Recent reports suggest that the giant pachyderms are now heading back to their old stomping ground, but Zhou was not surprised that they had become mobile.

"In my opinion, migration is a common activity for wild animals, whose nature is to look for a comfortable place to stay and more food to feed their offspring. Their journey has made people think again about better ways of maintaining good relations between animals and humans," he said.

After tracking animals over many decades, Zhou believes that a balanced environment must involve moderate human activity.

"Sometimes, excessive forest protection can be bad for the animals. Thick cover limits the growth of the grasses and shrubs that feed herbivores, which in turn provide food for carnivores," he said.

He believes that wild elephants need homes with diverse plant life rather than tall trees.

"To solve such conflicts, I think a national park should be established to help formulate a long-term plan to restore the elephants' habitat and build harmonious relations between these old giants and humans," he said.

Shi Wenzhi contributed to this story.