宁夏贺兰山岩羊春季种群生态研究

Studies on the Spring Population Ecology of Blue Sheep of Helan Mountain in Ningxia

以实体观测垂距法对贺兰山春季岩羊种群数量、性别、年龄结构等进行了调查,结果显示,2005年春季岩羊种群密度为（13.13±2.27）只/km^2,总数量为（11 161±1 930）只,1997—2005年春季岩羊数量累计增长了50.48%,年平均增长率为6.01%,比1983—1997年的年平均增长率13%有明显降低.2005年春季成体与幼体个数比为3.44∶1,成体中雌性与雄性个数比为1∶1.04,群体中混合群占59.6%,雄性群占19.3%,雌性群占21.1%,独羊占8.2%,群体大小范围为2～28只,平均为6.6只.

In spring of 2005,the population density of blue sheep（Pseudois nayaur） of Helan Mountain in Ningxia is（13.13±2.27）/km2,their total number is 11 161±1 930,the increasing rate of their number adds up to 50.48% from 1997 to the spring of 2005,the average rate of increasing is 6.01%,lower than the average rate（13%） of 14 years during 1983 to 1997.The ratio of adult to young is 3.44∶1,the ratio of the adult female to adult male is 1∶1.04.In blue sheep colony,the mixed group was 59.6%,the male group was 19.3%,the female group was 21.1%,the solitary blue sheep was 8.2%,the solitary blue sheep was mainly adult male.The range of the number of groups was from 2 to 28,and the average number was 6.6.