Physical processes in clam gardens

PRINCIPAL INVESTIGATOR: Sam Kastner (Western Washington University)

CO-INVESTIGATORS: Marco Hatch (Western Washington University)

Clam gardens are mechanisms constructed by the indigenous people of the Pacific Northwest to improve shellfish access and productivity. These features, consisting of a low wall blocking off the intertidal zone from deeper water, have higher clam yields than the surrounding water, and are culturally important as traditional food sources. Recently, clam garden technologies are being reactivated in the PNW, often in partnership with external researchers. This reactivation is part of a larger Indigenous cultural reawakening as communities heal from past trauma and reassert their rights.

This project will be the first physical process study of the first clam garden built wholly in the modern era to assess the role of these processes in promoting clam growth. The mechanism by which clam gardens promote higher clam growth than surrounding regions is thought to be related to how the clam garden wall alters the circulation of water within the garden. This proposed mechanism may be impacted by a variety of physical processes, including tidal, wind, and wave forcing. Additionally, clam gardens may modify the incoming wave field, which may have important implications for sediment transport and clam garden management. This project will contribute a physical perspective to site selection of future clam gardens.