CHENGDU -- China's pioneer in ecological and biological research of giant pandas, Professor Hu Jinchu, also known affectionately as the "panda papa," died of illness at 94 on Thursday night.

The revered zoologist passed away at a hospital in Nanchong city, Southwest China's Sichuan province, according to China West Normal University.

Hu is internationally recognized as the founder of the ecological and biological research of giant pandas and is hailed as the "first man to study giant pandas in China."

He was appointed by the forestry department of Sichuan as the lead expert of a survey team for precious animal resources in 1974. At that time, China was just starting to explore the distribution, quantity and reproduction of such species, and his appointment was a significant milestone in this regard.

Undertaking the resource surveys in major giant panda habitats across Sichuan, Shaanxi and Gansu provinces was no small feat for Hu. The task was made even more challenging by the fact that giant pandas were incredibly elusive and difficult to spot in the wild, making it nearly impossible to trace their movements.

During his survey work, Hu made a significant breakthrough when he discovered that the feces of different pandas contained bamboo remnants of varying lengths, thicknesses and chewed states. By comparing these differences, he was able to gain valuable insight into the approximate age, population size and activity range of the pandas. This innovative method was later coined "Hu's method" of wild panda surveys and is still utilized to this day.

The survey team traveled 90,000 kilometers during its four-and-a-half years of arduous field research, and finally produced a survey report on precious animal resources in Sichuan province containing more than 200,000 words.