长江江豚对八里江江段的利用及其栖息地现状的初步评价  

Habitat use and preliminary evaluation of the habitat status of the Yangtze finless porpoise (Neophocaena phocaenoides asiaeorientalis) in the Balijiang section of the Yangtze River,China

作　　者：魏卓[1] 张先锋[1] 王克雄[1] 赵庆中[1] 匡新安[1] 王小强[1] 王丁[1] 

机构地区：[1]中国科学院水生生物研究所,湖北武汉430072

出　　处：《动物学报》2003年第2期163-170,共8页ACTA ZOOLOGICA SINICA

基　　金：中国科学院创新项目 (KSCX2 1 0 3 ) ;中国科学院生命科学与生物技术青年科学家小组资助(19990 5 1);中国科学院水生生物研究所创新领域前沿项目 (2 2 0 10 3 );武汉晨光计划 (项目号 2 0 0 15 0 0 5 0 5 6)资助~~

摘　　要：通过定点和流动观察的方法 ,作者使用行为指数和栖息地利用指数定量分析了长江江豚 (Neophocaenaphocaenoidesasiaeorientalis)于 1996～ 2 0 0 0年间对八里江江段的利用和选择状况。结果表明 :江豚在八里江江段的行为指数大小顺序为摄食 >抚幼 >玩耍 >休息 ,摄食和抚幼是江豚在八里江江段的优势行为 ;江豚栖息于离岸距离 10 0～ 30 0m的近岸带占 81 8% ,栖息于水深小于 9m的水区占 73 3% ;江豚分布密度随水深增加而逐步递减 (典型的指数分布 ) ;江豚活动水区的流速范围是 0 3～ 1 2m/s ,透明度范围是 0 2～ 0 8m ,江豚在八里江江段对水体流速和透明度没有明显的选择性 ;栖息地利用指数高的断面一般是饵料鱼类聚集、 2～ 4股水流的交汇处。八里江江段的众多异质小生境为江豚提供了充足饵料和繁育抚幼的适宜场所 ;同时八里江江段为江豚提供了庇护、休息和玩耍的足够活动空间。八里江江段成为长江干流适宜江豚活动的最佳栖息地之一 。The only freshwater subspecies of finless porpoise (Neophocaena phocae noides), the Yangtze finless porpoise (N. p. asiaeorientalis) , is only fou nd in the middle and lower reaches of the Yangtze River and the two connected Dongting and Poyang Lakes. Due to deterioration of the habitat quality of the Yangtze Ri ver, the finless porpois population has decreased markedly during the last ten y ears. In order to evaluate the habitat use and preferences of the species, we c arried out stationary and transect observations along the 20 km long Balijiang s e ction of the Yangtze River (29°46′401″E,116°14′602″N) from 1996 to 2000. Th e surveys covered four different seasons, with less effort in summer when the wa ter level was high because of flooding. Two boats were engaged in each transect survey. During transect surveys, both boats synchronously moved up or down along opposite banks of the river and in speeds of between 8-10 km/hr, the distanc e between them ranging from 400 to 800 m depending on the width of the river cha nnel. Stationary observations were conducted from two boats anchored on either s ide of the river. Communication between the boats was maintained using VHF hand held radios. Observers on each boat were responsible for observations in the hal f of the river nearest them. Data recorded included porpoise groups, group sizes , sectors in which they stayed, the time they spent in different sectors, the di stance from shore, behavior and the duration of different behavior. The entire s ection of river was divided into 20, 1000 m long sectors. Porpoise behavior was classified into four categories: feeding, care giving, playing and resting. Env i ronmental and behavioral determinants of the habitat use and preferences of the animals were quantified using two indices, the coefficient of area use (AU) and activity index (AI). By definition, AU=D/T, where D is the time spent by the a n imals in a particular sector, and T is the total observation time on any one day . AI=B/S, where B is the

关 键 词：长江江豚 八里江江段 利用 行为指数 栖息地利用指数 生境分析 

分 类 号：Q958[生物学—动物学]