Puff Adder

## About

A puff adder.

The puff adder ***(Bitis arietans)*** is a highly venomous viper species which is widespread throughout the African continent and southwest Asia. Puff adders are mostly brown in colour but additionally possess triangular markings of tan and black colouration which run down the dorsum. They have keeled scales and a triangular head, common amongst viper/adder species. This more monochromatic pattern helps camouflage the adder in similarly coloured surroundings. They have solenoglyphous fangs which harbour a damaging hemotoxin (the effects of which are discussed in Relationship with Humans). Like most adder species, the puff adder has a relatively thick and stout body and rarely measure over 1m (3.2ft) though some individuals have reached a recorded 1.5m (4.6ft) in length. Despite their small length they are relatively heavy-bodied, weighing 4.5-6.8kg (9.9-14.9lbs). The sexes are identical with the exception of the female's slightly shorter tail.

## Diet

Puff adders hunt and eat a vast array of terrestrial vertebrates, including lizards, smaller snakes, small tortoises, birds and frogs but most commonly eat rodents. They have also been known to occasionally prey upon small deer species. Juvenile adders are inclined to eating mostly small species, such as rodents, frogs, toads and insects. It is an ambush predator and hunts using lingual or caudal luring, before striking and using its hemotoxic venom to subdue prey. When striking, a puff adder will not hold on its prey in order to avoid injury, especially when hunting large species.

## Conservation Status

Puff adders are classed as least concern by the IUCN due to their widespread range and minimal threats.

## Range and Population

The puff adder occurs throughout sub-Sharan Africa and the Arabian peninsula, with one isolated relictual subpopulation occurring in Morocco. They avoid densely forested regions such as central Africa and the Congo as well as the Sahara, due to the species requiring a permanent water body nearby in order to survive. Puff adders are most frequently found inhabiting semi-arid grasslands, savannas, open woodlands/forests and deserts and are less commonly found in rainforest environments. Puff adders can be found at elevations of up to 3,500m (11,482ft). The population is unquantified as of yet but is known to be widespread and stable. The species is however, incredibly uncommon in Morocco and may have gone extinct in the Moroccan town of Essaouira.

## Behaviour

The puff adder is a solitary and aggressive species which has been known to puff up to a larger size (via filling its throat with air) and hissing to appear more threatening to potential threats, giving the species its name. They will also position themselves in an "S-posture' as a final warning to threats before striking. Breeding season occurs from October-December, where a male will court a female by flicking his tongue at her, before climbing onto her back and beginning to writhe. He will continue squirming and twisting until the female either opens her cloaca or she rejects him. If successful, the male will use one of two hemipenes to begin intercourse, lasting up to a few hours. The female will lay a clutch of 20-40 eggs during April, though clutches of up to 80 eggs have been reported. Both males and females are promiscuous and can have multiple mates each. Unfertilised eggs are known to be dismissed and discarded by the female. A juvenile adder will reach sexual maturity at four years.

### Relationship with Humans

Puff adders are incredibly dangerous to humans and their hemotoxic bite has been known to cause extreme pain, swelling, tissue necrosis and the disabling of the blood's ability to form platelets in victims, which typically form clots and help with limiting blood-loss. It is advised medical care is sought out immediately. An estimated 32,000 people die from puff adder bites in Africa annually and so, the species' venom is incredibly valued for its use in antivenin products. It is however, said that death from the bite itself is rare and fatalities typically occur due to secondary infections or poor/no medical care.

## In Captivity

Puff adders can be found in zoos worldwide, notably in Europe where they have become popular. Puff adders are naturally bad-tempered animals and in captivity many never calm to the presence of humans, continuing to bite and hiss even when used to a captive environment. It can also be noted that puff adders should not be overfed in captivity, as they have a naturally slow metabolism and this can result in regurgitation or death.

## Sources

* IUCN Red List of Threatened Species - https://www.iucnredlist.org/species/197461/2485974
* Puff Adder | Wikipedia - https://en.wikipedia.org/wiki/Puff\_adder
* Puff Adder | Animal Diversity Web, University of Michigan Museum of Zoology - https://animaldiversity.org/accounts/Bitis\_arietans/
* Puff Adder | ZOOINSTTUTES - https://zooinstitutes.com/animals/puff-adder-201/
* Puff Adder | Kruger National Park - https://www.krugerpark.co.za/africa\_puff-adder.html