For at least 30 years, scientists have believed that cheetahs fail to catch their prey more often than other big cats because they overheat at high speeds. But researchers in Namibia who implanted sensors in six cheetahs tell a different story. Even when one of the study animals came close to the maximum chase distance ever reported for a cheetah, his body temperature did not exceed that of his regular 24-hour average. After the hunt, cheetahs’ temperatures rose slightly, more when the hunt was successful than when it was not. The researchers attribute this temperature increase to the stress of protecting a kill from other predators.
Hunting cheetah reportedly store metabolic heat during the chase and abandon chases because they overheat. Using biologging to remotely measure the body temperature (every minute) and locomotor activity (every 5 min) of four free-living cheetah, hunting spontaneously, we found that cheetah abandoned hunts, but not because they overheated. Body temperature averaged 38.4°C when the chase was terminated. Storage of metabolic heat did not compromise hunts. The increase in body temperature following a successful hunt was double that of an unsuccessful hunt (1.3°C ± 0.2°C versus 0.5°C ± 0.1°C), even though the level of activity during the hunts was similar. We propose that the increase in body temperature following a successful hunt is a stress hyperthermia, rather than an exercise-induced hyperthermia.