Eelgrass is often mistaken for a seaweed, but it is actually a flowering aquatic plant which has evolved to colonize the marine environment. The combination of fresh and salt water, sediment, light and organisms interact to form a unique and biodiverse system. It is estimated that over 80 percent of commercial fish and shellfish species depend on eelgrass habitat at some point in their lifecycle. On the South Coast the Fraser Estuary, Robert's Bank, Sturgeon Bank and Boundary Bay support one of the most extensive and contiguous eelgrass communities globally. Industrial, residential and recreational development and activities continue to put eelgrass communities under pressure and have resulted in the loss of a number of historic eelgrass communities, especially in places like Vancouver Harbour. Eelgrass beds also assist in coastal protection by supplying a physical barrier and reducing coastline erosion. Restoration of eelgrass communities is underway in Burrard Inlet and Howe Sound.