Published on June 16th, 2013 | by James Ayre0
Cheetah Hunting Dynamics Revealed By New Study — First Direct Measurements Of Wild Cheetah Locomotion
The hunting and locomotion dynamics of wild cheetahs have had some new light shed on them as a result of new research from the Royal Veterinary College. The new research is the first to provide detailed direct measurements and data on the hunting and locomotion dynamics of the wild cheetah while still in its natural habitat.
The new work was done by utilizing a newly created GPS and motion sensing collar — designed by the researchers. By outfitting the cheetahs with the collars the researchers were able to obtain a great deal of data on the animal’s running and hunting dynamics. Some of the cheetahs used for the research were recorded running at speeds of up to 58 miles per hour.
Before this new research was done the only measurements ever taken of cheetah locomotion mechanics were made on captive animals running in a straight line while pursuing a lure. Most of these studies didn’t record the cheetahs as being very fast — often not even being faster than racing greyhounds. There had been no direct measurements taken of wild cheetahs running in their natural habitat — the estimates of their speed had been made entirely from direct observation or film, not direct measurement.
So, to remedy this, the researchers developed a “tracking collar equipped with a GPS module and electronic motion sensors (accelerometers, magnetometers, gyroscopes) capable of delivering processed position and velocity data and sensitive to the animal’s movements. The collar was powered by a combination of solar cells, rechargeable and non-rechargeable batteries.”
The Royal Veterinary College provides some details:
Collar software monitored the accelerometers to create activity summaries and detect the brief hunting events and adapted collar operation to battery voltages and time of day, meaning that researchers only captured data during a hunt. Overall, researchers recorded data from 367 runs by three female and two male adult cheetahs over 17 months. An episode of feeding after a run indicated hunting success, and was identified in the activity data by consistent, low-magnitude acceleration.
Data revealed that wild cheetah runs started with a period of acceleration, either from stationary or slow movement (presumably stalking) up to high speed. The cheetahs then decelerated and maneuvered before prey capture. About one-third of runs involved more than one period of sustained acceleration. In successful hunts, there was often a burst of accelerometer data after the speed returned to zero, interpreted as the cheetah subduing the prey — in this case mainly Impala, which made up 75% of their diet.
The average run distance was 173m. The longest runs recorded by each cheetah ranged from 407 to 559 m and the mean run frequency was 1.3 times per day, so, even if some hunts were missed, high speed locomotion only accounted for a small fraction of the 6,040-m average daily total distance covered by the cheetahs.
Using the data the researchers were able to clearly identify the factors that made up a ‘successful’ hunt. “Successful hunts involved greater deceleration on average, but there was no significant difference in peak acceleration, distance travelled, number of turns, or total turn angle. This indicates that outcome was determined in the final stages of a hunt rather than hunts being abandoned early to save energy or reduce risk of injury, and the higher deceleration values may reflect actual prey capture.”
“Grip and maneuverability, rather than top speed, were shown to be key to hunting success. Hunts involved considerable maneuvering, with maximum lateral (centripetal) accelerations often exceeding 13ms-2 at speeds less than 17ms-1 (polo horses achieve 6ms-2).”
For an idea of how the cheetahs matched up with other animals, and with people we think of as being fast: “The greatest acceleration and deceleration values were almost double values published for polo horses and exceeded the accelerations reported for greyhounds at the start of a race. The acceleration power for the cheetahs was four times higher than that achieved by Usain Bolt during his world record 100 meters run, about double that for racing greyhounds and more than three times higher than polo horses in competition.”
Professor Alan Wilson, stated: “Although the cheetah is recognised as the fastest land animal, very little is known about other aspects of its notable athleticism, particularly when hunting in the wild. Our technology allowed us to capture what to our knowledge is the first detailed locomotor information on the hunting dynamics of a large cursorial predator in its natural habitat and as a result we were able to record some of the highest measured values for lateral and forward acceleration, deceleration and body mass.
“In the future, equivalent data for other wild cursorial species would enhance what we know about natural speed, agility and endurance, and provide detailed information on ranging behaviour in the wild. For example, information on habitat selection by endangered species detailing where animals are commuting, hunting and resting would be informative when attempting to evaluate wildlife-protected areas.”
The new research was published June 13th in the journal Nature.