HARBIN - Ornithologists from China and Russia have observed six species of endangered birds in a joint monitoring initiative conducted in a natural wetland reserve in northeast China's Heilongjiang province, the reserve authorities said Wednesday.

The seven-day monitoring project starting September 28 recorded 125 species of birds in the reserve, the Xingkai Lake Natural Reserve said in a statement.

Scientists have found black woodpeckers, sharp-tailed sandpipers, rock pigeons, ashy minivets and thick-billed warblers that had never been seen in the reserve before, according to the statement.

Large flocks of other rare birds were also observed, setting a record number for recent years.

Wu Fule, deputy chief of the reserve's administrative bureau, said millions of migratory birds flock back to the reserve in autumn, creating good opportunities for bird watching.

"The monitoring project is a successful one and will help in the protection of, and research on birds in the region," said Wu, adding that China will further cooperate with Russia to explore new methods for bird protection.

Established in 1997, the Xingkai Lake Natural Reserve crosses the Sino-Russian border and covers 330,000 hectares, with two-thirds in China.