Howell et al. (1996) reported that zebra mussels colonized soft sediments in an area where eastern Lake Erie flows into the Niagara River and that this colonization had an affect on sediment quality. The sediments became more silty, increased in organic carbon levels, and polycyclic aromatic hydrocarbon compounds were found to be at higher concentrations. The benthic community also changed as a result of zebra mussel colonization on soft sediments.
On sandy sediments, zebra mussel colonies form when individual mussels settle on native clams, snails, stones, and shell fragments. Subsequently, additional mussels settle on previously settled mussels, and druses are formed. As these druses continue to attract further settlement activity, the sandy substrate is changed into a mosaic pattern of colonized areas, thus altering the benthic environment.
Berkman et al. (1998) examined Dreissena assemblages on soft substrates in western Lake Erie where it was demonstrated that mussels can propagate their byssal threads over grains smaller than 1.0 mm. The mussel is able to conglomerate these small particles and form suitable settlement material.