"Some birds are very alert, which brings difficulty to our work and we need to use some camouflage and spend more time waiting for the perfect photograph," said Liu.

The observation was conducted using line-intersect sampling methods, with 10 different sample lines at Mount Tai. If a bird was sighted at any of the lines, then it would be included in the observation data.

Liu set out the practicalities of the observation, saying that the observation would run from 5:30 to 9:30 each morning, and vital statistics about the bird would be recorded.

To ensure the accuracy of the data, amateur bird enthusiasts taking part in the observation had to abide by the strict rules of the project.

"During the observation, we found five species of national second class protected birds and five new recorded bird species in Shandong," Liu said.

Eurasian eagle owl (Budo budo), one of the national second class protected birds and resident species at Mount Tai. [Photo/Liu Zhaorui]

Greater necklaced laughingthrush (Garrulax pectoralis), one of the resident species at Mount Tai. [Photo/Sun Jialing]

Little owl (Athene noctua), one of the national second class protected birds and resident species at Mount Tai. [Photo/Zhang Peidong]

Naumann's thrush (Turdus naumanni), one of the winter visitors at Mount Tai. [Photo/Liu Zhaorui]