MICHEL MARTIN, HOST:
One of the casualties of the drought that may not come to mind immediately - the California soundscape. Bernie Krause is one person who appreciates these sounds. He's a soundscape ecologist.
BERNIE KRAUSE: Which means I record sounds of living organisms - nonhuman organisms, mostly - in different habitats from around the world. It's a little like...
(SOUNDBITE OF SONG, "SYMPHONY NUMBER 5 IN C MINOR, OPUS 67")
KRAUSE: ...Trying to understand the magnificence of Beethoven's "Fifth Symphony" by abstracting the sound of a single violin player out of the context of the orchestra and hearing just that one part. You can't do it.
(SOUNDBITE OF SONG, "SYMPHONY NUMBER 5 IN C MINOR, OPUS 67")
MARTIN: Over his 40-year career, Krause has recorded rainforests and deserts and mountains on seven continents. One of his favorite places on Earth to record is just 20 minutes away from his home in Northern California - Sugarloaf State Park in the Mayacamas Mountains, a place remarkably untouched by the sound of airplanes and traffic and chattering passersby.
KRAUSE: I've been recording there for almost 20 years now. The dawn, of course, is the time day when birds tend to vocalize at their highest levels, particularly in the springtime and early summer.
(SOUNDBITE OF BIRDSONG)
MARTIN: In this recording, taken in 2004, that's exactly what's going on. Ten years later, in 2014 - same spot, but there were almost no birds present in the environment, which he says is very unusual.
KRAUSE: In 77 years, this is the first time that I've heard a spring in a temperate area in United States without birdsong.
MARTIN: Krause says he'll go back this spring to record again, and with the El Nino weather pattern, he says things might perk up. Even so, Krause points to his recording as a silent alarm.
KRAUSE: It expresses to me that there is a problem, and, really, it needs to be addressed and looked at in the most profound way. Transcript provided by NPR, Copyright NPR.