Time budgets of Tibetan eared pheasants during the non-breeding season in an alpine scrub habitat

摘要

Time allocations of the group-living Tibetan eared pheasants Crossoptilon harmani with and without supplementary food were investigated by full-day sampling from winter through spring in an alpine scrub zone,south Tibet.At a flock scale,both the different food-supply flocks displayed similar daily patterns of activity,foraging in the morning and evening,and resting around midday.In terms of individual activity,either foraging or resting was highly synchronous with the flock's.Non-provisioned birds spent more time feeding and less resting in midwinter than in late autumn.In early spring as climates became warmer and day longer,however,non-provisioned birds did not decrease their feeding efforts significantly but the provisioned birds did.Across the non-breeding seasons,the provisioned birds(relying on nutrition-rich artificial food)devoted less time to feeding and more to resting than did the non-provisioned ones(relying on nutrition-poor plant roots).Multivariate analysis showed increased food supply and ambient temperature resulted in a reduced foraging effort.However,the fact that the non-provisioned birds can save daily time for resting even in the cold short-day length mid-winter indicated that they faced no energetic constraint.Thus,protecting shelter vegetation rather than providing extra food is suggested to be important for long-term survival of the endangered galliform birds.