A new study finds that wild African elephants prefer to stay in protected areas like national parks, rather than spend time outside the parks.

Researchers involved in the study also found that the stress levels of the elephants are higher when they leave safer places for open areas.

For their study, scientists studied the African elephants (Loxodonta africana) in order to determine their welfare inside the well-protected Serengeti National Park in Tanzania and in the adjoining areas of Grumeti Game Reserve and Ikoma Open Area, where human disturbance is higher.

They examined elephant dung and found that the animals living outside the national park have higher levels of the stress hormone gluccorticoid.

The researchers also noticed that more elephants prefer to stay inside the park rather than outside the park. Not a single male elephant was found living in an open area. This suggests that the elephants know which areas are safer and try to avoid interaction with humans.

While the Serengeti National Park protects the elephants from threats like illegal hunting and habitat disturbance, the areas surrounding the park are not protected with any fences, placing them at a higher risk. Scientists suggest that the elephants may have learned to link humans and vehicles with the hunting activity that occurs outside the Serengeti National Park, reports BBC.

"Elephants probably remember where they are, and that bad experiences stress them," Dr. Eivin Roskaft, from the Norwegian University of Science and Technology in Trondheim, told BBC Nature.

"I think elephants know where they are safe or not. However, sometimes they also are tempted by nice food outside the park which attracts them to such areas."

Researchers hope their study will shed light on how protected parks could improve elephants' welfare.

African elephants are the largest animals roaming the Earth. They are widely distributed in different habitats ranging from tropical forests to flooded grasslands and savannahs. According to the World Wildlife Fund (WWF) conservation group, the status of the African elephants is listed as "Vulnerable".

The findings of the study are detailed in the African Journal of Ecology.