Asian Snakes Playing Dead

A Western Hognose Snake (Heterodon nasicus) displaying

death feigning behavior. This is a North American snake, I do

not have any photos of Asian snakes death feigning.

Death feigning behavior is known in a number of different snake lineages as well as other groups of vertebrates. It is generally believed to confuse predators so that they abandon the prey. However, another hypothesis suggests that in snakes it is a behavior triggered by the stress of the encounter with the predator. Death feigning may have many different behavioral elements, or just a few. Snake species that feed on toads often have enlarged adrenal glands, and may produce more epinephrine during an encounter with a predator - this in turn may lead to a physiological reaction that result in death feigning. Gernot Vogel and Hans Han-Yuen now report death-feigning behavior in three species of Asian colubrids: Coelognathus radiatus, Macrocalamus chanardi, and Xenochrophis piscator. The authors note that death feigning is known almost exclusively from snakes in the Nearctic, and that the behavior has been reported from only a relatively few snakes in other regions of the world. My view of this is that Nearctic snakes are better studied, there are more herpetologists active in the Nearctic and agree with the authors that many more species will be found to display this behavior.