We use Florida sandhills, or another common species, to incubate the eggs. Indeed one of the major rationales for keeping an endangered species in captivity is the higher reproductive potential that's possible through these types of manipulations. The eastern flock summers in the northeast Russia and winters at Lake Poyang in eastern China. The western and central flocks summer in western Russia in the Ob River Valley. The western flock winters south of the Caspian Sea in Iran while the central flock winters in northern India near Bharatpur.
Siberian cranes are the third rarest of all cranes, and are arguably the most seriously endangered.
The eastern flock is the largest, with 3,000 birds wintering in China on the rich mudflats of Poyang Lake. This seasonal lake depends on annual flooding from the Yangtze River. Upstream, the proposed Three Gorges Dam would generate hydroelectric power, but would also control flooding and would affect the water levels at the Siberian's wintering area at Poyang Lake. Oil exploration and development pose a broad threat to this flock's breeding grounds in eastern Russian. The western flock has held steady at about 7-11 birds for the last decade.