What defense mechanism does the fox snake employ that mimics a venomous species?

Answer

It vibrates its tail rapidly in dry leaves to sound like a rattlesnake.

When threatened, the fox snake vibrates its tail quickly among dry leaves, mimicking the sound of a rattlesnake, which unfortunately can lead to persecution by humans.

What defense mechanism does the fox snake employ that mimics a venomous species?
rarityreptilevenomoussnakeElaphe vulpina