Shaking Up Aquatic Substrates: Taking Lessons from Biotremology and Defining Terminology

Sound pressure and particle motion form the basis of discussions regarding potential effects of anthropogenic signals on fishes and aquatic invertebrates. However, there is a growing need to acknowledge, and understand, a third class of stimuli involving substrates. The vibrational channel is a major sensory mode in the animal kingdom. Numerous terrestrial animals, from the fruit flies to the largest of land mammals, use substrate-borne vibrations to find prey, detect predators, sense environmental change, and to communicate. Yet although many aquatic organisms reside on, in, and around substrates, how animals use vibrational information in this environment has, to date, been largely overlooked. This is all the more important given that many anthropogenic activities directly contact the seabed, eliciting significant vibrations in the substratum. To better understand the role of vibrational signals to aquatic animals, lessons can be taken from the terrestrial environment, from the discipline of biotremology. This chapter provides a refined definition of biotremology to allow inclusion of aquatic systems and discusses the alignment of terminology required to apply vibrational principles to the aquatic world. Future discussions in this area are necessary to aid the progression of both underwater noise and aquatic biotremology research.