Nearshore substrate, macrophyte, invertebrate, and clam data collected at field sites pre- and post-installation of a clam garden in the Pacific Northwest (2021-2025)

The Swinomish Indian Tribal Community (SITC) is reviving an ancient mariculture practice by installing the first known present-day clam garden in the United States. Clam gardens are intertidal features modified by coastal Indigenous people (e.g., creating intertidal terraces to alter beach slope and substrate) to enhance clam habitat for optimal shellfish production. Nearshore substrate, macrophyte, invertebrate, and clam data were collected on the clam garden and at a control site pre- and post-installation of a clam garden from 2021-2025 as part of a Before-After-Impact-Control study. Sites were selected to best monitor changes that occur on Reservation tidelands as the clam garden develops.