Salish Sea Hydrophone Network
Goals: The goals of this project are to monitor underwater noise pollution levels, detect: the sounds of endangered southern resident killer whales, and raise awareness about underwater sound.
How it works: In October 2006, two hydrophones (underwater microphones) were installed beneath the Port Townsend Marine Science Center pier. These hydrophones make up one of five nodes of the Salish Sea hydrophone network, a project sponsored by NOAA and The Whale Museum. This network allows scientists and the public to listen to orcas, or killer whales, and other marine animals in Puget Sound waters.
Each node of the network consists of at least one hydrophone, a cable to bring the sound signal onto land, a “sound board” to digitize the signal, and a computer to analyze the signal and stream it via the Internet. The PTMSC node consists of two hydrophones located 10 meters under water. Having two hydrophones allows listeners to determine where the sounds originate.
Even though software is used to distinguish animal from other underwater sound, human ears do a better job. So, volunteers monitor the network from their home computers anywhere in the world, and alert the rest of the network when they hear whale sounds. Sometimes boats or onshore monitors are deployed to observe the whales while they are making sounds. Researchers hope to learn more about the uses of orca communications and whale migration patterns.
Even when the Marine Exhibit is closed, you can listen to the sounds of Puget Sound on your computer; at the dock, you can turn a knob on the back of the exhibit building to activate the exterior hydrophone speakers.
Number of PTMSC volunteers: Hard to say; anyone can listen to the network on their home computer to monitor underwater sounds.
Is this project open to new volunteers? Definitely. Go to www.orcasounds.net to sign up. You can listen to any of the nodes live at http://orcasound.net. The more you listen, the more valuable your observations as you learn to differentiate between human and animal-made sounds.
Hear our hydrophone now
Tap into the larger Salish Sea hydrophone network
Hear recorded orca sounds
See orca video
Connect to the whale museum website