We have a winner. Photo by Stephanie Smith
Stephanie was doing her daily early morning run route through the wash on Wednesday when she came across two desert tortoises fighting, about a quarter-mile from our house. We’ve seen several tortoises in this area before, as chronicled on this blog, but this was the first time we’d seen two at once. What was going on here?
From “THE DESERT TORTOISE (Gopherus agassizii): A NATURAL HISTORY,” at the Arizona-Sonora Desert Museum:
Male combat is most intensive in spring and late summer in the Sonoran Desert. During these encounters, each male stands as high as possible, making short rushes toward his adversary while attempting to use the gular horn at the front of the plastron (undershell) to overturn the other or drive him away. An overturned tortoise can usually right itself using its head and a forelimb; if not, the tortoise may overheat and die under the desert sun. The desert tortoise produces a variety of sounds (hisses, grunts, pops, whoops, huhs, echs, bips, etc.) which seem to be the most important when vocalized to an unfamiliar tortoise.
A loose male dominance hierarchy is apparently established by aggression. Dominant males court and mate with females more often than other males.
Tortoises are a threatened species, and human contact with wild tortoises is strictly prohibited, so we watched from a distance, hoping to not affect the outcome—and that neither would seriously harm the other. Here’s some footage that Stephanie got of this rather bizarre clash of the tortoises…
Seconds after Stephanie stopped filming that segment, the tortoise on the right managed to flip over the tortoise on the left. Stephanie started filming again, as we tried to figure out what to do…
Eventually the victor wandered off, and the loser, after a few minutes struggling, was able to right himself, dust falling from this shell. How long had these guys been fighting? I saw this nearby, which looked like evidence of the scuffle having gone on for some time…
More photos from this battle: Clash of the Tortoises Part II
More about desert tortoises: digital-desert