The MARINe (Multi-Agency Rocky Intertidal Network) Biodiversity Surveys provide detailed information about biodiversity and community structure at sites ranging from Southeast Alaska to Mexico. These surveys were designed to measure diversity and abundance of algae and invertebrates found within rocky intertidal communities on the western coast of temperate North America. Through the Sentinels Alliance program, we plan to conduct MARINe surveys in several locations throughout the Salish Sea including Quadra Island, West Vancouver, and Hornby Island. An additional 4 sites were established in 2025 near Port Renfrew, Victoria, the Sunshine Coast, and on Mayne Island and all sites will be surveyed every year. The goals of the project are to determine the diversity and site-wide abundance of intertidal algae and invertebrate species, reveal long-term influences such as climate change and coastal development on intertidal communities and individual species, examine patterns of biogeography with a particular emphasis on locations where there may be large changes in species composition and diversity.