PUFF ADDERS HAVE A LURE AT BOTH ENDS

by Whit Gibbons

April 16, 2017

I saw my first puff adder in the wild in South Africa in 2013. By the end of the week, we had found eight more. This highly venomous viper has enormous fangs, reaches lengths well over 5 feet, and the largest ones have a girth of more than 15 inches.

The head of one of the biggest ones we found was as wide as my boot. Similar to our rattlesnakes, puff adders are shy, if not provoked. Yet the species is credited with the majority of human deaths from snakes on the African continent. My assessment is that some folks excel at provoking them.

Despite the gentle nature of a puff adder, finding one was always an adrenalin-laced adventure. We were catching them as part of a research project by Xavier Glaudas and Graham Alexander of the University of the Witwatersrand in Johannesburg.

Our capture method invariably led to each snake being provoked. This is in no way an indictment of the snake. We were the ones invading their territory, grabbing them with snake tongs and eventually capturing them. All were released unharmed, nonetheless they did not take kindly to being study subjects.

Fortunately, none of us came close to being bitten. But part of the ongoing research made it clear that the same cannot be said of the prey that these impressive snakes pursue. They eat small mammals, birds, lizards and amphibians.

Puff adders are typically secretive and well camouflaged. Two of those we found were coiled only a few feet away when I heard someone say, “Stop. You’re about to step on a puff adder.” He had to point it out on the ground before I even saw it. The leaflike body pattern of puff adders renders them virtually invisible.

Glaudas and Alexander recently published a cutting-edge scientific paper on why these imposing snakes are such effective predators. Once they strike an animal and inject their highly potent venom, their meal will soon begin, because few prey survive the bite of a puff adder. But how do they get close enough to strike at wary animals that are constantly on the lookout for danger in the South African bush?

The paper, published in the prestigious professional journal Behavioral Ecology and Sociobiology, provides a partial answer. Puff adders do not approach their prey. They lure their prey to them. Using continuously recording video cameras, the researchers were able to observe how the snakes attracted other animals within striking range.

When a toad was in the vicinity of a snake, it used lingual luring, which means it flicked its long, forked tongue, mimicking a worm or insect a toad might view as prey. When the toad came closer, the snake would strike. The cameras revealed that a puff adder will also wave its tail to attract larger prey in a similar manner, a second form of luring.

The behavioral research was tedious but led to a significant biological discovery – the first documentation of two different kinds of luring being used by the same species of predator to attract prey. On an even broader scale, another conclusion by the researchers was that the study demonstrated that “these predators possess higher cognitive abilities than first expected.”

In essence, snakes have mental capabilities involving reasoning and perceptiveness that we seldom credit other animals, especially reptiles, with having. The same is probably true of many other species we consider to be “lower life forms” whose abilities we should appreciate more than we do.

Conducting field ecology experiments is a time-consuming enterprise – and with puff adders, a risky one. But uncovering details about how ecological systems work is the way we increase our understanding of the natural world.

Although I did not contribute to the research on luring behavior, I was captivated seeing these highly camouflaged, incredibly dangerous snakes up close in their native habitat. I also was glad I was not what they consider prey.

If you have an environmental question or comment, email

(Back to Ecoviews)

 

 
SREL HomeUGA Home SREL Home UGA Home