中文摘要：

2009年10月-2012年12月,采用样线调查法和问卷调查法对贺兰山国家级自然保护区内分布的白尾海雕Haliaeetus albicilla的越冬种群数量及时间、分布范围及生境类型进行了调查。根据最小种群数量评估法分析结果表明,在贺兰山地区的白尾海雕种群数量为9-14只,越冬时间为11月至次年2月,主要活动于悬崖峭壁或沟谷开阔地。

英文摘要：

A series of surveys on the population,distribution,habitat types and wintering period of white-tailed sea eagle（Haliaeetus albicilla） in Helan Mountain National Nature Reserve were conducted during 2009.10 to 2012.12.The surveys were carried out by line transect investigation and questionnaire surveys.According to the minimum population evaluation principle,the estimated number of white-tailed sea eagles in Helan Mountain was 9 ~ 14.These individuals were mainly inhabited in mountain cliffs or open valleys.The wintering time of white-tailed sea eagles in Helan Mountain was November to February.