History of underwater sound

Fishermen have used sounds to attract fish for thousands of years.  Aristotle first described fish sounds 2000 years ago and Homer also discussed sound attraction for catfish. (Janko 1900)  Maori��Indians of New Zealand used flax sacks with rocks in them to jerk in the sea to bring fish in with sound.  (Doogue, 1974)  Spearfish divers twang their rubber on the spears or use voice grunts to attract fish.  Fishermen throughout the world have used beating sticks on the water to attract fish. (Steinberg 1957)  The technical term is positive phonotaxis.  Salmon fishermen “stone the hole” by throwing in stones to excite the fish with sound.  The Japanese have their “Fish Inviter”, for attracting fish by noises simulating the splashes of birds attacking bait fish at the surface.  Those seeking catfish in Europe use the “clonk” stick to bring in the fish by clonking the water with serious sound. (Solymos 1965)  It is so effective, it is outlawed in certain areas.  Fish produce sounds through “stridulation”, the grinding of teeth or spines, amplified by the swim bladder.  They also produce sounds with “sonic muscles”, that vibrate the air bladder as an amplifier.  Many other sounds occur when fish are feeding or spawning, attracting other fish.  Herring have even been found to communicate with “farts”, alerting predator fish to their location.  They produce swim bladder gases for this purpose. There is an interesting story of the prime minister of Sweden getting his Navy to explore the sounds of Soviet Spy Submarines in Stockholm harbor with hydrophones. He was sure they were spying on Stockholm until aquatic acoustic researchers told him the sounds were “Herring Farts”.

Some fish are named for the sounds they make, such as the croakers, drums and grunts.  Many of these sounds are found in this app to improve your fishing success.  Most of these sounds I have recorded underwater with a hydrophone.  Some are produced musically and analyzed with Fast Fourier Transform to render them precise.  The first three sounds are “herring farts”, “Crawfish eaten by Predator Fish” and “Panfish eating beetles”.  These  come with the $0.99  app as well as all the saltwater and dolphin calls. Over 70 other calls are available.
The science of underwater acoustics began in 1490, when Leonardo da Vinci wrote, (1)  ” If you cause a ship to stop and place the head of a long tube in the water and place the outer extremity to your ear, you will hear ships at a great distance from you ”

Isaac Newton also wrote his, Mathematical Principles of Natural Philosophy, which included the first mathematical treatment of sound.

Daniel Colladon and Charles Sturm , in 1826 measured the speed of sound underwater in Lake Geneva.  They were within 2% of current measured��speeds underwater.  The speed of sound under water travels 4.4 times faster than in air. This is a benefit to fish.  Whales communicate with sound,  hundreds of miles away.