Interpreting the Soundscape Contributors' Notes

Tonya Wimmer: Scotian Shelf 1 and Scotian Shelf 2

Sounds of seismic survey and delphinid (dolphins or pilot whales) whistles and clicks recorded in the Atlantic Ocean off Nova Scotia, May 2001.

Contact: Tonya Wimmer, Whitehead Lab, Biology Department, Dalhousie University, Halifax, Nova Scotia, Canada B3H 4J1. E-mail: <twimmer@dal.ca>.

In January 2001, I started my master of science research with Hal Whitehead at Dalhousie University in Halifax, Nova Scotia, Canada. The focus of my research was endangered northern bottlenose whales, a beaked whale species that very few people in the world have ever seen.

Northern bottlenose whales are 30-35 ft in length and, due to the presence of a long beak, look somewhat like very large dolphins. The one place in the world where northern bottlenose whales can regularly be found is in the Sable Gully, a large underwater canyon off the coast of Nova Scotia, Canada. Previous research has shown that a large proportion of bottlenose whales are present in the canyon at any given time; however, they frequently leave the canyon and it was not known at the time where they would go. My research focused on sailing along the continental slope off Eastern North America looking and listening for bottlenose whales. While conducting these surveys off Nova Scotia, I recorded sounds made by oil and gas companies to find petroleum deposits under the sea floor. I recorded these sounds using a hydrophone towed from the 40-ft sailing vessel Balaena [1].

In order to find deposits under the sea floor, oil and gas companies project very loud sound sources from a series of hydrophones towed by a boat (this is called seismic exploration). These sounds are directed straight down from the vessel and bounce off the sea floor and the different layers of material beneath it. The properties of the returning echo tell scientists what type of material the layers are made of and where oil or gas deposits might be. The sound being emitted is very loud (typically > 200 dB) and is emitted every 12-15 seconds for several hours at a time. Seismic programs can last several weeks to months in a given area. While the majority of the sounds are directed towards the sea floor, some are carried horizontally as well and can be detected hundreds of kilometers away. The recordings presented here were made approximately 20 nautical miles away from our research location.

When listening to the second recording one can also hear whistles and the high frequency clicks of dolphins or pilot whales. Sound is the primary mode of communication for whales, dolphins and porpoises. These animals have extremely sophisticated and sensitive hearing and sound-production organs. While it is not known exactly what impact these loud human-created sound sources will have on these animals, there is evidence that they can have very serious impact on their communication abilities and have even led to the death of some animals.

Tonya Wimmer is a marine biologist who studies marine mammals in Nova Scotia, Canada. She is from Nova Scotia and believes very strongly in the protection of the marine environment, not just for sustainable human activities but, more importantly, for the many species that inhabit the ocean. She completed her master of science degree in biology at Dalhousie University in 2003 and is the president and coordinator of the Marine Animal Response Society (MARS). MARS is a charitable organization dedicated to the conservation of marine animals in Nova Scotia through rescue, education and research. She is currently working to raise funds to expand the network to the entire Maritime Provinces in Canada and develop a dedicated research survey program. She also works closely with other environmental organizations to protect the marine environment through the development of integrated management plans for human activities occurring in the waters surrounding the Maritime Provinces.

Andrea Polli and Joe Gilmore: N. April 16, 2006

Sonification of measured (National Oceanic and Atmospheric Administration's Arctic program) and model weather data, April 2006. Data modeling by Patrick Market, University of Missouri.

Contact: Andrea Polli, Department of Film and Media Studies, Hunter College, 695 Park Avenue, New York, NY 10021, U...