Last night my friend Nancy and I went to a local frog pond to spend some time sitting with the singing Pacific tree frog males. With the onset of warmer weather in February, male frogs head to the ponds and start to sing, calling in females to mate and start the next generation. As the days have lengthened into April, the singing has gotten more intense. Last night we decided to pay an after-dark visit, to experience the chorus, to look for frogs and hopefully, to find some egg masses. We were not disappointed.
My friend Barbara lives on the edge of a wetland, which also next door to a place where wetland plants are commercially grown in "wet beds". These wet beds are shallow temporary freshwater ponds, which for the tree frogs are ideal for raising tadpoles. Barbara has been hearing frogs singing from the wet beds for several weeks now. This was our destination.
So last night we left the house at 8:45 pm in the near-dark. It had reached 60 that sunny spring day and was still fairly warm. As we drove through the quiet night, the skies were dark and clear with a gibbous moon; the stars showed a frosty light, and Orion stalked the Lepus the Hare in the western sky.
We arrived at the wetland and parked, getting quietly out of the car, hoping we would not alert the frogs. Not a chance. As we sneaked up on the wet bed, it was silent as the tomb and we thought we'd blown it. We tiptoed around, setting up our chairs, fumbling with our flashlights, cameras, hats and trying hard not to giggle in the enforced silence. We didn't succeed at that, either.
We used our flashlights to scan the surface of the water and found a couple of frogs, looking very dead, but just playing possum. As soon as the light moved away, they hid themselves away.
We also searched for egg masses: I'd been checking the wet bed several times over the last 3 weeks and had not yet seen any. But viola! we were rewarded: several small clusters of greenish gel, containing fat round white eggs showed up, attached to the hardware cloth lining the bottom of the wet bed. These looked very new, very freshly laid.
Finally we settled down, turned off the lights and prepared to wait. I was not hopeful, thinking it might take 20 minutes or more. But I underestimated the hormonally driven males: within 2 minutes the chorus began again. There was one frog about 2 feet away from us who started things off. This was likely what they call the choirmaster: the leader of the band who gets things going. Several times over the 45 minutes we were there, the frogs quieted briefly and always, when they started up, his was the first voice to start up the songs.
We turned our flashlights on occasionally, trying to find all these calling frogs. We could only find two: one we believe was the choirmaster, sitting just half-submerged about 2 feet away from us, at the far corner of the wet bed, facing in. He kept his throat pouch inflated throughout; even when not singing, it was inflated. Unlike the other frogs, he did not move when we had the light on him. We speculated that these males might actually divide the wet bed into good calling territories; perhaps he had a primo one, and was unwilling to abandon it.
Other frogs were hiding under the plastic containers that held the plants. That seemed like a good choice for a couple of reasons: they were protected from predators, and the thin plastic might act as a resonating chamber, allowing their calls to be even more alluring to females ready to mate.
So we sat, in the dark, the frog song drumming on our bones. Overhead, the stars wheeled around the sky in their own ancient dance, and Orion almost caught the Hare. We felt a sense of deep honor, to be able to sit with the frogs and share their songs. And when the cold started to seep into our bones, we took ourselves home to warm beds, leaving the frogs to the night...