|dc.description.abstract||In an attempt to further an understanding of the biology of suspension feeding among mollusca, ecological and laboratory studies were carried out on three species of clams found in the Kalamazoo River: A. carinata, E. delicatus, and P. coccineum. Four study sites were involved in the ecological studies, from Kalamazoo eastward to Galesburg. Physical measurements obtained revealed water temperatures to range higher at National Gypsum, Sprinkle Road and Comstock Park study sites than at Galesburg. Dissolved oxygen concentrations at all four sites fluctuated unpredictably and presented no discernable pattern. The pH values at all sites tended toward a neutral 7.0. Qualitative analysis of plankton revealed a predominance of diatoms at all sites, particularly Galesburg, with green and blue-green algae in next relative abundance.
0verall plankton counts averaged lowest at Galesburg. Filtration of water samples for suspended material revealed a predominance of organic material at National Gypsum, Sprinkle Road, and Comstock Park, while the inorganic fraction predominated at Galesburg. Laboratory filtration studies of the three bivalve species cited in Neutral Red suspensions revealed filtration rate per gram of body weight to decrease with increase in body size. Of the three species, the ecological and laboratory data suggest that P. coccineum demonstrates an aversion for concentrations of particulate matter wherein the organic fraction predominates. Data also suggest that P. coccineum prefers lower temperature ranges than both A. carinata and E. delicatus.||en_US