| one publication added to basket [59060] | Compensatory growth responses of Potamogeton pectinatus to foraging by migrating trumpeter swans in spring stop over areas
Lamontagne, J.M.; Jackson, L.J.; Barclay, R.M.R. (2003). Compensatory growth responses of Potamogeton pectinatus to foraging by migrating trumpeter swans in spring stop over areas. Aquat. Bot. 76(3): 235-244. http://dx.doi.org/10.1016/s0304-3770(03)00051-2
In: Aquatic Botany. Elsevier Science: Tokyo; Oxford; New York; London; Amsterdam. ISSN 0304-3770; e-ISSN 1879-1522, more
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| Keywords |
Aquatic organisms > Heterotrophic organisms > Herbivores
Behaviour > Feeding behaviour > Grazing
Environmental factors > Biotic factors
Food preferences
Interspecific relationships
Population characteristics > Biomass
Population functions > Growth
Cygnus buccinator Richardson, 1832 [WoRMS]; Potamogeton pectinatus L. [WoRMS]
Canada, Alberta, Calgary
Fresh water |
| Author keywords |
herbivory; macrophytes; migration; Potamogeton pectinatus; trumpeterswans; waterfowl |
| Authors | | Top |
- Lamontagne, J.M.
- Jackson, L.J.
- Barclay, R.M.R.
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| Abstract |
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. P. 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. |
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