I was not yet 30 when Ray entered my life and transformed my existence. We had little inkling then of how much his own life would be forever changed. In 1968, “Kalahari” was merely a word, but it would soon become hard reality. Ray once told me that for him the Kalahari is like my favorite place in Western Australia is for me (the Great Victoria Desert).
So-called “Barking” Geckos
Geckos are the most vocal of all lizards, and a Kalahari species has taken making noise to the extreme among geckos. In his blog, Wulf Haacke refers to “Memories of Barking Geckos,” noting that they do not call during cold weather. The common name “Barking,” however, is somewhat of a misnomer. These very vocal geckos (Ptenopus garrulus) issue a series of rapid clicks (some call it chirping) at nightfall in the Kalahari, chorusing like crickets or frogs. When hundreds or even thousands of these little lizards get going, they provide a wonderful nightly serenade — their choruses symbolize the Kalahari. Sometimes I have wondered if the strange clicking sounds in the language of the Khoi San Bushmen were inspired by the calls of these geckos.
Though abundant, Ptenopus were difficult to collect because they seldom strayed very far from their burrows. To catch them, Ray invented and perfected a neat “shovel trick”. To attract females, males sing from the mouths of their burrows with just their head, yellow neck, and foreparts out. If you approach slowly and silently, they will often hold their ground at this relatively safe spot. When you get within a couple of meters, hold your shovel out at arm’s length, then lunge suddenly, cutting off their retreat down their burrow. Occasionally, a gecko gets chopped in half, but more often than not this technique worked quite well.
One night when termites were swarming, and sending out their winged reproductive alates, we found dozens of Ptenopus out well away from their burrows feeding on the juicy soft-bodied insects. Some geckos were so stuffed that they could scarcely move, with their bellies full, their esophagus filled with termites, some even hanging out of their mouths! Such gluttony has its risks.
On an unusual overcast day when winged termites were swarming, and going on mating flights during daylight hours, Ptenopus, normally strictly nocturnal, were actually active in daytime. Several species of shrikes (small predatory birds) were capturing these geckos, saving them for future meals by pinning them up on thorny Acacia bushes as food caches. Dozens of crucified Ptenopus, many still alive, pinned up like Christmas tree ornaments, festooned nearly every thorny bush in that part of the Kalahari on that day.
Five years after our original Kalahari adventure was concluded, Ray, now a Harvard Ph. D. and inventor of evolutionary physiology, was a Miller postdoc at his old alma mater UC Berkeley. He called to say we’re going back under the auspices of a National Geographic Society grant to follow up our research on oogpister mimicry and foraging modes. When we returned to the Kalahari in 1975, Ray told me that, for him, the sound of the nightly chorus of barking geckos had become the Kalahari.
Eric R. Pianka