As discussed in the section on Coastal Development Issues, "the coastal resources of Metchosin are a valuable form of Natural Capital ... The shoreline is an interface between two systems, the terrestrial uplands and the open ocean.....Along our shorelines in Metchosin, we have a variety of unique marine ecosystems: tidal marshes, lagoons, estuaries, bays, eel-grass beds, high speed current channels, underwater caves, vertical underwater cliffs, boulder beaches, sand beaches, and pebble (pocket) beaches. Every metre of coastal intertidal zone also has a characteristic set of organisms, which can be impacted by actions of humans either from the land side or the ocean side.  Larger commercial species of fish often feed or spawn near the shoreline interface, juvenile fish migrate along shorelines, often relying on protective habitat of overhanging vegetation or kelp beds, and the energy flow in the food webs of at least 7 local marine mammal species are directly affected."

The threat from introduced, invasive or alien species:

Already our shorelines have lost much of their native vegetative cover due to the actions of individuals involved in development .Added to this impact is the threat of introduced species displacing the natural vegetation which is so necessary to preserve the ecological integrity of the shoreline ecosystems. A number of references are available on coastal alien species , some of which are linked below. Perhaps the greatest threat may still come from Spartina, so several references are available on that species below. It has not been determined if we may already have outbreaks of one of the three species of Spartina but vigilance is important for the few areas, such as Witty's and Albert Head lagoon, which may be impacted eventual