Uptake and Elimination of Coliform Bacteria by Four Marine Bivalve Mollusks

Abstract

Bivalve filter feeding mollusks remove suspended bacteria from the ambient water and either sediment them with the pseudofaeces, or ingest and digest them. On the basis of bacterial contamination of water and known pumping rate, accumulations usually exceed expected levels by an order of magnitude. This does not reflect high uptake efficiency of the bivalve, but is a function of the digestive process separating bacterial clusters, thereby increasing inoculative loci both for multiple tube estimates and plate counts. Uptake rates are species specific and temperature dependent and show little correlation with the ambient bacterial loading. Elimination is also species specific and variable.