中文摘要：

红隼和黄爪隼繁殖分布区重叠,二者的外部特征十分相似,但行为却很不相同,包括是否远途迁徙、繁殖过程、食物与食性等。2006年5~6月和2010~2011年春夏及2012年5~7月,采用焦点观察法和路线调查法,对新疆北部几个繁殖区的黄爪隼和红隼的活动规律、栖息地选择、相互距离、繁殖习性、食物组成展开调查。虽然它们的生活环境比较接近,两者巢间距最近约30 m,但取食生态位却是不同的,红隼更喜欢捕捉沙鼠、小鸟、麻蜥或沙蜥等脊椎动物（占84.8%）,而黄爪隼则以采食直翅目昆虫、蜈蚣等无脊椎动物为主（占95.3%）。二者每小时捕食育雏频次也显著不同。在中国,黄爪隼可能是一个＂入侵＂的或＂东扩＂物种,此消彼长,漂泊成性,营巢地不固定,近10年种群数量有增加的趋势。

英文摘要：

The genetic relationship between lesser kestrel（Falco naumanni） and common kestrel（Falco tinnunculus） are very close.Although the external characteristics of them are similar,the behaviors including migratory,process of breeding,food and habits of feeding in the nests are very different.The activity patterns,habitat selection,species distance,breeding habits,lists of food of both species were investigated in several breeding areas of the northern Xinjiang using focus observation and route survey during May to June of 2006,spring and summer of 2010 ~ 2011 and May to July of 2012.The results showed that the living and breeding environments of lesser kestrel and common kestrel were relative close,and the distance between their nests was about 30 m.However,their feeding niches were different.Common kestrels preferred to capture the gerbils,mice,small finches,common lizards,sand reptiles and other vertebrates（84.8%）,whereas the lesser kestrel like the species of Orthoptera（e.g.locusts）,centipedes and other invertebrates（95.3%）.Moreover,the predation rate and feeding frequency were significantly different.In conclusion,the lesser kestrel may be an invasive or the species experienced a rapid eastward expansion in China and their nesting sites are unfixed,and the population size in Xinjiang tends to increase during the last decade.