包头南海子湿地春季北迁大天鹅食性初步分析

2013年2~4月,采用粪便显微组织学分析方法对在包头南海子湿地越冬的大天鹅(Cygnus cygnus)的食性进行了分析。大天鹅的春季食物主要为酸模叶蓼(Polygonum lapathifolium)、玉米(Zea mays)、光果甘草(Glycyrrhiza glabra)和香蒲(Typha amgustifolia)。通过频率转换分析发现,黄河开河之前,首批迁徙到湿地的18只大天鹅,采食酸模叶蓼为主,占食物组成的99.4%;黄河开河之后,迁徙到湿地的120只大天鹅,采食玉米为主,占食物组成的69.7%,光果甘草、香蒲所占比例相对较小,分别为18.3%和11.2%。两个时间段迁徙至南海子湿地的大天鹅,采食植物的种类存在明显差异。大天鹅采食植物的种类与本地的优势植物以及农业生产有着紧密的关系。

Diet Analysis of Migrating Whooper Swan (Cygnus cygnus) on North in the Nanhaizi Wetland of Baotou

Abstract: We studied the diet of Whooper Swan (Cygnus cygnus) from field survey of plants and microhistological analysis of feces. The study was conducted from February to April 2013 in the Nanhaizi Wetland of Baotou. The results showed that: Whooper Swan spring-diet mainly constituted dockleaf knotweed(Polygonum lapathifolium), corn (Zea mays), liquorice (Glycyrrhiza glabra) and common cattail (Typha latifolia). We found a significant difference in the the frequency of each plant consumed in different migratory periods by Whooper Swan. Before the ice of Yellow River is melted, the first eighteen migrating Whooper Swans mainly fed on dockleaf knotweed, accounting for 99.4%. ; After the ice of Yellow River is melted, one hundred and twenty Whooper Swans immigrate again, mainly feeding on corn, accounting for 69.7% of their diet followed by liquorice and common cattail in relatively small proportion, 18.3% and 11.2%, respectively. These results suggest that there is a close relationship between the wetland dominant plants species and agricultural products on the feeding behaviour of Whooper Swans .