Hooded crane Grus monacha is listed as an endangered species by China red data book, and was listed as a vulnerable species by IUCN, and listed AppendixⅠof CITES. The population of Hooded Crane is about 9 500 individuals worldwide and breeding is limited to remote eastern Siberia in Russia and Xiaoxing’an mountains marsh in China. The species winters in in southern Japan, and the south coastline of Korea, and middle-lower reaches of Yangtze River in China. Because little is known about their breeding biology, we conducted this study to provide a scientific basis of future protection in China. We conducted our study in the Xiaoxing’an mountains Zhanhe valley of Heilongjiang province between spring in 2003 and spring in 2004. We located nests erected a tent 10-30 meters from the nest. We observed Hooded Crane or the nest from the tent and documented behaviour by video and still camera throughout the day. When migration justly or moving in breeding site of hooded crane, we had taken investigation and recording by binoculars and long-focus camera and photo-camera，and during sorted out the records, we checked continually and made accurateness just by video information and photos.
The study revealed that hooded crane migrated to the breeding site in early April yearly, mated in middle April, and laid eggs in late April or early May. The average egg was 93.4×58.4 mm in size and weighed 159.4 g. Male and female of hooded crane hatched together after incubating 30.5 days. Hooded crane build nests in the marshy forests or small swamp, and the average nest was 900×900 mm in size with no obvious interior diameter. The nest was 130-180 mm above water and the water depth around the nest was 120-300 mm. Adult hooded crane fed chicks with earthworms and polliwogs, etc. Comparing the habitats of hooded crane nest with Russia, breeding of hooded crane in Zhanhe where there are more trees and greater concealment. We recorded large-billed crow Corvus macrorhynchos, black kite Milvus migrans, golden eagle Aquila chrysaetos that threatened the hooded crane. During the hatching period, hooded crane showed anxiousness to great spotted woodpecker Picoides major. Breeding of hooded crane in Xiaoxing’an mountains mainly fed on Heilongjiang brown frog Rane amurensis, Siberian salamander Hynobius keyserlingii, leech, loach Misgurnus mohoity， predaceous diving beetle Cybister spp., perch sleeper Percottus glehni，lake minnow Phoxinus percnurus and wheat seeds [Acta Zoologica Sinica 51（5）：903–908，2005].