This project brings together researchers, community members, Hunters and Trappers Organizations, and regional organizations to observe the ocean and study the ecosystems of contrasting coastal marine regions ofHudson Bay and James Bay. Four focal areas have emerged: (1)the northwest coast (near Coral Harbour, Naujaat, and Chesterfield Inlet), (2) the southwest coast (Nelson River area), (3) the southeast coast (near Sanikiluaq, Chisasibi, Kuujjuarapik, Umiujaq and Inukjuak), and (4) offshore James Bay. Within this broad geographic domain, the research aims to collect new observations during winter, spring, and summer with emphasis on a community‐based sampling approach. Our goal is to identify the factors that influence nutrient availability, ecosystem productivity and the export of organic carbon in each coastal domain, and compare the coastal regions, which contrast strongly in sea‐ice formation and river inflow. The coastal domain extends throughout Canada’s Arctic marine waters and includes ecological hotspots that are critically important as marine mammal and seabird habitat. It is also the domain along which Cree and Inuit live, hunt and travel.