Ask geophysicist Guust Nolet of the University of Nice in France if mermaids exist and he will tell you "Yes! And I love them!" He admits they are, of course, a rarity in the ocean. He's currently tracking two in the Mediterranean and four in the Indian Ocean. And if you want to hear them sing, you'll have to wait 10 days for them to come to the surface, unless there's been an earthquake.
Yep, these mermaids are seismically sensitive and Nolet and his team of oceanographers from the United States and France have deployed everyone of them.
For the first time oceanographers have a fleet of floating seismic detectors cruising the seas. The Mermaids (Mobile Earthquake Recording in Marine Areas by Independent Divers), provide seismic coverage of a large swath of Earth that is mostly invisible to seismologists: the oceanic crust. Unlike ocean bottom seismometers that are stuck on the seafloor for sometimes a year or more at a time, and have to be retrieved using expensive ship time expeditions to learn what data they have recorded, Mermaids will pop to the surface and transmit their data whenever they receive a signal that has a 90 percent chance of being an earthquake.