期刊
AQUATIC BOTANY
卷 76, 期 3, 页码 235-244出版社
ELSEVIER SCIENCE BV
DOI: 10.1016/S0304-3770(03)00051-2
关键词
herbivory; macrophytes; migration; Potamogeton pectinatus; trumpeter swans; waterfowl
We examined spring pond use by migrating trumpeter swans (Cygnus buccinator) to assess their short-term impact on tuber and rhizome density and biomass, and to evaluate the impact of spring foraging on summer macrophyte biomass and species composition. Trumpeter swans in the Canadian subpopulation of the Rocky Mountain population select ponds that are dominated by Potamogeton pectinatus, a macrophyte favoured for its energy-rich tubers and rhizomes. Swans significantly reduced the biomass of tubers and rhizomes present in the study ponds in spring by 24%, but there was no significant impact on overall P. pectinatus shoot density and biomass the summer following herbivory. However, there were significantly fewer small P. pectinatus shoots (<1.0 g DW) in used areas, and other macrophyte species (Myriophyllum exalbescens, P. zosteriformis) were present in areas where foraging had occurred. R pectinatus may compensate for the effects of herbivory, as the number of larger shoots (range 1.0-5.0 g DW) were similar in areas where trumpeter swans had foraged and been excluded. These larger plants likely produce the tubers that will be consumed by trumpeter swans the next spring. Pond areas out of the reach of foraging swans provide a refuge for the tubers and rhizomes, also enabling the persistence of P. pectinatus. (C) 2003 Elsevier Science B.V. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据