Feedback between zebra mussel selective feeding and algal composition affects mussel condition: did the regime changer pay a price for its success?

Autor: James R. Liebig, Henry A. Vanderploeg, Thomas H. Johengen
Rok vydání: 2009
Předmět:
Zdroj: Freshwater Biology. 54:47-63
ISSN: 1365-2427
0046-5070
Popis: Summary 1. We investigated the role of algal composition on pumping, clearance, assimilation, pseudofaeces and faeces production, feeding time budgets, and condition of zebra mussels from spring to autumn at two sites in Saginaw Bay (Lake Huron) and one site in western Lake Erie. Size-fractioned chlorophyll was used to distinguish between feeding on small ( 53 μm) size fractions, and mussel feeding behaviour was quantified by video observations. 2. Mussel pumping, clearance and assimilation rates varied among sites, particularly during summer, when phytoplankton composition varied considerably among sites. Lowest values were seen at the inner-bay site of Saginaw Bay, low to moderate values at the outer-bay site of Saginaw Bay, and high values at the Lake Erie site. Clearance, pumping and assimilation rates were all highly positively correlated (R2 = 0.76) with per cent contribution of flagellates to total algal biomass and negatively correlated with per cent of Microcystis aeruginosa (R2 = 0.63). The negative effects on pumping rate (as determined by clearance rate on the 53 μm fraction, could be mitigated by the presence of flagellates in the
Databáze: OpenAIRE
Externí odkaz: