This brightly coloured puff adder was seen crossing the road during a field trip earlier this year to the Baviaanskloof (a UNESCO World Heritage Site). It is one of the larger of the species noted on many field trips in South Africa. Measuring at least 1 m (perhaps slighty more), the snake typically moved in a caterpillar like fashion, leaving a straight track across the road.
This snake ambushes prey which includes mainly mice and sometimes birds. Other snakes have also been recorded in the diet (including a single record of a tortoise). The venom is cytotoxic and a bite yielding more than 100 mg is fatal to humans. Yields are large (100-350 mg) and the long fangs inject the venom deeply.
Disturbed puff adders strike easily but adopt a strike pose before doing so. Usually a deep hollow hiss is given as a warning. 60% of serious snake bites are caused by this species and it is responsible for most of the fatalities in southern Africa.
Reference: Field guide to snakes and other reptiles of southern Africa by Bill Branch (Struik, 1998).