Posts Tagged ‘spreading adder’

“Spreading Adders”

Thursday, April 29th, 2010

The hiss of an Eastern hog-nosed snake as it spreads its neck and acts like a cobra can be quite startling, but it is all bluff. Eastern hog -nosed snakes are completely harmless, and it is nearly impossible to get one to bite. It is no accident that they seem to show up when toads are active. Hog-nosed snakes specialize on toads, eating almost nothing else. Colors and patterns of hog-nosed snakes vary from nearly all black to reddish with various shaped markings, and younger hog-nosed snakes seem to be brighter in color than older and larger ones.

An adul;t (top) and juvenile (bottom) Eastern hog-nosed snake

An adult (top) and juvenile (bottom) Eastern hog-nosed snake

When first disturbed, hog-nosed snakes go through their hissing and spreading display, hence the nickname “spreading adder.” However, if they are bothered a bit more, they switch their behavior to a ridiculous series of movements in which they appear to act as though they have died, going so far as to roll over on their back, open their mouth, drag their tongue in the dirt and lay there motionless. If you wait a few minutes, they will roll their head over and look at you. If you roll them over so that they are upright, they quickly roll back over upside down. And, if you wait long enough, they roll over and crawl away. What could possibly be the advantage of doing this? One would think that simply lying there would make it easier for a predator to eat them.

Starting in the bottom left, follow clockwise, the deith-feigning sequence of a hog-nosed snake

Starting at the bottom left, follow clockwise, the death-feigning sequence of an Eastern hog-nosed snake

If you watch carefully when hog-nosed snakes first start rolling over, you will notice that they cover themselves with bodily wastes released from their cloaca as they twist and coil during their death feigning act. Recall that they eat toads, almost exclusively. Toads eat ants and beetles that produce chemicals (alkaloids) for defense, and toads in turn produce strong chemicals that are released from the large glands (paratoids) just in back of their head that make them very bad tasting and sometimes toxic (don’t lick a toad!). So, when Hog-nosed snakes eat toads, they are also eating a bunch of very bad-tasting chemicals. By covering themselves with excrement, Hog-nosed snakes make themselves very bad to eat. The “playing dead” likely keeps them from being injured while a predator determines that they are not as tasty as they first appeared to be when they were crawling along.

Threat display of an adult Eastern hog-nosed snake. Note the raised tail and the flattened neck, hence, "spreading adder."

Threat display of an adult Eastern hog-nosed snake. Note the raised tail and the flattened neck, hence, "spreading adder."