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From KQED.

If you grew up here in the Bay Area or if you've lived here a long time,

I bet this sound is familiar to you.

Tree frogs, a quintessential soundtrack to the Bay Area.

These aren't your stereotypical big, bloated bullfrogs.

They're little green frogs, just a couple

inches long, with bulging eyes and giant toe pads that allow them to climb trees. They're

especially noisy during the springtime, which is their mating season. I used to wonder how people

that live next to them could sleep in the springtime because the frogs were so loud. It was really cool. Dave Ellis grew up in the South Bay City of Saratoga.

We live about a quarter mile from the creek, and you could hear the tree frogs that far away.

When he was a kid, he used to go to the creek, which ran through a community college campus, to try to see the frogs for himself. We used to go to West Valley College, and we used to catch him in the creek there, because they had like a little bridge. You could climb down. It was really easy to get into the creek, and you could hear lots of them there, too. Dave still lives in Saratoga, not too far from that creek, but now, come springtime, it's silent.

That's so weird.

It used to be so loud this time of year, and it's just dead silent.

All of a sudden the silence was just deafening.

He says he's hardly heard a single frog sound for years.

So I was wondering what happened.

...