惊飞距离--杭州常见鸟类对人为侵扰的适应性

惊飞距离是指人在鸟类惊飞之前能接近鸟类的距离，反映了鸟类对人为侵扰的适应程度。2002年9月至2003年1月，在杭州6个区的调查中共见到42种鸟类，以其中的9种优势种兼广布种为研究对象分析了鸟类沿侵扰梯度惊飞距离的变化及影响惊飞距离的主要因子。根据植被类型、建筑比例、干扰因素等差异，将栖息地分为5类：建筑区，城市园林，西部山区，水荡，农田。选取体重、活动高度、观测点可视度、引人注目程度、迁徙状态作为探讨惊飞距离的5个变量。研究结果表明：①不同栖息地的人为侵扰程度有极显著差异：建筑区的人为侵扰程度与城市园林有显著差异，西部山区、农田和水荡之间无显著差异。②在不同栖息地中，惊飞距离具有显著差异；随着人为侵扰程度的提高，同种鸟类在不同栖息地中的惊飞距离呈减小趋势。③鸟类对人为侵扰的惊飞距离与选取变量问的关系显著：体形大小、观测点可视度与惊飞距离呈显著正相关，活动高度与惊飞距离呈显著负相关，而引人注目性与惊飞距离不相关。说明多数鸟类对人为侵扰已有了一定的适应性；体形较大、在植被稀疏的栖息地中以及靠近地面活动的鸟类惊飞距离较大，对人为侵扰的适应性较差。

Flush Distance:Bird Tolerance to Human Intrusion in Hangzhou

Flush distance,how close one can get to a bird before it flushes,reflects the adaptation of birds to human intrusion.A larger flush distance indicates a lower adaptation to human intrusion.To examine the patterns of the adaptation of birds to human intrusion and its influencing factors,9 dominant and widely-distributed species were selected among 42 species surveyed in Hangzhou,China from September 2002 to January 2003.Based on the differences in vegetation type,building index and disturbance degree,habitats were divided into 5 categories:building areas,urban woodlots,western mountains,ponds and farmlands.Four variables reflecting biological traits of birds (body size,activity height,migratory status,conspicuousness) and one habitat variable (visibility of observation point) were selected to examine their influence on flush distance.We found that:1)The degrees of human intrusions in 5 habitats were significantly different.2)There were significant differences in the flush distance of 9 species among different habitats.Generally,the flush distance was negatively associated with human intrusion.3)The analysis of bivariate correlation showed that flush distance was positively associated with body size and the visibility of observation point,but it was negatively associated with activity height.However,there was no significant association between the flush distance and the conspicuousness of birds.Our results indicated that most species had adapted to human intrusions to some extent,and that the birds with larger body,or those occurred in the habitats with higher visibility or closer to the ground had relatively lower adaptation to human intrusions.