Hydrophones are specially developed microphones for listening underwater. Developed by the Navy to detect submarines, marine biologists have jumped at the opportunity to repurpose them as non-invasive recorders. The results open up the fantastic marine world in a whole new way.
Sound is an important communication tool for marine animals. Within water, sound travels better than light. This means that communication based on sound can travel further, requires less energy, and can be more complex. One of the best examples of this are whale songs.
Scientific divers Beau Masters and Esther Stuck checking out the new Hydrophone. Installation of hydrophones is done by SCUBA diving using specialised underwater gear.