In subarctic and Arctic waters, coastal areas are often dominated by habitat-forming macrophytes (kelp or seagrass). These underwater beds and forests are an important source of primary productivity, provides habitat for a wide range of organisms and act as both nursery grounds and critical foraging habitat for many harvested species. There is growing awareness that these blue forests represent natural climate solutions through their role as carbon sinks, nutrient filters and focal points for biodiversity, as well as an untapped source of sustainable materials. Marine macrophytes, particularly macroalgae, are themselves harvested and provide both cultural and economic benefits for maritime communities. Given the vast extent of these coastlines in northern regions, it is critical to understand their current distribution and the functioning of their associated communities, to explore the possibilities for sustainable harvest and exploitation, and to address possible future changes in these critical habitats.

Kathleen McGregor, Karen Filbee-Dexter, Amanda Savoie