Sound Inventions
 Chris Clark listens to sounds of fin whales from a microphone array towed by a boat in Baja California. Photo by Jane Moon Clark |
By using technology to go beyond the barriers of human limitations,
the
Lab's Bioacoustics Research Program (BRP) is opening up vast new
possibilities for the study and monitoring of wildilfe. BRP engineers
have developed autonomous recording units (ARUs) that they loft into
the air with balloons, strap to trees, or send to the bottom of the
ocean to record the sounds of animals for months at at time.
For example, BRP researchers are flying recording units over
military bases to detect the sounds of endangered Golden-cheeked
Warblers and Black-capped Vireos. They are documenting the population
numbers and movements of endangered northern right whales using
underwater microphone arrays, and mounting recorders on trees to
monitor forest elephants that are rarely seen in the dense African
rainforest.
Now that it's possible to collect massive amounts of acoustic data
with ARUs, the Lab is developing software that screens out unwanted
sounds and produces spectrograms for identification, eliminating years
of tedious analysis.
Says Russ Charif, a research support specialist, "These technologies
enable us to extend our senses into environments where we cannot go or
where our senses are too limited, and to detect and track animals on a
geographic scope otherwise unattainable."
Related articles:
Breaking the Sound Barrier: Seventy-five years of innovation bring the sights and sounds of animals to life. BirdScope, Winter 2006.
Deep Listening: New tools open up the world of animal sounds. BirdScope, Winter 2006.
Raven's New Frontier. BirdScope, Summer 2003.
Up, Up, and Underway. BirdScope, Summer 2002.