Behavioral Patterns of Baer's Pochard under Different Water Levels During Overwintering
From November to December 2018,we used the fixed-point and scanning sampling methods to study the day-time behavioral activity rhythms and time allocation of Baer's pochard(Aythya baeri)under different water levels during the overwintering period.The results showed that:(1)Differences existed among the temporal distribution of seven types of behaviors of A.baeri under different water levels.A.baeri was mostly resting and foraging at shallow waters,and was rest-ing,locomotion,and foraging behaviors at moderate level of water areas,but was locomotion,flying,and foraging at deep waters.Time allocation for foraging and resting behaviors decreased with increasing water level overall,while time alloca-tion for locomotion,flying,and social behaviors increased with increasing water level.And time allocation for maintaining behaviors was significantly lower at shallow water than that at moderate to deep water levels,but the difference in between moderate and deep water was not significant.(2)All behavioral rhythms of A.baeri during the overwintering under different water levels varied.In terms of foraging behavior,A.baeri at the deep and moderate water levels showed a highly similar pattern,whereas a contrasting pattern was revealed only in the morning and evening at the shallow water areas.There was an increasing trend of resting behavior at deep water levels,and no peaks or troughs overall,while the fluctuations in the shallow water level area were greater than in the deep and moderate water level,and increased significantly after 13:00-14:00.The behavioral rhythms of maintaining behavior of A.baeri at moderate and deep water levels were opposite in the occur-rence of peaks,and was an"S"shape at the shallow water.And maintaining behavior was largely reduced at all water lev-els after 15:00-17:00.For locomotion behavior,the moderate water level was used as a transition,with peaks and val-leys interspersed with deep and shallow water levels.Overall,fluctuations in locomotion and maintaining behaviors were greater at the deep water than at the moderate water and the shallow water;peaks and valleys for foraging roughly over-lapped with peaks and valleys for locomotion at all three water levels,and foraging valleys overlapped with their resting peaks at the shallow water level.A.baeri preferred to be at shallow water than at relatively deep waters during overwinter-ing.Therefore it is recommended that the relevant management authorities manage water levels in the wintering area of A.baeri by increasing the areas of shallow water and reducing human disturbances.
Behavior rhythmBehavior time allocationWater level environmentOverwintering Aythya baeriMinquan Wetland Park
NETL
NSTL
万方数据
