Scaphiopus couchii digs backwards into sandy desert soil with the black keratinous spade on each hind foot, and remains there through the dry months in a torpid state, tolerating substantial water loss and accumulating urea to draw moisture from the surrounding soil. Emergence is triggered by heavy rain, and the cue appears to include the low-frequency vibration of rainfall or thunder rather than moisture alone.
Once out, the schedule is brutal. Adults call, mate and lay the same night in whatever pool has formed. Eggs can hatch within about 24 to 48 hours, and larval development in some spadefoot species is completed in under two weeks, among the fastest known for any frog. Tadpoles that cannot finish before the pool dries die.
Related spadefoots add another twist: in Spea species, tadpoles can develop into either an omnivorous form or a broad-headed carnivorous morph that eats shrimp and other tadpoles, with the switch depending on diet and crowding. Adults of Couch's spadefoot may feed for only a few weeks a year, taking most of their annual energy in a handful of nights of termite and beetle swarms.