Zostera marina is a species of seagrass known by the common names common eelgrass and seawrack. It is an aquatic plant native to marine environments on the coastlines of mostly northern sections of North America and Eurasia. This species is the most wide-ranging marine flowering plant in the Northern Hemisphere. It lives in cooler ocean waters in the North Atlantic and North Pacific, and in the warmer southern parts of its range it dies off during warmer seasons. It grows in the Arctic region and endures several months of ice cover per year. It is the only seagrass known from Iceland. It can be found in bays, lagoons, estuaries, on beaches, and in other coastal habitat. This Zostera grows in muddy and sandy shores only at and below spring tides. This plant is an important member of the coastal ecosystem in many areas because it helps to physically form the habitat and it plays a crucial role for many other species. For example, it provides a sheltered spawning ground for the Pacific herring (Clupea pallasii).