Abstract
The Black-necked Crane (Grus nigricollis) is a rare species of crane that is endemic to China. The species was relatively little known outside China, having never been displayed even in a zoo until early 1958. In that year a couple of the birds were presented to the International Cranes Funds Organization.
Protected Species
The birds are classified as being in danger of extinction. It is now one of the most protected avian species in China.
Description
The Black-necked Crane stands over 40 inches (1 meter) in height and weighs approximately 11 to 18 lbs. (5 to 8 kg). The body feathers are smooth and are greyish white in color. The neck feathers are black and its long neck is muffled with a black-velour-scarf. The head is black with red on the top. A white spot is prominent in the area behind the golden eye. The wings, tail and legs are black. Its long beak, wax yellow in color, is extremely hard.
The birds live in the highland country and is the only species of crane to be found in such habitat.
The species is the last discovered of the 15 crane species known to exist (the first such crane spotting was reported in 1876). As of March 1986, the population of the Black-necked Crane in China totaled about 900.
The birds breed in marshland at elevations 3500 to 5000 meters above sea level. The Black-necked Crane can be found in the Qinghai-Tibet Plateau and north of the Sichuan Province from May to July. During the autumn season, the birds migrate to the lakes and swamps of southern Tibet, Yunnan Province, Sichuan Province and to the northwest of Guizhou Province. The birds remain in these areas until March in the following year.
Study of".Vintering Habits at Caohia Lake
Caohai Lake is an old, freshwater, highland lake. The lake bottom is 6000 feet (2170 meters) above sea level. The water area is approximately 17 sq. miles ( 45 sq km), with a maximum water depth of about 16 feet (5 meters). The water is so clear that one can see fish and shrimp. Large numbers of Wining Xi-fish, together with plenty of water and areas of lush grass, make this habitat ideal for these cranes.
The lake, called "Plateau Pearl;' almost disappeared. Over the past 30 years, massive tree harvesting in the nearby mountains resulted in serious soil erosion. Between 1958 and 1972, the lake silted up. Man-made dikes were built to reclaim 11-1/2 square miles (30 sq km) of the nearby land for farming. These impacts on the lake were disastrous. The lake nearly dried up. The important Wining Xifish died out and the lush growth of water grasses also failed. The decrease in habitat had a severe impact on water birds with few using the little remaining habitat. More importantly, the rare, Black-necked Cranes have been missing from the area ever since.
The Lake Is Restored
The disastrous effects of the tree harvesting, along with the disappearance of the lake and birdlife caused great concern. People joined together. Trees were planted on the slopes of the mountains. Irrigation facilities were created. Water was again being stored. In 1982 the water level of the lake had expanded to the point where there was some 9 1/2 sq miles (25 sq km) of water. Aquatic animal and plant resources developed rapidly. Water chestnuts, cattails, Li fish (carp), Ji fish (Crucian carp) and the important Wining Xifish could again be found through the entire lake area. Once again, flocks of migratory birds began to return to the lake for their winter resting and nesting period. At times thousands of birds can now be seen on the lake. Importantly, the Blacknecked Cranes returned to the lake. Counts indicate the number of the species is on the increase - 35 in 1975, 305 in the spring of 1984, and 350 in 1985. Today, as we drive to the lake, we can hear the call of the Black-necked Cranes. Now, the largest flock of Black-necked Cranes uses this lake as compared with any of several other wintering places that we know of.