Effects of farming practices in Tibet on wintering Black-necked Crane (Grus nigricollis) diet and food availability
农业耕作活动对西藏越冬黑颈鹤食性及食物可获得性的影响

We studied the availability of cereal grains as food resources for wintering Black necked Cranes in south central Tibet Autonomous Region, People's Republic of China during January 1996. Barley, spring wheat, and winter wheat were the three major crops. Fecal samples revealed that Black necked cranes fed extensively on waste cereal grain, especially wheat. Winter wheat seedlings comprised only a minor portion of the crane diet. Post harvest farming practices including plowing and livestock grazing influenced surface residue cover (seeds, leaves, stems, or roots) and waste cereal grain (kernels, spikelets, or chaffy bracts) available for cranes. Plowing buried most crop residue. In unplowed fields, proportion of waste grain residue cover was similar in harvested barley and harvested wheat fields. Harvested wheat produced the greatest density of surface waste grain. We recommend providing unplowed, harvested wheat and harvested barley fields near rivers and cultivating winter wheat closer to primary roads in order to maximize grain availability and minimize potential disturbance to wintering Black necked Cranes.