of rodents and sometimes birds.
This species does not actively hunt, but rather lies in ambush and waits for prey to come within striking distance. Prey items are seldom gripped, instead, once envenomated, the prey is released and later”tracked” by smell.
Subspecies: Two races are recognised:
Bitis arietans arietans, the common widespread puff adder.
Bitis arietans somalica found in Somalia and northern Kenya.
A third subspecies was proposed, namely Bitis arietans peghullae, but has been rejected.
Conservation StatusICUN Red List: Not evaluated
CITES: Not Listed