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201315Aug21:12

Cheetah myth busted, they do not overheat during hunt

published 15 August 2013 | modified 28 June 2014
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Dr Robyn Hetem and her colleagues from the Brain Function Research Group at the University of the Witwatersrand (Wits) found that cheetah body temperature did not increase during the sprint while hunting. Their findings have been published on 24 July in the journal Biology Letters.

Cheetahs runningFor superb athletes, cheetah are surprisingly poor hunters with up to 60% of hunts ending in failure. In a race over 100m, a cheetah would beat Usain Bolt by 60 meters, and easily could outsprint any antelope. But they often give up the sprint when within easy reach of their prey.

Nearly forty years ago, Harvard researchers suggested that cheetah abandon hunts because they overheat. They ran cheetah on a treadmill and found that cheetah stopped running when their body temperature reached 40.5°C. Extending their finding to real hunts, the researchers concluded that cheetah could only sprint so far before getting too hot to move. The problem was that the speed that the treadmill could reach was nowhere near that of a real hunt. Nevertheless, since then people thought that the incredible speed cheetah can develop comes at a price, an overheated 'engine' that makes them abandon the hunt. This appears now to be a myth.

So what happens in a real hunt? Answering that question had to wait until researchers could measure body temperature of hunting cheetahs. Researchers from the Brain Function Research Group at Wits, working with Professor Shane Maloney of the University of Western Australia, developed the technology needed.

How do cheetah reach the speeds that make it the world's fastest land mammal:

 

“But that wasn’t enough,” said Professor Andrea Fuller, the Group’s Director. “We needed conservators who were committed to advancing cheetah research.” The Group found those conservators at the AfriCat Foundation, based at the Okonjima Nature Reserve in Namibia.

The AfriCat Foundation runs a cheetah rehabilitation programme to give some of their captive cheetahs an opportunity to return to their natural environment. Although hunting in carnivores is instinctive, many of the cheetahs at AfriCat lack experience due to being orphaned or removed from the wild at an early age. This inexperience, as well as their conditioning to captivity, makes these animals unsuitable for release on farmland. The cheetahs (usually a coalition of brothers and sister) are fitted with radio-collars before their release into the camp so that their welfare and progress can be closely monitored.

 

Veterinarians equipped six cheetah with body temperature and activity sensors. The researchers observed a number of hunts and their data revealed that, contrary to initial expectations, cheetah body temperature did not increase during the sprint.

Mysteriously though, cheetah temperatures did rise after the sprint was finished, more so if the hunt had been successful despite the cheetah sprinting just as hard when they got the prey as when they didn’t. What were the cheetah doing then? Typically the cheetah were resting next to their prey. Because the body temperature rise started before the first mouthful, eating could not have caused the mysterious late rise in body temperature.

How beautiful it looks, shows this ultra slo-mo video of a cheetah running:


This video shows the grace and force of a cheetah running at full speed. Watch the length of the cheetah’s stride (up to 8 metre).

The researchers propose that the stress of guarding the prey from more dominant carnivores, such as leopards, may account for the increase in body temperature following successful hunts. Research veterinarian, Dr Leith Meyer, confirmed that he has seen similar increases in antelope body temperature when they are stressed.

So cheetah do abandon hunts but not because they overheat, and a theory that had been in natural-history books for nearly forty years is a myth.

 

(Source: Wits University media release, 30.07.2013)

UN Biodiversity decade

Goal: 7000 tigers in the wild

Tiger range countries map

 

"Tiger map" (CC BY 2.5) by Sanderson et al., 2006.

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