藏原羚集群行为的初步研究

Grouping behavior of the Tibetan gazelle (Procapra picticaudata) in Hoh Xil region, China

20 0 2年 10月至 2 0 0 3年 12月 ,在可可西里对藏原羚 (Procaprapicticaudata)的集群行为进行了初步研究。将其集群划分为雌性群、雄性群、母仔群、雌雄混群和独羚 5种类型。共统计藏原羚 92 4群次 ,计 36 4 3只次。其中 ,雌性群 5 2 5群次 ,占 5 6 .8% ,为最多的集群类型 ;其余为独羚 (2 6 .1% )、雄性群 (11.0 % )、母仔群 (3.0 % )和雌雄混群 (3.0 % )。不同大小集群的比例亦有极显著差异 ,其中 2 - 10只的集群占 70 .0 % ,独羚占 2 6 .1% ,其余为 3.9% ;最大集群为 17只。另外 ,选择 2 - 8只的集群的个体数占 72 .9% ,选择 8只以上集群的个体数为 2 0 .5 % ,独羚仅占 6 .6 % ,选择不同大小集群的个体数的差异也极为显著 (P <0 .0 0 1)。除独羚外 ,其余 4种集群类型的集群大小存在极显著差异。独羚作为一种特殊的集群类型 ,其雄性个体的比例占到 6 8.1% ,这说明雄性个体比雌性更容易形成独羚。总体而言 ,藏原羚的集群以雌性群为主 ,最适集群大小为 2 -

The Tibetan gazelle (Procapra picticaudata) is an endangered species inhabiting the Qinghai-Tibetan Plateau. From October 2002 to December 2003, we observed 924 groups (3643 individuals) of Tibetan gazelles in Hoh Xil region. These groups could be classified into five types. Female groups (525) were the major type, accounting for 56.8%. Solitary gazelle (a special group type), male groups, mother-calf groups and mixed groups made up 26.1%, 11.0%, 3.0% and 3.0%, respectively. Group size ranged from one to 17 individuals. Groups of 2-10 individuals, solitary gazelle groups and larger groups (>10 individuals) accounted for 70.0%, 26.1% and 3.9%, respectively. 72.9% of gazelles were observed in group with sizes of 2-8 individuals, while 20.5% were observed in group sizes > 8 and 6.6% were solitary. A chi-square test showed that the frequencies of individuals in different group sizes were significantly different (P<0.001). Group sizes varied significantly among different group types (Kruskal-Wallis H test, P<0.001). There were significantly more males (68.1%) than females (P<0.001) in solitary groups. To sum up, female group was the main group type of Tibetan gazelles, and the optimal group size was 2-8 individuals.