In hot weather, elephants can lose up to 10% of their water in a single day, according to a new study.
This equates to 500 liters of water. It is the highest daily water loss of all land animals.
This finding doesn’t mean much to elephants in often “pampered” zoos, but shows that elephants living in the wild are in danger as their habitats warm and demand for water increases. while water is scarce, according to Baptiste Mulot, an elephant behavior researcher at ZooParc de Beauval – an animal park in France.
Elephants are inherently threatened, dehydration from hot weather can lead to lower birth rates, loss of milk for young elephants and death from dehydration. Elephants drink hundreds of gallons of water a day, but it’s unclear how climate change will alter their water needs.
So in the new study, researchers led by conservation biologist Corinne Kendall examined five African savanna elephants (Loxodonta africana) at the North Carolina Zoo. In three years, the team fed the elephants six times with deuterium – a heavier version of hydrogen, harmless, soluble in water and traceable in the liquid where the elephant was released. Scientists regularly took blood samples for 10 days after feeding the elephants with deuterium to see how much was left each time, thus calculating the rate of excretion of water in the elephant’s body.
The results were “astounding,” Kendall said. At cool temperatures (between 6 ° C and 14 ° C), males lose an average of 325 liters of water per day. But at around 24 ° C, they lose an average of 427 liters, and sometimes go up to 516 liters, the team wrote in the Royal Society Open Science.
400-500 liters of such water is equivalent to 10% of the elephant’s total body water – or up to 7.5% of body mass. An elephant has lost almost 9% of its body mass in a single day, says Rebecca Rimbach, an ecological biophysiologist at Duke University. However, since elephants continually replenish lost fluids through drinking, eating, and metabolizing, the elephant’s actual daily water loss will be less. In general, elephants should drink water at least every two to three days to avoid “dangerously high levels of dehydration,” Rimbach said.
“It’s surprising if you remember that these are animals that have adapted to life in the African savannas [poor water environments],” Kendall says.
Horses in hot environments can lose 40 liters of water per day – around 6% of their body mass – and humans typically consume around 3 to 5 liters – around 5% of their body mass, however can almost double with activity vigorous and sweating.
Worryingly, as global temperatures rise more and more, elephants will need to drink more water. But as the temperature rises, the water becomes scarce, water holes dry up, and water-rich plants become more difficult to find. Study co-author Erin Ivory, behaviorist at the North Carolina Zoo, said this double effect could also exacerbate the conflict between wild elephants and human populations, when elephants attack the season. Memories or destruction of underground infrastructure, violent clashes that can be fatal to both humans and elephants.
