【摘要】 2004年7月和8月,通过样线调查、野外直接跟踪观察和瞬间取样的方法,首次对东大山自然保护区的岩羊种群进行了初步调查。东大山自然保护区夏季岩羊以小群为主,在观察到的720只岩羊中,719只组成了50个群,最大群82只,最小群2只,平均为14.38只,2～10只群占总群数的66%;雌性群占30%,雄性群占26%,混合群占44%,整个东大山的岩羊密度为34.8±19.2只/km2;岩羊的雌雄性比为1∶0.63,成年雌体、亚成体和幼体之比是1∶0.4∶0.24。研究结果表明,东大山近几年的狩猎对岩羊的种群并未造成大的影响。更多还原

【Abstract】 The population density and structure of the blue sheep(Pseudois nayaur)in Dongdashan Nature Reserve of Gansu Province were studied using a modified version of traditional focal and instantaneous sampling between 12 July and 26 August 2004.A total of 720 individuals were observed during the study period.The average herd size was 14.38 ± 15.83(n=50 herds)individuals.The largest herd was 82 individuals,and the smallest was 2 individuals.The blue sheep herds can be divided into three types:female herds(30%),male herds(26%)and mixed herds(44%).The number of 2~10 individual groups accounts for 66% of the total group number.The population density of blue sheep in Dongdashan was 34.8±19.2 individuals/km2.The ratio of adult females to males was 1∶0.63,and the ratio among adult females,subadults and young was 1∶0.40∶0.24.The local hunting in Dongdashan exerted no significant effects on the population of the blue sheep.更多还原