Friday, August 10, 2018

The Tawny Jewel of the Savanna

Thomson’s gazelles are probably the Mara’s most underappreciated antelope. They’re small, they’re everywhere, and to most visitors to the Mara they seem relatively mundane. As a result, most tourists tend to drive past Thomson’s gazelles without a second thought. However, there is more than meets the eye when it comes to the overlooked “tommy”.
            The Thomson’s gazelle is one of the most successful species in the antelope family (Estes, 2012), due to its ability to not only graze but also browse on shrubs and bushes when grass becomes scarce. According to Estes, the tommy also has a convertible digestive system that allows it to switch from grazing to browsing (and vice versa) without any difficulty.
            Because of their small size and abundance, tommies are vulnerable to predation from most of the Mara’s carnivores – from eagles to lions. While the tommy can run up to 80 kilometers an hour (compared to 40-60kph for a spotted hyena), it cannot keep this top speed for long. Depending on the danger presented by the predator, tommies alter their avoidance distance. It can be as short as 5 meters for jackals and as long as 1500 meters for endurance predators such as wild dogs and hyenas (Estes, 2012).

            Finally, aside from only needing 1 hour of sleep a day, which alone is rather impressive, my favorite fact about the tommy has to do with its tail. Many of the ungulates in the Mara use their tails to swipe away pesky biting flies, and these motions are usually quick and random. However, upon my first visit to East Africa I noticed that tommies repeatedly swing their tails back and forth on a fairly regular basis – yet few of them were covered in biting flies. After doing some digging, I learned that the wags of the tommy tail are not to keep away flies, but to signal to other tommies. The rump of the tommy is white, which contrasts well against its black tail. The movement of the black tail over the white rump can be seen from some ways away and communicates to other tommies that the wagger of the tail is another tommy (Estes, 2012). This motion is constant and repetitive, much like a dog wagging its tail. This probably helps tommies come together after grazing or may help solo tommies find friendly herds. Because of this, these antelopes have earned the nickname of “savanna puppies” (given to them by yours truly), a special place in my heart, and hopefully now a special place in yours!

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