Abstract: We analyzed the daily wintering behavior patterns and their affecting factors in common crane (Grus grus) inhabiting paddy field near Poyang Lake from October 2018 to March 2019, using focal sampling methods. Foraging (77.45%), vigilance (11.17%), and grooming (7.82%) were the main behaviors of cranes, with the predominant patterns being: foraging vigilance foraging and foraging grooming foraging. The time budget and duration spent for foraging by juvenile cranes was significantly higher than that of adult cranes (P<0.01). This is probably due to lower feeding efficiency in young cranes and longer total foraging time and individual foraging duration. The vigilance behavior of adult cranes (P<0.01) was significantly greater than that of juvenile cranes, with no significant difference in the duration of vigilance behavior betweenjuvenile and adult individuals. The frequency and time budget of vigilance in adult cranes during foraging intervals were significantly greater than that of juvenile cranes (P<0.05). This result indicates that adult cranes protected the safety of juvenile cranes by increasing the number of vigilance scans. The duration and time budget of foraging behaviors increased throughout the overwintering period. Locomotion was increased throughout the wintering period, which was related to the availability of food resources. Reduced intensities of human activities, such as grazing domestic ducks, would decrease foraging difficulty for cranes. There were significant differences in locomotion behavior among different crane families and during foraging intervals, which may be related to the differences of food resources. In terms of the activity rhythms, foraging behavior was generally at a high level during the daytime, with small peaks at 10:00-10:59, 12:00-12:59, and 16:00-16:59. Vigilance behavior remained at a stable level. A peak in grooming behavior occurred after a peak of foraging behavior because cranes groom after becoming fatigued from foraging. The behavioral rhythm of juvenile cranes was different from that of adults, with the foraging behavior of adults being more rhythmical and that of juvenile cranes is more random. This is related to the lack of foraging experience. The peak of vigilance behavior in young cranes occurred in the trough of such behavior in adult cranes, which may relate to the consistence of the vigilance in the whole family group.

Key words: oxidase activity., Pinus elliottii, red soil, nitrogen addition, hydrolase activity