At Qianhe Island Tourist Scenic Area in Zhaodong City, northeast China's Heilongjiang Province, around 80,000 migratory birds have entered their peak breeding season. To ease competition for nesting space, around 100 multi-tier artificial nests have been built in the scenic area, with upper levels for oriental white storks, middle levels for cormorants and lower levels for smaller waterbirds. Located in the Songhua River basin, the area is home to more than 140 species of migratory birds and has