The Swinomish Fisheries Department has been monitoring shellfish populations on Reservation beaches for over a decade, yet to date there have been limited efforts to determine the factors influencing year to year population variability. Populations of some economically and culturally-important hardshell clam species (butter clams, Saxidomus gigantea) have remained relatively stable over the survey period while others (most notably native littleneck clams, Leukoma staminea) have experienced dramatic declines. Nearshore environments along the Swinomish Reservation have experienced subtle changes over the years in terms of beach substrate composition (from local and landscape-scale land use changes), timing and magnitude of freshwater events (including river discharge and precipitation), and most recently an increase in the number of significant storm events. Through this proposal they will build upon existing shellfish restoration and research programs at Swinomish through the advancement of shellfish habitat and population dynamics research. Specifically, they will examine the hydrodynamics that drive larval transport and post-settlement survival of shellfish species and target future shellfish restoration based on survey results.