The Earth is mostly ocean, yet the surface of the moon is better understood than the seafloor. In order to gain just a little bit more knowledge, scientists are now turning to sound, rather than light, to map our watery realm. Remote submersibles and new sonar have revealed glimpses into the ocean: fish shoals stretching 25 miles long, invisible whale migrations, and entire ecosystems revealed in the echoes of the bodies of squid, herring, and billions of other organisms.
But it's the sound recordings--notes of wildlife going about their business--that are most captivating. Now, you can eavesdrop on their world. Using a similar technology to Skype, an growing array of underwater microphones called hydrophones are broadcasting around the clock audio to the world.
Off the coast of British Columbia, a permanent set of listening stations has been installed by the Heiltsuk Integrated Resource Management Department. The broadcasts, often a steady swoosh of water punctuated by the chirps and whistles of whales, play on the local FM station in Bella Bella, British Columbia, as well as across the Internet. On a recent recording, the five hydrophones picked up everything from thrumming boat motors to the wild sounds of transient killer whales. You can even hear the clatter of earthquakes at times. You can listen to them all live and replay highlights at PacificWild.org.
For a truly spectacular audio experience, head north to the poles to hear "life under the Antarctic ice." Transmitted by two hydrophones that are operated by PALAOA, a wind and solar powered autonomous observatory located on the Ekström ice shelf, the hydrophones resemble sounds from another world.
The broadcasts are ethereal--whistling cetaceans vie with calving icebergs in a mysterious rush. The technological feats required for broadcasting are also impressive. Data is transmitted via wireless LAN from PALAOA to the German Neumayer Base and then through a permanent satellite link to an institute in Germany. The result is another worldly, and unexpected, auditory journey. "You might need to pump up the volume," writes PALAOA, "but beware of sudden extremely loud events."
If that's not enough, here is a directory of more marine stations courtesy of Pacific Wild:
Orca-Live.net: Live orcas from Hanson Island near Vancouver Island, Canada
VENUS Canada: Real-time hydrophones off Fraser River mouth
NEPTUNE Canada: Real-time hydrophones at the entrance to the Strait of Juan de Fuca
Jupiterfoundation.org: Humpacks live from Angoon, Alaska, and Kamuela, Hawaii)
Alfred Wegner Institut: Live hydrophone from Antarctica!
[Image: Whale via Shutterstock]