How do animals detect seismic activity?
siesmoreceptors can detect vibrational activity
Many animals communicate by producing Rayleigh waves (type of siesmic waves) on the substrate. This substrate can be anything including earth, spiders web, water surface, etc. Also it can be a mechanism of food detection as in spiders. They detect prey with the help of vibrations in the web created when an insect gets caught.
Elephants can detect seismic signals very well. They produce sounds with such high amplitudes that these can travel through the earth. These can be received by other elephants and as elephants have the largest cerebral cortex among all mammals, they can interpret these signals.
Many other animals also use seismic cues for different purposes. For more information, refer to this link.