Common throughout most of South Africa (excluding mountain-tops, true desert, and dense forests), Puff Adders are slow-moving and excitable snakes with potently cytotoxic (tissue destroying) venom.
Puff Adders rely on their camouflage to remain unseen, and when disturbed they coil into a defensive "S"-shape and hiss loudly (hence their name). They usually move in a straight caterpillar-like motion but may move in a more rapid serpentine motion when trying to get away.
They are responsible for a large number of bites because unlike most other snakes they won't move off when approached, and their exceptionally fast striking ability. Their fangs fold back against the roof of their mouths when not in use, and can be up to 18mm in length - this video provides an example of how Puff Adder fangs work.
As ambush hunters, Puff Adders sometimes wait motionless in one spot for hours at a time. They feed on rats, mice, birds, lizards, and occasionally other snakes.
Viviparous, they give birth to 20-40 young in the late summer months.