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Although the cheetah is recognised as the fastest land animal, little is known about other aspects of its notable athleticism, particularly when hunting in the wild. Here we describe and use a new tracking collar of our own design, containing a combination of Global Positioning System (GPS) and inertial measurement units, to capture the locomotor dynamics and outcome of 367 predominantly hunting runs of five wild cheetahs in Botswana. A remarkable top speed of 25.9ms^sup -1^ (58 m.p.h. or 93kmh^sup -1^) was recorded, but most cheetah hunts involved only moderate speeds. We recorded some of the highest measured values for lateral and forward acceleration, deceleration and bodymass-specific power for any terrestrial mammal. To our knowledge, this is the first detailed locomotor information on the hunting dynamics of a large cursorial predator in its natural habitat.
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Measurements of instantaneous speed, acceleration and manoeuvring during athletic competition or hunting are rare1-4, even for humans, horses and dogs, the most studied species. The cheetah (Acinonyx jubatus) is acknowledged as the ultimate cursorial predator, and its published5 top speed of 29ms21 is considerably faster than racing speeds for greyhounds2 (18ms21), horses1 (19ms21) or humans (12m s21; see 'Analysis of Bolt's 100m' at http://berlin.iaaf.org/ records/biomechanics/index.html). Quantitative measurements of cheetah locomotionmechanics have only beenmadeon captive animals chasing a lure in a straight line, with few studies eliciting speeds faster than racing greyhounds6,7. For wild cheetahs, estimates of speed and track have been made from direct observation or film only, and are limited to open habitat8,9 and daylight hours.
Tracking collar design
To collect free-ranging locomotion data on wild cheetahs during hunting in their normal environment, we designed and built a tracking collar similar in size and weight to a conventional wildlife collar10,11 (Fig. 1a; mass of 340 g), equipped with a GPS module capable of delivering processed position and velocity data, and raw pseudo-range, phase and Doppler data for individual satellite signals at 5 Hz, and an inertial measurement unit (IMU) consisting of triaxial microelectromechanical systems (MEMS) accelerometers, gyroscopes and magnetometers (Methods). The collar was powered by a rechargeable battery charged from solar cells, plus a non-rechargeable auxiliary battery. Data download and configuration upload was via radio. Collar software monitored the accelerometers to create activity...