The North Coast has 16 major estuaries that support a wide diversity of plant and animal life, including salmon and other commercially important species. The focus of this project is to describe and evaluate the ecological status of representative and under-studied estuaries in the region by surveying plants, invertebrates and fishes in tidal mudflats and eelgrass beds of four estuaries – three within MPAs (Humboldt Bay, Big River and Ten Mile River) and the Mad River Estuary. Field surveys will be conducted multiple times a year for two years to better document seasonal and interannual variability in species abundances and diversity, as well as changes in the sizes of focal species, such as bivalves, eelgrass, and black rockfish, among others. Estuarine ecosystems are largely driven by a complex set of interacting physical variables, including freshwater flows, seasonal closures of lagoon mouths and ocean water properties related to winds and upwelling. Information about these “abiotic” variables will be distilled to describe the “contextual conditions” in each estuary. During the analysis phase of their project, scientists will identify baseline and contextual metrics that might allow for future evaluation of MPA performance. This project is a collaboration among academic scientists, North Coast tribes, and ecological consultants.