Gopher Snake - Master Impersonator!

Pacific Gopher Snake blending with the leaves on the trail

This is the rare case when I saw the snake before it saw me. This Pacific Gopher Snake (Pituophis catenifer) is five feet long.

The coloration of this one is unusual to my eye. I’m 200 miles south of my home territory and the snake looks a bit darker than the ones near me.

Pacific Gopher Snake. Pay attention to the pupil and the “mask” across its forehead.

Gopher snakes are constrictors that eat rodents, birds, eggs, insects and smaller reptiles. They are diurnal, so it is not uncommon to see them. I routinely notice them in grassland, mixed forest, and chaparral.

Do you do Impressions?

One of the most fascinating things about this snake is its defensive behavior. It looks very much like the venomous rattlesnake. When it feels threatened, it becomes the master of impersonation. It coils like a rattlesnake and flattens its head to look like the pit viper. But that is not all! It shakes its tail back and forth to mimic the rattlesnake. The tail may rub on leaves to create a buzzing sound. The snake also hisses at an unusually loud volume. This hiss sounds much like the buzz of a rattlesnake. This snake would make a terrific poker player!

How can I tell that it is a gopher snake and not a venomous rattlesnake? The pupil in the eye is round and a “mask” runs across its forehead between its eyes, like a raccoon’s. It is just barely visible in the close-up picture above. When not aroused, the head is the same width as its body. It also just “looks different” (I know that doesn’t help).

Another Gopher Snake. The arrow indicates the mask.

What I find intriguing about this snake is its behavior. I can picture how the color adaptation would evolve over time. Snakes looking like rattlers would not be predated as often. But I can’t fathom how the behavioral mimicry evolved. What mechanism produces a snake that can mimic another so perfectly? It’s not like this snake graduated college. I find it simply amazing.

Are there snakes like this near you? Have you seen other examples of behavioral mimicry?