The puff adder snake can weigh up to 13 lbs and grow to 6 ft. long. Hunting by ambushing small rodent and amphibians, puff adder venom, one of the most toxic of any viper, immobilizes its prey though the adder’s long teeth and forceful bite sometimes kill it without any help from the venom.
Unlike many snakes, the puff adder doesn’t slither away from approaching footsteps. Instead this thick-bodied poisonous viper makes a soft hiss or sigh and then strikes. The warning can be difficult to hear, and often the snake strikes before a human can get away. Thousands of people in Africa used to die each year from puff adder bites. Now, antivenom saves up to 95 percent of the human victims.
These snakes are accomplished swimmers and climbers. Active mainly at night, puff adders spend their days either warming themselves on rocks or hiding in leaf litter or shrubs. They hibernate through the winter months, waking with the warm weather in spring.