四川省石渠县藏原羚秋季取食行为特征

20 0 3年 8～ 10月 ,用固定观察和扫描取样法对四川石渠县藏原羚 (Procaprapicticaudata)的取食行为进行了研究。设置 4 0个 2 0m× 2 0m的样地 ,测量藏原羚的 13个取食生境因子。利用单个样本的Kolmogorov Smirnovtest检验 ,呈正态分布的用参数检验 ,否则用非参数检验。结果显示 :(1)藏原羚主要以集群的形式取食 ,集群大小为 6 8头 (n =4 9) ,最大群为 34头 ;雄性群具有小集群的倾向 (即除存在独雄外 ,2～ 3头一群的群体数占 33 33% ,n =9) ,母子群也以小集群为主 ,两母子为一群的集群占 5 3% (n =15 ) ,但是没有发现<4头的雌性群。 (2 )藏原羚的取食时间以晨昏为主 ,取食高峰在早晨 (8:0 0～ 9:0 0 )和傍晚 (17:0 0～ 18:0 0 ) ,两者各占该时间段全部活动的 5 4 %以上。 (3)藏原羚更喜欢选择蒿草属、火绒草属和棘豆属中数种营养高的植物为食 ,比例高达 80 %以上。 (4) 13个生境因子的聚类和主成分分析表明 :前 4个主成分累积贡献率达到 71% ,能够反映藏原羚主要的取食生境特征 ;影响藏原羚取食生境选择的主要因子分为植物营养度 (特定的植被类型和中等的植被高度 )、干扰度 (隐蔽条件好、人为和动物干扰小 )、水源 (离水源较近和避风性良好 )3个方面。

Feeding Behavior of Tibetan Gazelle in Shiqu County of Sichuan Province during Autumn

Feeding behaviors of Tibetan gazelles (Procapra picticaudata) have been studied with fixing observation and scan sampling in Shiqu County of Sichuan Province from August to October 2003.40 sampling plots (20 m×20 m) were set at least every 100 m apart in order to investigate feeding habitat and diet.Through Kolmogorov-Smirnov test,when the data were of normally distributed parametric tests were used,otherwise nonparametric tests were done.A total of 49 groups (333 individuals) were observed,the largest group observed was 34 individuals,and average size of groups was 6.8 individuals (n=49).Male was inclined to be small group (besides single-individual groups,groups of 2-3 individuals:33.33%,n=9),2 individuals were the most common size of mother-offspring groups (53%,n=15),but very little was observed on the female groups of lesser than 4 individuals.Two feeding peaks of Tibetan gazelle characterized diurnal feeding budgets (one at 8:00-9:00 and another at 17:00-18:00,each of feeding percentages>54%).Higher trophic plants (Kobrecia,Leontopodium and Oxytropis etc.) were the most common diets of Tibetan gazelles,which were over 80% of total recipe.The clustering and principal component analysis of 13 habitat factors indicated that the cumulative contribution of previous four principal components reached 71%,can represent the mainly feeding habitat characteristic of Tibetan gazelles,and the main factors influencing feeding habitat selection of Tibetan gazelles were divided into three types:the vegetation nutrition (with moderate high meadow vegetation),the harassing grade (with better conceal condition and lesser harassment of human beings),and the water resource (with closer to water resource and better lee nature).