The Desert Responds to its First Rain: Part 1

The thunderstorm came in just after sunset. Temporarily blinded by a nearby bolt of lightning, I can feel the thunder in my chest. Quickly the storm moves on and the air is filled with a new sound: the calling of thousands of toads. I am standing outside a room at the Posada, with Matt and Richard, two American conservationists spending the night, and sharing their beer with me.

We wander down to a newly-created pond, drawn by the mating calls of Couch’s spadefoot toads, Scaphiopus couchii . Already they are pairing up, the males embracing the females from behind. Soon eggs will be laid, fertilised and left to fend for themselves in a pond which will completely dry up in less than two weeks.

I remember the calls of frogs and toads from my childhood in Northern Ontario. Each species would have its own season, throughout the spring and summer months, and I could hear the calls from my bedroom window.

So imagine my surprise when the very next night, I went down to the pond to listen to the toads and was met with silence. Northern frogs time their mating by temperature and day-length, and call for weeks before all are mated. But in the desert, the ponds dry up, and so the tadpoles have a short time to grow and transform into adult toads.

The mating was over that first night, and already the eggs were hatching into tiny tadpoles. The adult toads have a few days to feed before the ground starts to harden, and they burrow in again to await the next rains.